Brick acid is by far the best value and it works great. Always making sure, if the customer opts for clean over replacement, there's no guarantee on how long the fix will last.
Interesting video Alan I use a ultrasonic cleaning bath with fernox DS40 I have been cleaning plate heat exchangers this way for many many years they take approximately 30 minutes to an hour depending on how bad they are, the ultrasonic bath I use will hold about 10 plate heat exchangers at one time, I used to use a small one which would do a single plate heat exchanger at a time but then opted for a large one, I always found water/chemicals always finds its own way so you are not 100% guaranteed to clear a plate heat exchanger as the chemicals can go round the blockage, where as using a ultrasonic bath literally turns the blockage in the plate heat exchanger to dust with out pitting the plate heat exchanger you could use the bath without chemical but it would take longer without the DS40
It takes longer - but white vinegar (5% ascetic acid) is both safe and biodegradable - and does a good job of descaling the HW (secondary) side of a plate heat exchanger. I have a full-flow isolating valve and a washing machine Tee installed in the flow and return under my boiler, so I can power flush the DHW side without even needing to remove the boiler cover. In the USA this seems to be normal practice - and the required valves appear to be fitted at every install as standard. You have to wonder why the same is not true here in the UK.... I'll be flushing mine with vinegar annually from now on. (Cost of 5l of vinegar is about £5.00!) For the primary side , I decided to flush the system again, despite having done a mains water flush only a few weeks ago... This time however - inspired by this video - I tried to do something close to Allens' method. I closed all the radiators except the one nearest to the boiler. I drained a litre or so from that radiator then added Sentinel X400. This meant I was flushing the heat cell and primary of the flat-plate exchanger with a solution 10x stronger than If I was adding the X400 to the whole system ( +- 100 litres) I got the CH going at full blast on that one rad. Then switched to HW for a while and then back to CH. Within 10 minutes I saw the boiler temperature dropping to more reasonable levels!! I'll be keeping the flushing fluid in for a few days at least - and hope this will be enough to really clean-out both heat exchangers as well as the diverter valve . BTW I have a magnetic filter fitted, and have hardly any magnetite showing up at the moment, and the liquid is mostly clear - so I thought the whole system was clean. Maybe not quite as clean as I had hoped - but much better now!
Alan you are an absolute star! I live in New Hampshire in the United States and I have a Baxi Luna HT 1.330 combi boiler that was sold over here as a Laars Mascot. Combi boilers are very rare over here and and hard to find people who will work on them. I also live in a remote area. I watched your video and went to bed thinking that when I woke up I would be pulling the heat exchange out which i wasnt looking forward to. But when I got up this morning I thought maybe there's a method that I can back flush it while it's still installed similar as done to swimming fool filters. My radiant floor heating system is all Pex tubing coming out of the boiler. So what I did was cut the CH supply line coming out of the boiler which in my case goes directly to an external heat exchanger tank. I put a T fitting in the line with a 1/4 turn valve on the branch. Output of the valve facing the floor. With the boiler off and the valve closed, I then refilled the boiler to 2 bar. Then opened the valve quickly to mimic a water hammer, shake rhings loose and drain. Loads of black sludge shot out. Repeated this process about 4 times till the water looked clearer. I then removed the diverter valve motor essentially putting it in DHW mode and did the same. While empty i spun the T fitting facing upwards and with a little ingenuity was able to put boiler cleaning and lubricating liquid in it. This liquid can stay in the boiler. I refilled it and now it's running better, quieter and more efficient than it has in 10 years! And I've got an easy way to flush it from now on. :)
Thank you for sharing your thoughts and information. I soaked my Linea 28 HW exchanger with Flomasta cleaner overnight. It was not very convincing and did not dissolve the deposits, but by the time I had finished flushing, I had lots of particles out and got the flow rate through both sides to be similar. I'm hoping for another 20 years out of that heat exchanger!. I wish I had seen this link for advice on chemicals before I started. Love your good honest style. Keep up the good work.
I have just done a Vitodens 100 with the dreaded rubber hoses (same one you have there) about 3 weeks ago. Genuinely the worst I have ever seen, and it even had a magnetite filter. Huge lumps of metallic debris right throughout the plate, and the main exchanger. Tried cleansers etc, but wasn't resolving the primary issue. Called Tim @ All About Gas (fairly local to you), after he finished laughing, sold me a bottle of heat exchanger cleaner. Has Hydrochloric acid and inhibitors in it. Honestly, I removed the plate, purely because I wanted to see if it was actually going to work. A very small amount of the chemical not only removed the lumps, but completely removed the black sludge, and was back to looking like a brand new plate. 100% transformed the boiler and brought it completely back to life. Boiler now throttles the power correctly, and at a supply flowrate of 13l/min, the fact it was cutting out proved how bad it was, and the main complaint was that it was triggering the chimney stat, as it just couldn't shift enough energy to bring the combustion temperature down. One shot and black diamond good, but never used anything quite as good as the stuff made for the job. I'll never be replacing a plate again for a blockage.
