I have to say that this is one of the best ideas I have seen on RUclips. Of course condensation will form in the rad, but being cast iron and the exhaust low, it will drip out the bottom. Those heaters burn so efficiently that you won't have to worry about soot collecting in the rad. To test for this possibility, when it's new, record the temperature drop from top of rad to the bottom. After running it for months, or years, keep testing the temperature difference. If soot is forming on the inside of the rad, the temperature difference will become less. The exhaust temperature, at the floor will increase. The soot will act as an insulation. I can't see that happening though because of the burn efficiency. I only thing I would do differently is a more positive, sealed connection between the iron pipe and the heaters' flex line. Easy fix. As for the haters in the comment section, these people are shocking ignorant to basic science. You can tell they have done nothing in life. Nice job. It has given me some ideas.👍
I totally agree with @daveunderwood6498. The only comment I would make, and I'm being picky , are the 90 degree elbows but they do save space and that's the only a minor restriction .
Thank you very much for this nice comment. It's very motivating to read something like that and especially to see that people actually think about it. You're certainly right about the connection, although that causes more problems on the heater side than on the radiator side. The heaters are made so cheaply that a professional connection of both elements is a major challenge. Essentially and generally necessary. There is no point in connecting to the flex line with a hard-soldered flange if a stupid pipe clamp is supposed to seal the system at the other end. I chose the aluminum tape as a temporary solution as I'm still experimenting with this system, and I have to say after two years it's still tight and in very good condition. I haven't poisoned myself with CO yet and I don't need rubber boots for the condensate that forms as my other Diesel Heater vodeos prove LOL
Ive been doing this for 3 years with an old steam radiator, have many videos about it here on YT. It works fantastic, no condensation problems as the armchair quarterbacks and internet experts always bring up. I have over 1000 hours of use with no issues, you want the exhaust from the heater to go in on the bottom of the radiator, exhaust out the top port which allows convection and hot air rising to remove condensation. The large internal volume of the steam radiator prevents backpressure so the combustion fan doesnt work too hard like it would with a long exhaust run, the hot air convection from the heater exhaust coming in from the bottom and exiting out the top (in my system) propels the exhaust out without putting undue work on the heaters fan, it also allows the stored heat in the thermal mass to continue to remove moisture even when the heater is off.
Interesting - I have a heat exchanger to rig up to my Webasto exhaust that will share a coolant loop with the radiator circuit. Trying to get the pipe as short as possible before entering a 3inch full exhaust system - for the same reasons as you've explained.
@dancarter482 That's awesome, I remember seeing a commercially produced heat exchanger unit specifically made for diesel heaters on *David McLuckie* YT channel, as well as DIY versions using EGR heat exchangers or coils of copper etcetera...very interesting indeed. The unit that comes to mind was this fella who built the most amazing converted army truck RV-he uses both a woodstove and a diesel heater to warm his hot water tank as well as the coolant loop for the diesel engine, its quite a slick setup: ruclips.net/video/y8vKhf1p1Lg/видео.htmlsi=mfY0eX63LbbP1oRP
How does condensation not end up sitting in bottom of radiator? Or are you saying the heat vaporizes it and pushes it out with the exhaust? Seems like the down draft shown here would simply allow the moisture that's created to flow out with the exhaust at the bottom. Or are you saying the condensation that is created simply does not create any problems?
Many people who watch this video are of the opinion in their comments that heat rises upwards, which is physically correct, but cold falls downwards, which also creates a downward suction in the radiator. That's why the entrance is always at the top and the cold that occurs when it cools down doesn't have to fight against the rising heat. On a car radiator the hot water inlet is at the top and on a household radiator the inlet is always at the top to achieve optimal heat exchange. It is also correct that you should not make the exhaust pipe too long, otherwise the resulting flow resistance will be too high, but given the flow cross section and the length of the components installed here, this shouldn't really have an impact. Since the difference in height between the exhaust gas outlet and the radiator inlet is approximately 45 cm or 18", there is virtually no back pressure. An exhaust silencer would generate more back pressure. And with an exhaust gas temperature of over 150 degrees Celsius, there is guaranteed to be no condensation in the pipe On the contrary, it will evaporate and condense again in the radiator where this condensate can then drain downwards. It is absolutely likely that deposits will accumulate somewhere in the system, but the solution to this is regular maintenance and cleaning. Every boiler, fireplace and chimney must be cleaned regularly, even Chinese diesel heaters are not maintenance-free forever.
I like your design and am planning something similar...after seeing a bunch of Tubbers designs I think an oil or car radiator would be most efficient but I worry about corrosion. My idea is to run the exhaust thru a honda or toyota radiator and have the fan cycled with a fan relay in the heater, but i wonder how long it will last w/o antifreeze. That one your using is designed to run water through isn't it? an oil radiator might not last with water going through it either.
@@dh2032 I"ve seen some fellers on the Tube do that but it looks like a hassle... leaning towards getting salvage yard rad/fan and hanging a CO detector on it , with frequent inspections.
People think that but it's simpler than the rise and fall. Hot always moved towards cold. The thermodynamics of thermal energy is straight forward with that
For this to work, long term, you need to have the exhaust pipe from the diesel heater well above the radiator, so the condensation will flow down and out, through the radiator, as vapor. The way you have it set up, currently, the heater will eventually clog.
I was going to write the same remark. All the condensation will stay in the exhaustpipe the way it was set up. Maybe fit the exhaust to the bottom and do the pipe on top through the floor?
The temperature in the flex pipe going from the heater upwards to the radiator is so high that you don't get condensation there. Maybe a few drops at startup but it evaporates as soon as it gets up to working temp. I have the flex pipe going upwards in my boat and have had no issues in the five years I've used it.
WRONG ....There is no condensation once the heater is up to temp (a couple mins) and any condensation that collects in the radiator will drain out. By your logic every vertical exhaust on every diesel engine ever would plug up.
Just to agree with the others, you can't have an exhaust pipe going up the way. It'll just fill up with vapour and condensation It must constantly go downhill. for this to work long term. If you look at the silencer. even that has a hole in the bottom to get rid of vapour for that very reason. You will need to raise the heater. or to have a Lower. Radiator. In principle, it should work OK then. The other option. is to use. a part from a car. I think they call it EcG. It allows you to pass the exhaust through. a water chamber. and then send the water through the radiator. That could work on your existing radiator so long as you have the exhaust at floor level. as it enters its heat exchanger. You would just need a small expansion chain. literally tiny. nothing bigger. than the size. on a car. Radiator top up. and it won't even need to be under a pressure. So long as it's at the right height.
On a Russian site a man did this and did a lot of calculations based on the actual heat values - he concluded the heater itself produced just over 4kw on high and his radiator added a further 1.5 kw making a total of a little over 5.5kw - in another of his posts, he concluded that the 5 and 8kw heaters were in most cases the same!
Good use of old cast iron radiator. One Major Flaw with exhaust fumes exiting building. Even though your building barely sits above concrete pad , carbon monoxide fumes with hang next to floor and will leach back up through your high temp wool, as well as between seams between floor sheeting. You should have extended beyond building a foot at least and away left or right of window. Remember CM KILLS.
Diesels don’t make much CM, that being said you’ll still die, you’ll just die before any monitor will warn you. However that’s not even my biggest issue, the intake for the heater itself is INSIDE, it’s like hooking the intake from your car to the cabin. That should speak for itself
I have my heater exhaust hooked up to a 40 plate flat plate heat exchanger connected to my boats hot water tank. The heater heats my boat, the exhaust heats the water. It works amazing. It heats the 9 gallon tank from 70F to 130F in under 90 minutes. As long as the water is above 70 I I’ve no issues with condensation or soot.
I should mention the water thermo siphons through the exchanger, meaning the water is constantly at 180 approximately. I also remove the exchanger often to make sure it’s clean and remove any condensation.
I love your idea. Thanks for sharing. I am looking for a unit to heat my sailboat and then in winter, transfer the setup to my truck and also pre warm the engine, and you just solved the problem. I am a heating tech and have access to many different stainless steel heat exchangers. You made it all come together, buddy. Thanks
Great idea, the only downside is the condensation created by combustion which is going to collect at the exit of the exhaust gases because you have it running uphill. But even if it was plumbed differently, it would be trapping condensation throughout. But if it stops functioning, it’s because that bottom exiting section is too full of water
How people think the pipe can collect water with a tepereatur from over 220 degece Celsius the pipe is still nice and clean after 2 years no problem with it.
I would have figured someone would have caught on to all these comments about diesel combustion creating condensation. Now if it was gasoline then yeah it will have to be drained
Did the same thing, works fine, as long as you reduce the amount of fuel, with the default settings, the heater is running rich because off, the reduced exhaust air flow, if you keep on running it with default settings, soot will build up and clog your heater.
Make sure you can drain the radiator because the exhaust is humid and going through the rad it will condensate the water in it, unless the output is right at the bottom. . Place a few computer fans blowing against the rad to dissipate some of that heat into the room. Also you should be getting fresh air from outside because you are using the air in the shop and exhaust is pushing that air out so to compensate for the air going out, it will draft into the shed from all the cracks
I ran exhaust in to the bottom side of my cheap wood stove, it captures all the exhaust heat and the fumes go out the chimney pipe. I can still use the wood stove when needed.
Brilliant, this is way better than what I had planned because that cast iron rad will also act as a thermal mass, which will continue to keep things warm a little longer, even after the heater shuts off.
Convert the radiator to a simple heat exchanger.. Fabricate a pipe that passes through the radiator from top section, looping to the lower and out as you have done with the existing exhaust path. That then allows the radiator to be filled 95% with water [for expansion, don't seal it!], giving more mass to capture the heat. If you've a pump that can handle near boiling water temps you can then add more radiators to the system.
Very interesting video. And a real bonus for us viewers. No annoying, irritating, loud background music. except for a little at the end of the video. 👍
When I first installed my diesel heater in my caravan, I connected the exhaust directly to a 3 meter length and steel 1.5" water pipe, then out through the floor, the water pipe 3" above the floor is 190° and is awesome for keeping that heat inside instead of heating up the atmosphere lol, I could have made it go around the room further.
Great idea! Since the unit and the exhaust path is inside, please make sure to have a small space carbon monoxide detector (they are made for inside of small spaces like airplanes and semi trucks and are more sensitive) inside the shop/shed. I agree with the comment that the outside exhaust outlet should be extended past the building side (instead of just down under the shed floor - ideally up past the roof peak). Also, keep an eye on the temp of the pipe going through the floor to ensure the mineral wool is taking any residual heat before it reaches the flooring wood (thinking of a chimney wall/ceiling collar and how it separates the combustible surfaces from the heat of the exhaust pipe). Nicely done!
@@jacekolejniczak8726 Anywhere you have a union or join in a combustion exhaust run indoors, you want a CO detector. You also don't want to exhaust any combustion equipment simply down through the floor unless it continues outward well past the building. So he sounds a lot smarter than you do, especially since he's given good advice and all you've done is make a dick of yourself without providing any input or backing up your comment at all.
Many folk have done similar things with these heaters some much safer than others, but i don't remember seeing a vid which addresses the potential corrosion issue.
Simply Genius!!! Works perfectly as these diesel heaters use a forced burn. Radiator is a steam radiator so any condensate will only happen in the lower section as water vapor is naturally drawn to cooler surfaces! Any water that collects in the bottom will eventually be blown out due to the forced airflow. ❤️💯❤️
Yes as the other comment say you should definitely have your heater exhaust higher than the radiator. The exhaust should never go uphill it will trap condensation and damage the heater long-term. In principle it's a very good idea but not executed correctly exhaust should go in the top and out the bottom of the radiator on the opposite side.
if anyone wants a cheap super simple way to extract heat from the exhaust, just buy a pack of scotch bright stainless steel scrubbers. You can expand them from the middle and slip them onto the exhaust pipe. They have a ton of surface area and conduct heat from the pipe really well. they work pretty well already by passive heating, but you can add a fan to help a little. You can buy a 16 pack for $10. Thats all you need.
Careful about back pressure. If you can, expand the exhaust pipe before you do this because if you plug the exhaust, the burner blower will start to force air out the sides of the exhaust instead of straight out
I'm so glad you did this. I was planning the same set-up with a heater I just purchased and have a radiator already. Thank you for proving concept. Much love
better go for a stainless steel pipe with slightly larger inner diameter as your exhaust hose and root the exhaust gas through that. I use a 2.6m long pipe that simply goes through the room and then exits with a slight downward slope. The pipe then just goes through the wall. The end of the pipe is at around 30°C so i get the same efficiency with much less effort and dont even have corrosion problems. I put a small bucked that collects the condensate under the exit of the pipe outside of the building so the sulfur does not go into the environment. The whole thing cost me around 30 bucks.
Ive had mine running in my garage for five years now, I think I'll try this when I reorganize later this year. the other benefit would be to hold the heat when the heater turns off, that much iron should remain hot for a while.
One more thing to consider - taking outside air trough recuperator. Now you are creating lower pressure inside room and outside cold air is leaking through cracks
Thank you for making this. I’ve always thought the exhaust made so much waste heat in diesel heaters. Rv heaters etc. Awesome to see you come up with a way to harvest it.
Nice idea to recoup the heat lost by the exhaust, but I would have turned the unit around to have the heat vent also blowing through the radiator. This would have a two fold benefit: 1. it would help to heat up the thermal mass of the cast iron radiator quicker, and 2. Once up to operating temperature the hot air passing through the fins of the now heated radiator would distribute the heat from the radiator better. On a side note, I would definitely add a 90° elbow to that exhaust under the shop and run it out from the perimeter of the shop (the rockwool may help where you drilled the hole, but there may be a couple seams on the underside to let fumes back up into the shop).
Not really. Heat inside is what matters. If you transfer heat to other objects changes nothing .....unless it increase heat radiated to the outside, which it might. Capturing exhaust heat helps but dumping heat into a cast iron heat exchanger instead of aluminum is less efficient but better than just dumping it.
something else to consider is the intake air to the combustion chamber, take it from outside. Else you consume the hot air from inside the building and cold air will leak in from outside.😇
Problem you are going to have with this setup is condensation in the radiator. The condensate is very acidic so it will rust that radiator though in no time. You can get round that however by using a stainless steel radiator. Also you need to have the exhaust coming out of the heater going down into the radiator so there is no chance of condensate collecting in the tube. I have a similar setup myself except I packed the exhaust radiator in sand as thermal storage so I can turn off the heater and get several hours of residual heat.
It is 25-35% more efficient, not 200%, but I can understand your excitement 😉. The exhaust of a diesel heater wastes 0.1 to 0.7kW of energy depending on the heat setting of the heater. The 5kW heater is actually a 3kW machine. You can pass the exhaust through a bucket of water and you get hot water.
I was thinking the same. Im thinking about building a CH system with water ( as I already have with nat. gas ) and exactly as you said, run the exhaust trough the water for extra heating efficiency.
@examplerkey there all rated at 5kw but they like to lie and say 8kw. pretty normal for anything from China and even then there really only about 4kw. But there is a newer model that is about 6kw rated at 8kw and has a bigger burn chamber with a 3.5" outlet but only a few company's are selling them. There is also a smaller 2kw model available
Great idea! I would have the exhaust coming into the bottom of the radiator as this would allow the moisture from the engine to rise out the top as steam.
thanks, that's a great idea, and what makes it even better is I have a small cast iron radiator sitting unused in the basement. I am quite satisfied with my little diesel heater, but I have been thinking of a way to recover the heat lost through the exhaust because my shop is quite a bit too large for the poor heater (20ftx30ft) and I live in a cold climate.
A meter of standard exhaust, always going down or sloped downwards, with a small fan blowing on it will yield room temp exhaust at the end with no carbon. Also have the intake on the inside air to limot the effect of having to heat the air too.
I made a recouperator for mine with a 3m coiled section of the same exhaust tubing. It's got a riser section coming out of the heater and coils downward to the outlet. No fan, purely convective. Exhaust temps at the recouperator outlet are around 40c and just as you're experiencing, no soot. I was surprised as I was expecting at least some soot. I get lots of condensate as evidenced by the large puddles the thing makes, but I'll take a puddle with the extra BTUs. Its a garage I'm heating. Puddles there won't hurt anything.
I'd have used an EGR cooler to transfer the waste heat to water. If you don't need hot water, you could use a car oil cooler with a small fan to extract the waste heat into the air. Same principle as your cast iron rad, but much more compact. I'm not sure how you calculate a 200% increase in efficiency. You've not made any energy / volume calculations. Also, I'd advise that you put a 14.8 volt 10 amp power supply on that battery to keep it from cycling. That way, you'll never have to worry about it going flat, and you'll have heat for hours if you lose grid power.
Test done on an Artic blog established that a claimed 5kw "Chinese" diesel heater gave 31/4 KW on full and a further 11/4 KW could be recuperated from the exhaust by passing it through a large radiator - a 38% improvement not 200%
A Russian post did some tests on this type of heater and found that the 5kw produces just over 3kw and adding a radiator on the exhaust added not quite 11/4 KW - he based his results on fuel used calorific value
Good to see someone else in NS doing stuff like this besides me. LOL Been using these CDH for a while. You will have issues with carbon build up eventually and condensation building up with the exhaust angled upward like that. Everything on the exhaust should be on a downward slope to prevent condensation build up and giving it a path to drain. Also move the combustion air intake outside of the space, when it does foul up it and it will at some point it will dump all the exhaust gases back through the intake manifold into your room because the intake and exhaust share the same combustion space. CO monitors are a must. Stay safe and good luck.
Yes the combustion air intake should always be outside. When inside they will pull cold air in from the outside through every crack and crevice it can because of negative pressure. I have seen the result first hand from my own mistakes and experiments over time.
That's an ingenious idea! I've got another idea for you that might also increase efficiency. Make a shroud for the back of the radiator and then hook the heated air hose to that so the already heated air is used to make a forced air setup for the radiator as well
Indeed...I have the same system..my heater is placed outside in a plastic nice box and the exhaust pipe is coming in at the top of the radiator and goes out at the bottem. My heater is at the highest point and the exhaust pipe is running down so water can run out at the bottom of the radiator.
If the temperature is over 190 Celius, wouldn't any moisture be vapourised? Once cars reach normal temperature, you don't see any moisture coming out of the exhaust pipe.
Great job, BUT.... the exhaust outlet is designed to run at a typical specific 45 degrees.. there abouts downward . This downward slope from outlet through exhaust pipe to tip into muffler is needed to allow exhaust pipe to drain moisture to weep hole in muffler, note muffler needs to have it's weep hole facing down to drain... moisture from system. You directed your exhaust in the opposite direction.. this will surely trap moisture in your line and your radiator system..
White PTFE tape is meant for non-corrosive liquid and gasses, the Blue PTFE os for corrosive gases and liquids. I'd take it apart and use the Blue before the White tape degrades and leaks gasses into your space... Also, heat rises, so heating should be at floor level, whereas cold sinks, thus AC should be at ceiling level. ☺☺
There might be even better way. Diesel water heater. Plum it into one more cast iron radiator and use aquarium pump to circulate the water mix. Two radiators would stay warm even after burn cycle. Especially one filled with hot water. BTW exhaust hose should never go up according to manufacturer.