@@SalimKhan-gk1fh it was an all about gas own branded product. Absolutely amazing, albeit very strong. Just be used with care. All about gas Dewsbury are the guys to speak to. Tim is the guy I deal with.
@@iandonnelly542 Thank you for the information Ian did you put it in just a plate to plate or did you actually put the stuff in the boiler as well? I don’t mind stripping these viessmann boilers down they are quite easy to do. They always respond well to a good clean out
@@SalimKhan-gk1fh I took out plate, poured a dilute solution in it and left it do its work. After 20mins, emptied, rinsed, and repeated. Had to do it about 4 or 5 times, purely because of the sheer volume of debris in it. I then removed the main heat exchanger from the case, and did the same. I only removed it from the case for safety. For the 30mins more it took, it saved having acid flying in your eyes. The boiler is 100% working as it should and has been ever since (it was modulating far too early, shutting off the burner).
@@iandonnelly542 Hi Ian thank you for the valuable information it’s always interesting to know what other guys doing as I work solo myself so don’t get much input from other engineers, A lot of people complain about working on these boilers but in all honesty they are a lot easier to strip down then some other brands .nothing breaks ,nothing seizes and everything uncouples quite easily, would anyone prefer working on a worshitter Bosch!!? Even the main heat exchange it is quite easy to remove, I’ve always used spirits of salt and it seems to work okay for me I found that when I jet wash a plate heat exchanger I always managed to get about 50% more magnetite out. In Germany they fill these with deionised or demineralised water or in more colder climates with antifreeze, 2018 onwards the 100 series is now fitted with copper pipes however the European models are still fitted with rubber pipes as they don’t seem to have a problem with system water across Europe ,I have several in-service running on antifreeze and up-to-date not a single one of them has suffered from magnetite or sludge debris accumulated in the heat exchanger or rubber pipes!!
The underlying issue is the system water quality. Cleaning or replacing the P2P is only really a temp measure. If the systems plagued with carp and crud the plate hex will inevitably block up again. If the boilers installed in a hard water area the hot water ways of the P2P are usually lined with carbon limescale which reduces heat transfer. I only try clean the plate (with black swan drain cleaner) ex as a temp solution to get the customers water up and running. Great upload as usual Allen keep sharing your outstanding work & knowledge.😜
The biggest problem with those Viessmann boilers isn't the plate X, it's the hoses, I have cleaned many plates only to find the boiler still locked out on overheat due to blocked hoses.
Hello Allan love your videos keep it up mate. Considering doing a flush/clean for am elderly customer that has a Gledhill cylinder with a thermal store plate heat exchanger complaining she has no hot water this week and I am hoping it does the trick!🤞
Great video Allen, I’d rather repair then replace I’ve used both chemicals you mention, spirits of salts and one shot I like both chemicals Homebase is cheap of spirits of salts to be honest at around £3 a bottle One shot is Great and use that a lot. Plus it’s made in Hull Also I always have a big bottle of Kamco fx2.. I think that’s brilliant stuff especially for plate 2 plates I’ve seen that method if syphon into main heat exchanger and didn’t believe it, I tried it and it worked on a Worcester aswell Got to be careful with chemicals as curtains ones eat certain metals especially aluminum I have made a jig to use to flush boilers, basically a pump an hoses, add acid and flush through main heat exchanger but boiler only It works all the the time but can be awkward to set up... great video Allen, love seeing things like this
Hey I just cleaned one on a Worcester Greenstar I filled with bleach , ten minutes , good shake an flush through outside tap full pressure then repeat process with vinegar an 9 out of ten times works wonders , a klip lock plastic hose connector on outside tap seals well an blasts loads of black muck out , this one is for when only household items available :)
Blocked heat exchangers go back solely to a shoddy install. Heating Engineer fully up to speed in the area will know how soft / hard the water is and after the post install cleaning flush would dose the system with appropriate inhibitors to prevent scale build up. Extended warranties from manufacturers request annual service, this should include a test of the system water to prove the inhibitors are still working.
Hello Alan, interesting video 🙂 I have been checking my boiler & the heat exchanger has an arrow on it which is pointing down. Can it be installed the wrong way, that is upside down? Would this also affect the performance of the boiler? thank you
...thanks for the video . I have an old valiant Turbomax 837E boiler and the only things I have ever changed is the flue and the fan . Thats it . I now have a problem that the water pressure drops and needs topping up every 12 days or so . The other problem is the hot water is not hot how it should be . What advice can you give . many thanks
Great instructional video Alan, thanks for sharing with the community. Can you please tell me if Sentinel X800 is safe to use in my Main Combi 24 boiler? I am fitting a MagnaClean Pro 2 filter to my system and thought than it might be a good practice to give the system a chemical clean and mains flush before introducing X100 corrosion inhibitor. Thanks.