I think you'd be able to increase the efficiency by using outside air for the combustion air intake instead of indoor air. You're creating a negative pressure space, drawing cold in inside the building. Outside air will combust the fuel just as well and wont create a negative pressure. In the end you'll use much less fuel to heat the indoor air.
Should feed exhaust into bottom of the rad and out on the other side bottom. Heat rises. Rad would be heated way more evenly. Plug the top fitting. And no galvanized pipe in exhaust, too hot, zinc fumes released over time. Other than that - well done.
Great video. The one thing that concerns me is Carbon Monoxide collecting under the shed and creeping back in. Did you put an elbow underneath with another pipe to take it away from the building?
I’m also concerned about the build up of soot as the exhaust condenses on the interior walls of the radiator. Also he could put a fan directed at the radiator to pull more heat from it.
If your exhaust temp is lower than 140° it will condensate which is acidic which WILL rust that radiator out faster than you think. If the rad was stainless you wouldn’t have that problem. This is exactly the reason high efficient furnaces / boilers/ hot water heaters cannot use regular tin exhaust vents, they have to be able to resist the acid which is present in consensate. Master plumber/gasfitter 25yrs
I have one of those heaters. Why does the top of the radiator show 45°c & the bottom -4•5°c? I know heat rises, but I would have expected around 20°c at the bottom. Maybe it's because the radiator is cast iron & it takes far more energy to heat it up thoroughly. I know my friend uses a slimline pressed steel radiator & it heats up fine, albeit the bottom only heats up to half of the top temperature. Here is just a tip. He found that by having the air intake in his workshop, the heater wasn't working to its absolut potential, so, he put the air intake outside & found it worked much better therefore producing more heat. Anyhow, thanks for sharing. 👍
Produces the same heat with outside or inside air. But the inside air that it sucks to burn and then goes out the exhaust to the outside creates a very slight vacuum in the room, and then the cold outside air seeps in from every possiible crack and hole, countering some of the heating. Using outside air prevents a vacuum from forming since you are taking outside air for combustion and exhausting it outside, maintaining a pressure balance.
You could also build a sand battery and run the exhaust through that to prvide a thermal mass that will carry on pushing out heat after the heater is turned off.
So many 90 turns on exhast before radiator. Build up in radiator. Aluminum foil. Make your exhaust straight line between radiator and bunk heater, add slow big fan on your radiator.
If you want to improve efficiency, I'd start with an intake duct and intake-exhaust heat exchanger: every cubic meter of ambient air used for combustion is a cubic meter of cold outside air that gets drawn inside and needs to get heated back up, much like single-hose portable ACs. If you dump all of the exhaust heat into combustion air drawn from outdoors, you eliminate the draft and the warmer combustion air also helps the diesel vaporize faster so it can burn cleaner. That is how high-efficiency boilers achieve their ~95% figures, nearly all of the exhaust heat gets absorbed by replacement air. You can also use some of the exhaust heat to pre-heat the diesel by ~100C to help vaporization for a cleaner burn too. When liquid or solid fuel hits the flame, the flame has to put in the remainder of specific heat to get fuel to the boiling point, latent heat of vaporization to turn it into vapor and activation energy to ignite it. Pre-heating the diesel saves the flame from having to do most of the boiling part the work in what little time the fuel spends inside the combustion chamber. You still get the scavenged exhaust energy back in the form of a slightly hotter and cleaner burn since the flame has more net energy left in its exhaust for heat exchangers. BTW, don't use an IR thermometer on shiny metals, readings can be waaaaaay off. Especially if there are other strong IR sources nearby such as the heater's direct exhaust pipe at ~180C: you may be getting a temperature reading from reflected IR instead of whatever you are pointing at.
The first broblem I see is the heater is not above the radiator to drip away moisture remember how they are fitted in RVs the exhaust always runs down to drain and with that size of rad you are gathering a lot of obnoxious gases.
Exactly! It's not gonna work for long, so this tutorial is misleading. I once installed longer exhaust pipe, and it was only slightly bent upwards in the middle and it was enough for the unit to stop working. When i detached the exhaust and bend it to the ground lots of moisture came out
well thank you for this fantastic plan. I started looking for a radiator right away, I found a old ornate one that came out of a house on york Street in Halifax. We're takin this rad to the camp! great idea! thanks again
Seems very good heat recovery. It's good that you exit straight down thru the floor so condensation goes out with the exhaust. One thing I would love to see done is to preheat the combustion intake air from some sort of heat exchanger with the exhaust. I'm thinking it would make the fuel burn better but not having one (yet) to experiment with I do not know. Enjoy your warm shop!
Only 3things i would change is (1) have the unit higher so the exhaust is always flowing down in case of condensation, and (2) I would do a better job of sealing off the exhaust through the floor, maybe spray foam or calk, and (3) hook up a trickle charger to the battery.
Now have the blowing end of the heater blowing across the radiator to pick up that heat and also move the air inlet to the first part of the radiator at the hottest part so it is picking up the hot air will make the heated air hotter. If you understand what I am saying. Sort of a loop system making it help itself heat better.
From your friendly local heating guy (TSSA licensed ) Please dont do this.... That cast iron radiator is not meant to control products of combustion. Teflon tape is not heat rated.... That exhaust through the floor will definitely seep back into the building, and, will create a ton of moisture under the floor causing wood rott. The concept is absolutely correct, but this is a big carbon monoxide risk.
Can you explain more? What's wrong with having a radiator on the exhaust end? If there are no leaks and he has a detector if leaks happen later? Why can't he exhaust through the floor and elbow out past the side of the building?
@@remyllebeau77 The exhaust can run through the floor, in vehicles (where these are intended to be installed) the exhaust always goes through the floor, unless you have one of these chinese things. But that hole in the floor has to be sealed to prevent poisonous gasses from entering the building. Stuffing rockwool that rodents will remove does not count as sealing the whole lol. Yes, you can have a CO2 detector, but if you how important is your life? I wouldn't install something that will leak, and rely on a detector to wake me up. Then there's the issue of corrosion inside of the radiator, carbon build up, and all kinds of things that this dude is clueless about.
You need to add a drain valve to get rid of condensate building up in your radiator. Alternatively, use a more modern type (sheet metal) and tilt it so the condensate can exit via the exhaust.
Nice idea - I may give that a shot. I think you definitely need some kind of drain for condensation, though. You are dropping the air temp down to well below condensation temp by the time it exits the radiator, so I am betting you will soon have the bottom of the radiator full of fairly acidic condensate, which will likely do some significant damage to the internals of the radiator in the short term if you don't have a way to drain it. The cast iron would last a century if you ran clean water through it, but letting acidic water sit in the bottom will do significant harm to it. Even if the radiator cast iron holds out, you will eventually be dumping that acidic water out onto your cement slab. If you don't want to put in a drain, I would think about pouring in some thin epoxy like the stuff mean to repair pinholes in gas tanks, and flipping the radiator around until it is coated inside evenly. The epoxy may give you some extra time before the radiator bottom perforates. Thanks for the great idea!
Interesting idea, I just ordered mine. Ill be running exhaust through a muffler i bought for my chevelle. It arrived with a dent so they sent me a second one free. Sol i can use the large surface to exchange the exhaust heat....
This is a really bad idea that could be fatal from CO poisoning. I won't nitpick your math, but I will warn you of letting the exhaust temperature fall below 212F inside of a metal pipe. Sulphur is a byproduct of burning petroleum based fuels, and if will react with surrounding gasses and forms sulfuric acid that will condense on your metal pipes and you will start getting holes in your radiator. Guess what other gas is formed when you burn hydrocarbon based fuels?
@@SuperDirk1965 Unfortunately, we might be taking weeks to months with heavy usage... especially if it all completely condenses on the walls of the radiator.
@@joelhacker8767 Indeed, check for damage to the radiator in ten years. It's a cast iron radiator. Do you know how thick those walls are. The exhaust pipe going into the radiator will be long gone before that radiator springs a hole. Even the heater may be worn out by then.
I'm going to use some flexible dryer duct and put it around an extended exhaust (I already have both) and run a small DC fan at the bottom of the heater where the exhaust starts and split it off before it goes outside. I should be able to nearly double my heat output from 1 heater depending on the CFM of the fan.
I think the idea is brilliant BUT I feel you're Heater unit must be located higher to allow the condensation to flow down & out of the radiator outside, The way it is at the moment your creating a U loop with no way for the condensation to run away .
If the exhaust temp is above the boiling point of water, no condensation can occur. However, he will get condensation inside the radiator, and it will freeze possibly plugging the exhaust if the output temp is below zero. There is a reason the heater is designed to have exhaust Temps above 100 C
You need to drill and tap a small 1/4" fitting into the lowest point of the radiator to drain the acidic condensate out otherwise it'll sit in there and eat away at the steel and eventually leak out through the rust holes it'll make. The 1/4" brass fitting can have a drain line that can be run outside so that condensate build up will drain on it's own.
Brilliant & comments, what about using copper pipe which runs ( attached ) through aluminium square plates spaced close together, heat then could follow wherever the pipe ran, eventually through to outside of wall, - just a " maybe " idea : )
Since you remove so much heat what about exhaust condensation in the radiator and since even after an hour it was showing a negative number could water build up and freeze close I would check outside to see if it is dripping. I am no expert but I would have thought there water some water in diesel that could condensate. Anyone please correct me if I am wrong.
That's a brilliant idea, but a few suggestions: Have the exhaust enter from the bottom of the radiator and exit from the top. Also the exhaust should enter on one side and exit from the other. If the exhaust gets too restricted incomplete combustion will occur.
No. If the exhaust enters from the bottom, there is no way to get rid of condensation. Condensation occurs when the exhaust drops below 100C. There is a reason the exhaust temp from the heater is above waters boiling point. Why enter one side and exit the other? He already showed that he is extracting all the heat from the exhaust, so much that his exhaust Temps are below zero, causing the condensation to freeze in the radiator.
@@ColCurtis Physics Still a closed system. If what you stated was true, eventually the exhaust would become blocked from the freezing condensate, filling the room with exhaust gases and killing everyone inside. Ever see an air compressor tank condensate valve? That is the ONLY proper way to drain the system. Every other way relies on pressure. The freezing readings were from the outside of the pipe, where the outside air was flowing into the area and over the outside surface of the pipe not from the exhaust gas exiting the pipe.
@@stans5270 if he keeps the bottom exhaust pipe temp above freezing the condensation will run out the bottom exhaust pipe. It is not a closed system if the bottom pipe is open. I would Insulate the bottom pipe to keep it room temp.
outside the radiator air raises because radiator is hotter than incoming room air. Inside the exhaust gases descend because radiator walls are colder than incoming exhaust gases.
That is incredibly efficient. I always thought the pumping the heat outside was extremely inefficient. That radiator almost makes it like using a mass rocket stove heater. I think if you put some ducting behind the radiator and ran a fan into the ducting it would heat the room even faster or at least keep all portions of the room the same temperature. Thanks for sharing. Best Wishes & Blessings. Keith Noneya
What if you add a pair of vehicle electric radiator fans (slim) behind the outlet radiator, running slow to dissipate the heat when it’s fully hot. Also heat reflect foil behind too. P.s. Great idea.
I bought one 6 years ago. The pump finally stopped pumping so I ordered a new one at $15. I really wish they would bring the heaters that warmed the fluids to Canada.
I heard the pump can fail if the fuel lines are soft rubber. It's recommended to use hard lines, apparently better both for the pump efficiency and lifespan (the lines included with most kits are cheap soft lines)
That was cool! Could you have hooked the exhaust to the bottom of the radiator first and then run a longer pipe from the top of the radiator down and to the outside? The idea being to keep the exhaust moving in a downward direction, as others have discussed at length.
The idea to have the exhaust moving in a downward direction is also safety reason, if the chamber get flooded with fuel it should drain out by it self. And if the exhaust pipe inside and the gases stays well above 60 C it will dry out the pipe but maybe not the radiator, even if outgoing gases from that stays well above 60 C.
A concern I would have is the any carbon monoxide in the exhaust would tend to hang around in low spots. With hot exhaust the CO would tend to disperse better. Stay safe!
You might do better with a vehicle radiator that doesn't have as much mass. Also a large pan under the diesel heater to capture a accidental diesel fuel spill.
Exhaust gas’s will want to go up not down, so you are fighting nature by pressing down hot fumes. Wire it differently with input down and output up. Then the radiator will be hotter down, with will heat upwards with the natural flow, producing more warming energy.
You are better off using a heat exchanger from the air heat outlet end of then Diesel heater with a water tank pumping water through the radiator or even set up underfloor heating pipes using the same water tank reservoir system... I did this to my Van build and it works great... Excess heat goes to a second heat exchanger for my hot water for washing-up and shower needs.... in the summer time i cut off airflow to the underfloor heating and still have hot water from my lagged tank....
Great Idea! One point to consider. By replacing the galvanized pipe at the bottom with a plastic pipe and fitting, if possible, would reduce the heat loss at the base of the radiator. May or may not be worth the trouble, but that is what came to mind. Thanks for the video!
@@hansmuller1625 It is a thermal bridge. Cold wind will cool the pipe, and the pipe will pull cold from the cooled end from the outside to the inside. Steel is a 300 times better conductor than wood. But this setup is probably not an optimized solution anyway.
DEATHTRAP! Heat is not a substance and therefore does not rise. Hot gases rise due to changes in density. The answer provided is also incorrect. The exhaust gases contain liquid (water and sulphuric and carbonic acids). These would build up in the radiator and block the exhaust, causing incomplete combustion and poisonous exhaust gases to accumulate in the room. As set up, this will also happen in the exhaust outlet. I'd be surprised if this guy is still alive.
I run mine through a 3meter flex exostpipe attached to a hanging piece or aluminum flashing and right before it gose out side i have it raped to the meter intake to warm the incoming air. It steams really good outdoors.
this is a very very good idea and works perfect. thanks i try lookig for a radiator myself now to try warming my shet much better. thanks very much for sharing.
If a person doesn't have access to the diesel that farmers use for tractors and such, can we use ordinary diesel from a gas station? That diesel vehicles use?
yes, the diesel that farmers use is the same but just has a dye in it to distinguish the two. The dyed diesel is cheaper because there is not a "Road Tax" on the fuel and is only intended to be used in off road situations like combines, or equipment. The tax on normal diesel is intended to be used as road maintenance.
@@logansteed1204 Wow! I had no idea about that. Thanks for that info. While I just bought, last week, a propane torpedo style heater for the garage, I'm now heavily leaning towards one of these diesel ones. I'll have to investigate, but I'd like to see if it's possible to mount it outside, in a protected box or something and just have the large heat pipe go into the garage. I'd rather do that so that there's no open flame INSIDE the garage where I may be working on the CRV, snow blower or motorbike. I'm actually nervous that I got this propane heater and in fact, I think that I'll return it and just get one of these. Thanks for the info.
@@BlondieHappyGuy you can for sure mount it outside in a protective box, however you will certainly lose efficiency by doing that because it will take the cold air from outside and blow it over the heat exchanger then into your garage. When its mounted inside it uses the already warmed air to blow over the heat exchanger. I'd definitely recommend insulating the box really well if you're planning on mounting outside. Keep in mind the air that goes over the heat exchanger is sperate than the air used in the combustion chamber so there shouldn't be any exhaust fumes if your exhaust is vented properly and all exhaust connections sealed. The intake for the combustion I'd also recommend routing outside. With what ever heating option you choose, id recommended a carbon monoxide detector or two placed around your garage to give you that peace of mind because propane or any other fuel other than hydrogen will always give co or co2 as a byproduct. A company i work for uses the expensive Webasto name brand ones to heat their insulated mud trucks in the winter. They work really well, how ever after lots of research it seems these Chinese heaters are almost as reliable at a fraction of the cost, which makes them a no brainer for causally garage heating and the overland/camper van people.
I have to say that this is one of the best ideas I have seen on RUclips. Of course condensation will form in the rad, but being cast iron and the exhaust low, it will drip out the bottom. Those heaters burn so efficiently that you won't have to worry about soot collecting in the rad. To test for this possibility, when it's new, record the temperature drop from top of rad to the bottom. After running it for months, or years, keep testing the temperature difference. If soot is forming on the inside of the rad, the temperature difference will become less. The exhaust temperature, at the floor will increase. The soot will act as an insulation. I can't see that happening though because of the burn efficiency. I only thing I would do differently is a more positive, sealed connection between the iron pipe and the heaters' flex line. Easy fix. As for the haters in the comment section, these people are shocking ignorant to basic science. You can tell they have done nothing in life. Nice job. It has given me some ideas.👍
I totally agree with @daveunderwood6498. The only comment I would make, and I'm being picky , are the 90 degree elbows but they do save space and that's the only a minor restriction .
Thank you very much for this nice comment. It's very motivating to read something like that and especially to see that people actually think about it. You're certainly right about the connection, although that causes more problems on the heater side than on the radiator side. The heaters are made so cheaply that a professional connection of both elements is a major challenge. Essentially and generally necessary. There is no point in connecting to the flex line with a hard-soldered flange if a stupid pipe clamp is supposed to seal the system at the other end. I chose the aluminum tape as a temporary solution as I'm still experimenting with this system, and I have to say after two years it's still tight and in very good condition. I haven't poisoned myself with CO yet and I don't need rubber boots for the condensate that forms as my other Diesel Heater vodeos prove LOL
No such word as “haters”, might disagree but they don’t hate! MAGA!
Ive been doing this for 3 years with an old steam radiator, have many videos about it here on YT. It works fantastic, no condensation problems as the armchair quarterbacks and internet experts always bring up. I have over 1000 hours of use with no issues, you want the exhaust from the heater to go in on the bottom of the radiator, exhaust out the top port which allows convection and hot air rising to remove condensation. The large internal volume of the steam radiator prevents backpressure so the combustion fan doesnt work too hard like it would with a long exhaust run, the hot air convection from the heater exhaust coming in from the bottom and exiting out the top (in my system) propels the exhaust out without putting undue work on the heaters fan, it also allows the stored heat in the thermal mass to continue to remove moisture even when the heater is off.
how much diesel does it burn per hour ?
Good read, I havent installed mine yet. I did read the exhaust MUST be down. I like reading someone who has actualy done this
Interesting - I have a heat exchanger to rig up to my Webasto exhaust that will share a coolant loop with the radiator circuit. Trying to get the pipe as short as possible before entering a 3inch full exhaust system - for the same reasons as you've explained.
@dancarter482 That's awesome, I remember seeing a commercially produced heat exchanger unit specifically made for diesel heaters on *David McLuckie* YT channel, as well as DIY versions using EGR heat exchangers or coils of copper etcetera...very interesting indeed. The unit that comes to mind was this fella who built the most amazing converted army truck RV-he uses both a woodstove and a diesel heater to warm his hot water tank as well as the coolant loop for the diesel engine, its quite a slick setup:
ruclips.net/video/y8vKhf1p1Lg/видео.htmlsi=mfY0eX63LbbP1oRP
How does condensation not end up sitting in bottom of radiator? Or are you saying the heat vaporizes it and pushes it out with the exhaust? Seems like the down draft shown here would simply allow the moisture that's created to flow out with the exhaust at the bottom. Or are you saying the condensation that is created simply does not create any problems?
Many people who watch this video are of the opinion in their comments that heat rises upwards, which is physically correct, but cold falls downwards, which also creates a downward suction in the radiator. That's why the entrance is always at the top and the cold that occurs when it cools down doesn't have to fight against the rising heat.
On a car radiator the hot water inlet is at the top and on a household radiator the inlet is always at the top to achieve optimal heat exchange.
It is also correct that you should not make the exhaust pipe too long, otherwise the resulting flow resistance will be too high, but given the flow cross section and the length of the components installed here, this shouldn't really have an impact. Since the difference in height between the exhaust gas outlet and the radiator inlet is approximately 45 cm or 18", there is virtually no back pressure. An exhaust silencer would generate more back pressure. And with an exhaust gas temperature of over 150 degrees Celsius, there is guaranteed to be no condensation in the pipe On the contrary, it will evaporate and condense again in the radiator where this condensate can then drain downwards. It is absolutely likely that deposits will accumulate somewhere in the system, but the solution to this is regular maintenance and cleaning.
Every boiler, fireplace and chimney must be cleaned regularly, even Chinese diesel heaters are not maintenance-free forever.
I like your design and am planning something similar...after seeing a bunch of Tubbers designs I think an oil or car radiator would be most efficient but I worry about corrosion. My idea is to run the exhaust thru a honda or toyota radiator and have the fan cycled with a fan relay in the heater, but i wonder how long it will last w/o antifreeze. That one your using is designed to run water through isn't it? an oil radiator might not last with water going through it either.
@@autojohn-pu1vf how about radiator that just all pipe pipe connectors the the think stuff like in this video
@@dh2032 I"ve seen some fellers on the Tube do that but it looks like a hassle... leaning towards getting salvage yard rad/fan and hanging a CO detector on it , with frequent inspections.
pipes are more expensive now than a cast radiator for 50 bucks
People think that but it's simpler than the rise and fall. Hot always moved towards cold. The thermodynamics of thermal energy is straight forward with that
Channels like this represent exactly how RUclips can be so useful.
For this to work, long term, you need to have the exhaust pipe from the diesel heater well above the radiator, so the condensation will flow down and out, through the radiator, as vapor. The way you have it set up, currently, the heater will eventually clog.
I was going to write the same remark. All the condensation will stay in the exhaustpipe the way it was set up.
Maybe fit the exhaust to the bottom and do the pipe on top through the floor?
The temperature in the flex pipe going from the heater upwards to the radiator is so high that you don't get condensation there. Maybe a few drops at startup but it evaporates as soon as it gets up to working temp. I have the flex pipe going upwards in my boat and have had no issues in the five years I've used it.
WRONG ....There is no condensation once the heater is up to temp (a couple mins) and any condensation that collects in the radiator will drain out. By your logic every vertical exhaust on every diesel engine ever would plug up.
Just to agree with the others, you can't have an exhaust pipe going up the way. It'll just fill up with vapour and condensation It must constantly go downhill. for this to work long term. If you look at the silencer. even that has a hole in the bottom to get rid of vapour for that very reason. You will need to raise the heater. or to have a Lower. Radiator. In principle, it should work OK then. The other option. is to use. a part from a car. I think they call it EcG. It allows you to pass the exhaust through. a water chamber. and then send the water through the radiator. That could work on your existing radiator so long as you have the exhaust at floor level. as it enters its heat exchanger. You would just need a small expansion chain. literally tiny. nothing bigger. than the size. on a car. Radiator top up. and it won't even need to be under a pressure. So long as it's at the right height.
@@chrisharrell2449 You really don't have a clue what you're talking about do you.
On a Russian site a man did this and did a lot of calculations based on the actual heat values - he concluded the heater itself produced just over 4kw on high and his radiator added a further 1.5 kw making a total of a little over 5.5kw - in another of his posts, he concluded that the 5 and 8kw heaters were in most cases the same!
Good use of old cast iron radiator. One Major Flaw with exhaust fumes exiting building. Even though your building barely sits above concrete pad , carbon monoxide fumes with hang next to floor and will leach back up through your high temp wool, as well as between seams between floor sheeting. You should have extended beyond building a foot at least and away left or right of window. Remember CM KILLS.
Diesels don’t make much CM, that being said you’ll still die, you’ll just die before any monitor will warn you. However that’s not even my biggest issue, the intake for the heater itself is INSIDE, it’s like hooking the intake from your car to the cabin. That should speak for itself
Carbon monoxide goes high, carbon dioxide goes low .
I have my heater exhaust hooked up to a 40 plate flat plate heat exchanger connected to my boats hot water tank. The heater heats my boat, the exhaust heats the water. It works amazing.
It heats the 9 gallon tank from 70F to 130F in under 90 minutes. As long as the water is above 70 I I’ve no issues with condensation or soot.
I should mention the water thermo siphons through the exchanger, meaning the water is constantly at 180 approximately. I also remove the exchanger often to make sure it’s clean and remove any condensation.
I love your idea.
Thanks for sharing.
I am looking for a unit to heat my sailboat and then in winter, transfer the setup to my truck and also pre warm the engine, and you just solved the problem.
I am a heating tech and have access to many different stainless steel heat exchangers.
You made it all come together, buddy.
Thanks
Great idea, the only downside is the condensation created by combustion which is going to collect at the exit of the exhaust gases because you have it running uphill. But even if it was plumbed differently, it would be trapping condensation throughout. But if it stops functioning, it’s because that bottom exiting section is too full of water
How people think the pipe can collect water with a tepereatur from over 220 degece Celsius the pipe is still nice and clean after 2 years no problem with it.
I would have figured someone would have caught on to all these comments about diesel combustion creating condensation. Now if it was gasoline then yeah it will have to be drained
Did the same thing, works fine, as long as you reduce the amount of fuel, with the default settings, the heater is running rich because off, the reduced exhaust air flow, if you keep on running it with default settings, soot will build up and clog your heater.
Make sure you can drain the radiator because the exhaust is humid and going through the rad it will condensate the water in it, unless the output is right at the bottom. . Place a few computer fans blowing against the rad to dissipate some of that heat into the room. Also you should be getting fresh air from outside because you are using the air in the shop and exhaust is pushing that air out so to compensate for the air going out, it will draft into the shed from all the cracks
I ran exhaust in to the bottom side of my cheap wood stove, it captures all the exhaust heat and the fumes go out the chimney pipe. I can still use the wood stove when needed.
Now that's a great idea....
I wonder if virtually any size metal box would work happily? Maybe a big ammo box?..
Me too thats also what i did😂
Brilliant, this is way better than what I had planned because that cast iron rad will also act as a thermal mass, which will continue to keep things warm a little longer, even after the heater shuts off.
Convert the radiator to a simple heat exchanger..
Fabricate a pipe that passes through the radiator from top section, looping to the lower and out as you have done with the existing exhaust path. That then allows the radiator to be filled 95% with water [for expansion, don't seal it!], giving more mass to capture the heat.
If you've a pump that can handle near boiling water temps you can then add more radiators to the system.
Very interesting video. And a real bonus for us viewers. No annoying, irritating, loud background music. except for a little at the end of the video. 👍
When I first installed my diesel heater in my caravan, I connected the exhaust directly to a 3 meter length and steel 1.5" water pipe, then out through the floor, the water pipe 3" above the floor is 190° and is awesome for keeping that heat inside instead of heating up the atmosphere lol, I could have made it go around the room further.
Great idea! Since the unit and the exhaust path is inside, please make sure to have a small space carbon monoxide detector (they are made for inside of small spaces like airplanes and semi trucks and are more sensitive) inside the shop/shed. I agree with the comment that the outside exhaust outlet should be extended past the building side (instead of just down under the shed floor - ideally up past the roof peak). Also, keep an eye on the temp of the pipe going through the floor to ensure the mineral wool is taking any residual heat before it reaches the flooring wood (thinking of a chimney wall/ceiling collar and how it separates the combustible surfaces from the heat of the exhaust pipe). Nicely done!
You do not understand why monoxide is creating. Stop giving idiotic advice if you don't understand the rules.
@@jacekolejniczak8726 Anywhere you have a union or join in a combustion exhaust run indoors, you want a CO detector. You also don't want to exhaust any combustion equipment simply down through the floor unless it continues outward well past the building.
So he sounds a lot smarter than you do, especially since he's given good advice and all you've done is make a dick of yourself without providing any input or backing up your comment at all.
I don't have one ,but finally, someone captured that wasted heat. Great job!
Many folk have done similar things with these heaters some much safer than others, but i don't remember seeing a vid which addresses the potential corrosion issue.
Hello from Windsor NS! That idea is exactly something I was thinking about, now you aren't wasting all of that heat!
Simply Genius!!! Works perfectly as these diesel heaters use a forced burn. Radiator is a steam radiator so any condensate will only happen in the lower section as water vapor is naturally drawn to cooler surfaces! Any water that collects in the bottom will eventually be blown out due to the forced airflow. ❤️💯❤️
Yes as the other comment say you should definitely have your heater exhaust higher than the radiator. The exhaust should never go uphill it will trap condensation and damage the heater long-term. In principle it's a very good idea but not executed correctly exhaust should go in the top and out the bottom of the radiator on the opposite side.
if anyone wants a cheap super simple way to extract heat from the exhaust, just buy a pack of scotch bright stainless steel scrubbers. You can expand them from the middle and slip them onto the exhaust pipe. They have a ton of surface area and conduct heat from the pipe really well. they work pretty well already by passive heating, but you can add a fan to help a little. You can buy a 16 pack for $10. Thats all you need.
Nice idea
Careful about back pressure. If you can, expand the exhaust pipe before you do this because if you plug the exhaust, the burner blower will start to force air out the sides of the exhaust instead of straight out
@@aaronwalsh7266 I’ve had this for years, I don’t get why the exhaust will get plugged up? The steel mesh is on the outside.
That’s a good idea, just wrap it around the exhaust yeah? I’ve just bought one of these heaters it’s coming this week I’ll give that a try cheers 🍻
Great idea 👍
I'm so glad you did this. I was planning the same set-up with a heater I just purchased and have a radiator already. Thank you for proving concept.
Much love
better go for a stainless steel pipe with slightly larger inner diameter as your exhaust hose and root the exhaust gas through that. I use a 2.6m long pipe that simply goes through the room and then exits with a slight downward slope. The pipe then just goes through the wall. The end of the pipe is at around 30°C so i get the same efficiency with much less effort and dont even have corrosion problems. I put a small bucked that collects the condensate under the exit of the pipe outside of the building so the sulfur does not go into the environment. The whole thing cost me around 30 bucks.
Ive had mine running in my garage for five years now, I think I'll try this when I reorganize later this year. the other benefit would be to hold the heat when the heater turns off, that much iron should remain hot for a while.
One more thing to consider - taking outside air trough recuperator. Now you are creating lower pressure inside room and outside cold air is leaking through cracks
Thank you for making this. I’ve always thought the exhaust made so much waste heat in diesel heaters. Rv heaters etc. Awesome to see you come up with a way to harvest it.
Nice idea to recoup the heat lost by the exhaust, but I would have turned the unit around to have the heat vent also blowing through the radiator. This would have a two fold benefit: 1. it would help to heat up the thermal mass of the cast iron radiator quicker, and 2. Once up to operating temperature the hot air passing through the fins of the now heated radiator would distribute the heat from the radiator better. On a side note, I would definitely add a 90° elbow to that exhaust under the shop and run it out from the perimeter of the shop (the rockwool may help where you drilled the hole, but there may be a couple seams on the underside to let fumes back up into the shop).
Not really. Heat inside is what matters. If you transfer heat to other objects changes nothing .....unless it increase heat radiated to the outside, which it might. Capturing exhaust heat helps but dumping heat into a cast iron heat exchanger instead of aluminum is less efficient but better than just dumping it.
something else to consider is the intake air to the combustion chamber, take it from outside. Else you consume the hot air from inside the building and cold air will leak in from outside.😇
Problem you are going to have with this setup is condensation in the radiator. The condensate is very acidic so it will rust that radiator though in no time. You can get round that however by using a stainless steel radiator. Also you need to have the exhaust coming out of the heater going down into the radiator so there is no chance of condensate collecting in the tube. I have a similar setup myself except I packed the exhaust radiator in sand as thermal storage so I can turn off the heater and get several hours of residual heat.
I’d say that’s a really cool idea. I never could understand these haters having so much loss of heat out the exhaust. Great idea!
It is 25-35% more efficient, not 200%, but I can understand your excitement 😉. The exhaust of a diesel heater wastes 0.1 to 0.7kW of energy depending on the heat setting of the heater. The 5kW heater is actually a 3kW machine. You can pass the exhaust through a bucket of water and you get hot water.
I was thinking the same.
Im thinking about building a CH system with water ( as I already have with nat. gas ) and exactly as you said, run the exhaust trough the water for extra heating efficiency.
it was more like a 3.3kw now it is a 4kw machine
25-35% more heat is still a lot.
Yes the 4kW is being sold as 8kW 😂. Can't complain, better than 3.3kW! @@NightshiftCustom
@examplerkey there all rated at 5kw but they like to lie and say 8kw. pretty normal for anything from China and even then there really only about 4kw. But there is a newer model that is about 6kw rated at 8kw and has a bigger burn chamber with a 3.5" outlet but only a few company's are selling them. There is also a smaller 2kw model available
Great idea! I would have the exhaust coming into the bottom of the radiator as this would allow the moisture from the engine to rise out the top as steam.
thanks, that's a great idea, and what makes it even better is I have a small cast iron radiator sitting unused in the basement. I am quite satisfied with my little diesel heater, but I have been thinking of a way to recover the heat lost through the exhaust because my shop is quite a bit too large for the poor heater (20ftx30ft) and I live in a cold climate.
Now that is a good idea......I thought about directing the exhaust to a sand battery, but the radiator idea is much simpler.
Put a small fan to blow on the radiator to move more heat
A meter of standard exhaust, always going down or sloped downwards, with a small fan blowing on it will yield room temp exhaust at the end with no carbon. Also have the intake on the inside air to limot the effect of having to heat the air too.
I made a recouperator for mine with a 3m coiled section of the same exhaust tubing. It's got a riser section coming out of the heater and coils downward to the outlet. No fan, purely convective. Exhaust temps at the recouperator outlet are around 40c and just as you're experiencing, no soot. I was surprised as I was expecting at least some soot. I get lots of condensate as evidenced by the large puddles the thing makes, but I'll take a puddle with the extra BTUs. Its a garage I'm heating. Puddles there won't hurt anything.
I'd have used an EGR cooler to transfer the waste heat to water. If you don't need hot water, you could use a car oil cooler with a small fan to extract the waste heat into the air. Same principle as your cast iron rad, but much more compact.
I'm not sure how you calculate a 200% increase in efficiency. You've not made any energy / volume calculations.
Also, I'd advise that you put a 14.8 volt 10 amp power supply on that battery to keep it from cycling. That way, you'll never have to worry about it going flat, and you'll have heat for hours if you lose grid power.
This is an elegant way to capture exhaust heat. I am now shopping for an old radiator!.Nicely done!
Heat in at bottom, but slightly above a condensate weep hole drain to not plug heat inlet.
Gasses will escape from any holes in the exhaust or radiator
Great idea. Good thinking on putting inlet at top so that condensables can drain out the bottom.
Test done on an Artic blog established that a claimed 5kw "Chinese" diesel heater gave 31/4 KW on full and a further 11/4 KW could be recuperated from the exhaust by passing it through a large radiator - a 38% improvement not 200%
A Russian post did some tests on this type of heater and found that the 5kw produces just over 3kw and adding a radiator on the exhaust added not quite 11/4 KW - he based his results on fuel used calorific value
Good to see someone else in NS doing stuff like this besides me. LOL Been using these CDH for a while. You will have issues with carbon build up eventually and condensation building up with the exhaust angled upward like that. Everything on the exhaust should be on a downward slope to prevent condensation build up and giving it a path to drain. Also move the combustion air intake outside of the space, when it does foul up it and it will at some point it will dump all the exhaust gases back through the intake manifold into your room because the intake and exhaust share the same combustion space. CO monitors are a must. Stay safe and good luck.
Intake should be outside, it really pulls air. The way he has it pulls air in through every crack in the building....
Yes the combustion air intake should always be outside. When inside they will pull cold air in from the outside through every crack and crevice it can because of negative pressure. I have seen the result first hand from my own mistakes and experiments over time.
That's an ingenious idea! I've got another idea for you that might also increase efficiency. Make a shroud for the back of the radiator and then hook the heated air hose to that so the already heated air is used to make a forced air setup for the radiator as well
concur
The one fault with the system is that the heater and exhaust pipe is below the entrance to the radiator creating a trap for moisture
Indeed...I have the same system..my heater is placed outside in a plastic nice box and the exhaust pipe is coming in at the top of the radiator and goes out at the bottem. My heater is at the highest point and the exhaust pipe is running down so water can run out at the bottom of the radiator.
Yes exactly, everything has to flow downhill or you could have water build up and flow restriction.
That exitpipe is so hot that it will vaporize any water/moisture there
If the temperature is over 190 Celius, wouldn't any moisture be vapourised? Once cars reach normal temperature, you don't see any moisture coming out of the exhaust pipe.
Antikk8191..?Whaaat? The heater burner exhaust pipe moisure gets heated but has nowhere to go but in the radiator to then condense at colder end.
I did the same, output pipe is a flexible plastic hose for sink draining.
Great job, BUT.... the exhaust outlet is designed to run at a typical specific 45 degrees.. there abouts downward . This downward slope from outlet through exhaust pipe to tip into muffler is needed to allow exhaust pipe to drain moisture to weep hole in muffler, note muffler needs to have it's weep hole facing down to drain... moisture from system. You directed your exhaust in the opposite direction.. this will surely trap moisture in your line and your radiator system..
Expecting it will last a couple of years, then rust through.
@@plinble nope, this make buildaps in exhaust and in heater, so this may not las even one year(depend on usage)
White PTFE tape is meant for non-corrosive liquid and gasses, the Blue PTFE os for corrosive gases and liquids. I'd take it apart and use the Blue before the White tape degrades and leaks gasses into your space... Also, heat rises, so heating should be at floor level, whereas cold sinks, thus AC should be at ceiling level. ☺☺
There might be even better way. Diesel water heater. Plum it into one more cast iron radiator and use aquarium pump to circulate the water mix. Two radiators would stay warm even after burn cycle. Especially one filled with hot water.
BTW exhaust hose should never go up according to manufacturer.
I think you'd be able to increase the efficiency by using outside air for the combustion air intake instead of indoor air. You're creating a negative pressure space, drawing cold in inside the building. Outside air will combust the fuel just as well and wont create a negative pressure. In the end you'll use much less fuel to heat the indoor air.
Should feed exhaust into bottom of the rad and out on the other side bottom. Heat rises. Rad would be heated way more evenly. Plug the top fitting. And no galvanized pipe in exhaust, too hot, zinc fumes released over time.
Other than that - well done.
the water build up needs to drain out the bottom
@@NightshiftCustom it also does not flow very well when frozen.
I would recommend putting a CO alarm that gives you actual CO read out.
Great video. The one thing that concerns me is Carbon Monoxide collecting under the shed and creeping back in. Did you put an elbow underneath with another pipe to take it away from the building?
Thank you for sharing your awesome exhaust heat capture solution. Everyone stay safe, warm, happy and healthy. From Henrico County Virginia
Its my understanding that there is moisture in the exhaust so the radiator will fill with very acidic water
It will go out at the bottom pipe more or less, but yeah, this is a valid concern.
I’m also concerned about the build up of soot as the exhaust condenses on the interior walls of the radiator. Also he could put a fan directed at the radiator to pull more heat from it.
Please check the other Videos on our channel
If your exhaust temp is lower than 140° it will condensate which is acidic which WILL rust that radiator out faster than you think. If the rad was stainless you wouldn’t have that problem. This is exactly the reason high efficient furnaces / boilers/ hot water heaters cannot use regular tin exhaust vents, they have to be able to resist the acid which is present in consensate. Master plumber/gasfitter 25yrs
I have one of those heaters. Why does the top of the radiator show 45°c & the bottom -4•5°c? I know heat rises, but I would have expected around 20°c at the bottom. Maybe it's because the radiator is cast iron & it takes far more energy to heat it up thoroughly. I know my friend uses a slimline pressed steel radiator & it heats up fine, albeit the bottom only heats up to half of the top temperature. Here is just a tip. He found that by having the air intake in his workshop, the heater wasn't working to its absolut potential, so, he put the air intake outside & found it worked much better therefore producing more heat. Anyhow, thanks for sharing. 👍
Produces the same heat with outside or inside air. But the inside air that it sucks to burn and then goes out the exhaust to the outside creates a very slight vacuum in the room, and then the cold outside air seeps in from every possiible crack and hole, countering some of the heating. Using outside air prevents a vacuum from forming since you are taking outside air for combustion and exhausting it outside, maintaining a pressure balance.
You could also build a sand battery and run the exhaust through that to prvide a thermal mass that will carry on pushing out heat after the heater is turned off.
I was thinking the same thing, a sand battery could be done incorporating a built in copper tube wound heat exchanger for hot water as well.
So many 90 turns on exhast before radiator. Build up in radiator. Aluminum foil. Make your exhaust straight line between radiator and bunk heater, add slow big fan on your radiator.
If you want to improve efficiency, I'd start with an intake duct and intake-exhaust heat exchanger: every cubic meter of ambient air used for combustion is a cubic meter of cold outside air that gets drawn inside and needs to get heated back up, much like single-hose portable ACs. If you dump all of the exhaust heat into combustion air drawn from outdoors, you eliminate the draft and the warmer combustion air also helps the diesel vaporize faster so it can burn cleaner. That is how high-efficiency boilers achieve their ~95% figures, nearly all of the exhaust heat gets absorbed by replacement air.
You can also use some of the exhaust heat to pre-heat the diesel by ~100C to help vaporization for a cleaner burn too. When liquid or solid fuel hits the flame, the flame has to put in the remainder of specific heat to get fuel to the boiling point, latent heat of vaporization to turn it into vapor and activation energy to ignite it. Pre-heating the diesel saves the flame from having to do most of the boiling part the work in what little time the fuel spends inside the combustion chamber. You still get the scavenged exhaust energy back in the form of a slightly hotter and cleaner burn since the flame has more net energy left in its exhaust for heat exchangers.
BTW, don't use an IR thermometer on shiny metals, readings can be waaaaaay off. Especially if there are other strong IR sources nearby such as the heater's direct exhaust pipe at ~180C: you may be getting a temperature reading from reflected IR instead of whatever you are pointing at.
The first broblem I see is the heater is not above the radiator to drip away moisture remember how they are fitted in RVs the exhaust always runs down to drain and with that size of rad you are gathering a lot of obnoxious gases.
Exactly! It's not gonna work for long, so this tutorial is misleading. I once installed longer exhaust pipe, and it was only slightly bent upwards in the middle and it was enough for the unit to stop working. When i detached the exhaust and bend it to the ground lots of moisture came out
well thank you for this fantastic plan. I started looking for a radiator right away, I found a old ornate one that came out of a house on york Street in Halifax. We're takin this rad to the camp! great idea! thanks again
I would add two hose clamps, to that Aluminum tape, for safety.
Seems very good heat recovery. It's good that you exit straight down thru the floor so condensation goes out with the exhaust.
One thing I would love to see done is to preheat the combustion intake air from some sort of heat exchanger with the exhaust. I'm thinking it would make the fuel burn better but not having one (yet) to experiment with I do not know.
Enjoy your warm shop!
Only 3things i would change is (1) have the unit higher so the exhaust is always flowing down in case of condensation, and (2) I would do a better job of sealing off the exhaust through the floor, maybe spray foam or calk, and (3) hook up a trickle charger to the battery.
Now have the blowing end of the heater blowing across the radiator to pick up that heat and also move the air inlet to the first part of the radiator at the hottest part so it is picking up the hot air will make the heated air hotter. If you understand what I am saying. Sort of a loop system making it help itself heat better.
From your friendly local heating guy (TSSA licensed )
Please dont do this....
That cast iron radiator is not meant to control products of combustion.
Teflon tape is not heat rated....
That exhaust through the floor will definitely seep back into the building, and, will create a ton of moisture under the floor causing wood rott.
The concept is absolutely correct, but this is a big carbon monoxide risk.
The guy is koo koo ka joo!
Also as a Tessa licensed tech I second this strongly
something tells me he's eaten enough paint chips as a kid that a little carbon monoxide poisoning is the least of his worries.
Can you explain more? What's wrong with having a radiator on the exhaust end? If there are no leaks and he has a detector if leaks happen later? Why can't he exhaust through the floor and elbow out past the side of the building?
@@remyllebeau77 The exhaust can run through the floor, in vehicles (where these are intended to be installed) the exhaust always goes through the floor, unless you have one of these chinese things. But that hole in the floor has to be sealed to prevent poisonous gasses from entering the building. Stuffing rockwool that rodents will remove does not count as sealing the whole lol.
Yes, you can have a CO2 detector, but if you how important is your life? I wouldn't install something that will leak, and rely on a detector to wake me up.
Then there's the issue of corrosion inside of the radiator, carbon build up, and all kinds of things that this dude is clueless about.
You need to add a drain valve to get rid of condensate building up in your radiator. Alternatively, use a more modern type (sheet metal) and tilt it so the condensate can exit via the exhaust.
Your first
section of exhaust pipe will fill up with condensate and block the pipe as it's going "up" to the connection on the old steam heater.
It is 100++ degree hot It can boil water rather than condensate
The outlet needs to slope downward so that condensed water can drain out.
@@Dave5843-d9m Correct, that's the biggest problem here.
Nice idea - I may give that a shot. I think you definitely need some kind of drain for condensation, though. You are dropping the air temp down to well below condensation temp by the time it exits the radiator, so I am betting you will soon have the bottom of the radiator full of fairly acidic condensate, which will likely do some significant damage to the internals of the radiator in the short term if you don't have a way to drain it. The cast iron would last a century if you ran clean water through it, but letting acidic water sit in the bottom will do significant harm to it.
Even if the radiator cast iron holds out, you will eventually be dumping that acidic water out onto your cement slab. If you don't want to put in a drain, I would think about pouring in some thin epoxy like the stuff mean to repair pinholes in gas tanks, and flipping the radiator around until it is coated inside evenly. The epoxy may give you some extra time before the radiator bottom perforates.
Thanks for the great idea!
All that heat does come.from the exhaust, and this looks bloody genius 👌
Got one in last year's lobster boat. And in that -40 it kept the snow and ice off the wheelhouse off the #CrissyG boat
6:30 😅
Dumb question of the day
Why knot plumb the exhaust in to the bottom as it would heat the rad up more quickly??
15:00 the little red one we hat, has the option to be set with a timer of when to atuo start
because if it cools down the condensat falls down and would fill the heater and it would be againt the flow => my video comment at the top
@dsfarmns2823 OK, that makes good sense, didn't really think about the condensation
Interesting idea, I just ordered mine. Ill be running exhaust through a muffler i bought for my chevelle. It arrived with a dent so they sent me a second one free. Sol i can use the large surface to exchange the exhaust heat....
This is a really bad idea that could be fatal from CO poisoning.
I won't nitpick your math, but I will warn you of letting the exhaust temperature fall below 212F inside of a metal pipe. Sulphur is a byproduct of burning petroleum based fuels, and if will react with surrounding gasses and forms sulfuric acid that will condense on your metal pipes and you will start getting holes in your radiator.
Guess what other gas is formed when you burn hydrocarbon based fuels?
Solution: Install a CO detector
True, check for holes in the radiator in ABOUT TEN YEARS.
@@SuperDirk1965 Unfortunately, we might be taking weeks to months with heavy usage... especially if it all completely condenses on the walls of the radiator.
@@joelhacker8767 Indeed, check for damage to the radiator in ten years. It's a cast iron radiator. Do you know how thick those walls are. The exhaust pipe going into the radiator will be long gone before that radiator springs a hole. Even the heater may be worn out by then.
I'm going to use some flexible dryer duct and put it around an extended exhaust (I already have both) and run a small DC fan at the bottom of the heater where the exhaust starts and split it off before it goes outside. I should be able to nearly double my heat output from 1 heater depending on the CFM of the fan.
I think the idea is brilliant BUT I feel you're Heater unit must be located higher to allow the condensation to flow down & out of the radiator outside,
The way it is at the moment your creating a U loop with no way for the condensation to run away .
At this point is no condensation never please watch the update video
If the exhaust temp is above the boiling point of water, no condensation can occur. However, he will get condensation inside the radiator, and it will freeze possibly plugging the exhaust if the output temp is below zero. There is a reason the heater is designed to have exhaust Temps above 100 C
You need to drill and tap a small 1/4" fitting into the lowest point of the radiator to drain the acidic condensate out otherwise it'll sit in there and eat away at the steel and eventually leak out through the rust holes it'll make. The 1/4" brass fitting can have a drain line that can be run outside so that condensate build up will drain on it's own.
or install it sloped
This is genius!! 👍👍👍
On a lighter note... put a fake Akrapovic sticker on that radiator 😉
Brilliant & comments, what about using copper pipe which runs ( attached ) through aluminium square plates spaced close together, heat then could follow wherever the pipe ran, eventually through to outside of wall, - just a " maybe " idea : )
Since you remove so much heat what about exhaust condensation in the radiator and since even after an hour it was showing a negative number could water build up and freeze close I would check outside to see if it is dripping. I am no expert but I would have thought there water some water in diesel that could condensate. Anyone please correct me if I am wrong.
That's a brilliant idea, but a few suggestions:
Have the exhaust enter from the bottom of the radiator and exit from the top.
Also the exhaust should enter on one side and exit from the other.
If the exhaust gets too restricted incomplete combustion will occur.
No. If the exhaust enters from the bottom, there is no way to get rid of condensation. Condensation occurs when the exhaust drops below 100C. There is a reason the exhaust temp from the heater is above waters boiling point. Why enter one side and exit the other? He already showed that he is extracting all the heat from the exhaust, so much that his exhaust Temps are below zero, causing the condensation to freeze in the radiator.
@@ColCurtis Physics
Still a closed system.
If what you stated was true, eventually the exhaust would become blocked from the freezing condensate, filling the room with exhaust gases and killing everyone inside.
Ever see an air compressor tank condensate valve? That is the ONLY proper way to drain the system. Every other way relies on pressure. The freezing readings were from the outside of the pipe, where the outside air was flowing into the area and over the outside surface of the pipe not from the exhaust gas exiting the pipe.
@@stans5270 if he keeps the bottom exhaust pipe temp above freezing the condensation will run out the bottom exhaust pipe. It is not a closed system if the bottom pipe is open. I would Insulate the bottom pipe to keep it room temp.
Wouldnt it make more sense to pipe the exhaust to the bottom opening of the radiator since heat naturally rises upward???
outside the radiator air raises because radiator is hotter than incoming room air. Inside the exhaust gases descend because radiator walls are colder than incoming exhaust gases.
could you use a radiator for a car with a fan behind it blowing the heat around the room ? or would it get too hot and melt the soldier joints?
Hope no one builds these without CO alarm nearby…
That is incredibly efficient. I always thought the pumping the heat outside was extremely inefficient. That radiator almost makes it like using a mass rocket stove heater. I think if you put some ducting behind the radiator and ran a fan into the ducting it would heat the room even faster or at least keep all portions of the room the same temperature. Thanks for sharing. Best Wishes & Blessings. Keith Noneya
What if you add a pair of vehicle electric radiator fans (slim) behind the outlet radiator, running slow to dissipate the heat when it’s fully hot. Also heat reflect foil behind too. P.s. Great idea.
I bought one 6 years ago. The pump finally stopped pumping so I ordered a new one at $15. I really wish they would bring the heaters that warmed the fluids to Canada.
I heard the pump can fail if the fuel lines are soft rubber. It's recommended to use hard lines, apparently better both for the pump efficiency and lifespan (the lines included with most kits are cheap soft lines)
That was cool! Could you have hooked the exhaust to the bottom of the radiator first and then run a longer pipe from the top of the radiator down and to the outside? The idea being to keep the exhaust moving in a downward direction, as others have discussed at length.
Yep
The idea to have the exhaust moving in a downward direction is also safety reason, if the chamber get flooded with fuel it should drain out by it self.
And if the exhaust pipe inside and the gases stays well above 60 C it will dry out the pipe but maybe not the radiator, even if outgoing gases from that stays well above 60 C.
A concern I would have is the any carbon monoxide in the exhaust would tend to hang around in low spots. With hot exhaust the CO would tend to disperse better. Stay safe!
You might do better with a vehicle radiator that doesn't have as much mass.
Also a large pan under the diesel heater to capture a accidental diesel fuel spill.
Just a thought when your showing videos with temperatures you may want to toggle your temp monitor between C and F to show both
Exhaust gas’s will want to go up not down, so you are fighting nature by pressing down hot fumes. Wire it differently with input down and output up. Then the radiator will be hotter down, with will heat upwards with the natural flow, producing more warming energy.
You are better off using a heat exchanger from the air heat outlet end of then Diesel heater with a water tank pumping water through the radiator or even set up underfloor heating pipes using the same water tank reservoir system... I did this to my Van build and it works great... Excess heat goes to a second heat exchanger for my hot water for washing-up and shower needs.... in the summer time i cut off airflow to the underfloor heating and still have hot water from my lagged tank....
Great Idea! One point to consider. By replacing the galvanized pipe at the bottom with a plastic pipe and fitting, if possible, would reduce the heat loss at the base of the radiator. May or may not be worth the trouble, but that is what came to mind. Thanks for the video!
Actually there's no point in doing that. That length of uninsulated pipe just adds a tiny bit to the surface area of the radiator.
@@hansmuller1625 It is a thermal bridge. Cold wind will cool the pipe, and the pipe will pull cold from the cooled end from the outside to the inside. Steel is a 300 times better conductor than wood. But this setup is probably not an optimized solution anyway.
i like how any condensation in your heat reclaiming exhaust just would continue safely out the floor no buildup❤
Heat rises, so why would you not have the hot exhaust enter from the bottom and exit at the top?
That way you waste heat, by having the exhaust at the bottom, the exhaust will be much colder and more heat will go into the room.
@@Mariano.Bernacki hm, I guess you're right. Didn't think about that.
DEATHTRAP! Heat is not a substance and therefore does not rise. Hot gases rise due to changes in density. The answer provided is also incorrect. The exhaust gases contain liquid (water and sulphuric and carbonic acids). These would build up in the radiator and block the exhaust, causing incomplete combustion and poisonous exhaust gases to accumulate in the room. As set up, this will also happen in the exhaust outlet. I'd be surprised if this guy is still alive.
I run mine through a 3meter flex exostpipe attached to a hanging piece or aluminum flashing and right before it gose out side i have it raped to the meter intake to warm the incoming air. It steams really good outdoors.
Tell me how many times you cleaned the heater from soot. And how do you plan to clean the radiator from soot?
this is a very very good idea and works perfect. thanks i try lookig for a radiator myself now to try warming my shet much better. thanks very much for sharing.
If a person doesn't have access to the diesel that farmers use for tractors and such, can we use ordinary diesel from a gas station? That diesel vehicles use?
yes, the diesel that farmers use is the same but just has a dye in it to distinguish the two. The dyed diesel is cheaper because there is not a "Road Tax" on the fuel and is only intended to be used in off road situations like combines, or equipment. The tax on normal diesel is intended to be used as road maintenance.
@@logansteed1204 Wow! I had no idea about that.
Thanks for that info.
While I just bought, last week, a propane torpedo style heater for the garage, I'm now heavily leaning towards one of these diesel ones.
I'll have to investigate, but I'd like to see if it's possible to mount it outside, in a protected box or something and just have the large heat pipe go into the garage.
I'd rather do that so that there's no open flame INSIDE the garage where I may be working on the CRV, snow blower or motorbike.
I'm actually nervous that I got this propane heater and in fact, I think that I'll return it and just get one of these.
Thanks for the info.
@@BlondieHappyGuy 🤣🤣
you can use kerosene in them, its easier to get hold of and runs the same
@@BlondieHappyGuy you can for sure mount it outside in a protective box, however you will certainly lose efficiency by doing that because it will take the cold air from outside and blow it over the heat exchanger then into your garage. When its mounted inside it uses the already warmed air to blow over the heat exchanger. I'd definitely recommend insulating the box really well if you're planning on mounting outside. Keep in mind the air that goes over the heat exchanger is sperate than the air used in the combustion chamber so there shouldn't be any exhaust fumes if your exhaust is vented properly and all exhaust connections sealed. The intake for the combustion I'd also recommend routing outside. With what ever heating option you choose, id recommended a carbon monoxide detector or two placed around your garage to give you that peace of mind because propane or any other fuel other than hydrogen will always give co or co2 as a byproduct.
A company i work for uses the expensive Webasto name brand ones to heat their insulated mud trucks in the winter. They work really well, how ever after lots of research it seems these Chinese heaters are almost as reliable at a fraction of the cost, which makes them a no brainer for causally garage heating and the overland/camper van people.
That was a great idea and good way to upcycle an old radiator!!
Nicely done too!