Can you put the cleaner into the filter or radiator directly and let it flow throughout the system or do you have to remove the heat plate exchanger and put it into the plate directly
hi Allen, thanks for explaining the heat exchanger, very informative. my issue is that the hot water from the taps/shower come out hot initially, then go cool/tepid and if i increase the tap flow, gets colder. the temp guage doesnt register anything either. could this be the same problem as a blocked exchanger? I do have a new one to fit anyways but waiting on a boiler engineer to turn up this week hopefully. hope you can shed light on mine. thanks Ideal mini C24. (central heating works fine)
Does this method clean both sides of the plate heat exchanger. I doubt that it will only clean the CH part but the PHE is more likely to be blocked or scaled up on the Hot water side.
It only cleans the heating side in the first part of the video. We do not really get too much scale here, Its normally down to boilers not installed very well and sludged up. Thanks.
Citric acid monohydrate dissolved in boiling water. Keep tipping the heat ex to allow gas to escape then top it up with a bit more of the solution. 15 minutes, done. Effective for plate heat ex"s that are scaled because of the constant topping up of a system.
I have to say I am a big fan of SOSalts I have used it a lot and it does a great job. Nasty stuff to use the fumes are really bad from the hydrochloric acid, so you need to be in a well ventlated place prob outdoors if possible. I have used costic soda as well but prefer the SOS. Great Vid thanks
Is it possible to connect a washer drainage pipe to a basin trap 32mm and if so would there be any issues or would it just work the same as connecting it to a sink trap
Ariston 23 MFFI MICROGENUS BOILER domestic water gets hot but at the same time the rads get hot as well [even though CH turned off] is that the heat plate or the diverter valves?
Hi Allen. Went to a Viessman Vitodens 050 with F2 fault. Turned hot water on and eventually got hot but hot water going down heating pipe? afterwards no hot water, combustion chamber still operating but no flame or hot water at all. Heating side not working either. Customer adamant it’s the heat plate exchanger blocked. What do you think? Cheers.
Can I use a 50 plate on a vehicle to have hot showers off road ? Obviously I would filter the water before. But would it work to heat water for showers ?
I have always taken the plate off & soaked the plate in a cleaner. How long would you run the x800 through the boiler while drawing on the hot water? This method is not possible on 837 no tube to vent the main hex.
For the moment (for the last 6-7 years) i use nerta ATC 300 . I'm still looking for a better product based on hydrochloric acid and hydrofluoric acid that is easily available in my country... I buy Nerta Atc 300 in 25 liter drums for ~ 70E ; and on large heat exchanger I neutralize it with baking soda...
Nice oven plate :D I use for descaling acetic acid (BIOMUS Lapex). U need to try TOPTHERM Clean F9 B (Foridra) for cleaning fume side of hex WB6 (Bosch, Wuuster, Buderus). Clean F9B is good for ALSi hex.
@@cliveedridge2350 how much do you charge to change heat exchanger and pipe on viessmann. Getting prices from 250 - 550 but nobody really seems interested in doing it.
Hi my boiler goes hot and cold all the time. And make crackling noise,And a boiler friend of mine said it could be the heater changer and it needs cleaning . Do you recommend that kind regards Mem
Hi mate my boiler Ideal logic the heating is working but hot water is coming out warm not hot at all even though the temperature shows is raising up what could be the problem please
Thanks for the video. For a Main Combi 30HE, can you remove the secondary heat exchanger and clean it like you've done the plate heat exchanger? Also, which of these tends to clog up first and why?
Hi , I have single pipe heating system and plumber toon Off bathroom radiator and wants to put two pipe fed radiator , id it even possible..... we also don’t have hot water or heating working anymore 😔😔😔😭😭😭
Hi allen i got new heat exchange plate 12 month a go how long do they last my boiler was services 2 month a go my system was clean but suddenly got noise when boiler heats up heating and water water is getting hot like it supposed to im baffled
Most rubber hoses are hydroscopic and entrain oxygen dont know why manufacturers insist on still using them? Vaillant learned that lesson years ago.was the only reason we moved away from the brand ,but to be honest most brands have some sort of achillies heal
Mike Barron It’s strange that in Germany and across Europe they don’t have trouble with sludge and magnetite the new generation viessmann vitodens boilers here have copper pipes now , the ones across Europe STILL use the original rubber hoses as they don’t seem to have an issue over there with them
Anybody know a rough price for changing heat exchanger and rubber pipe on viessmann. Got a couple of quotes but massive difference in price. Is it a chew to do because nobody seems interested in doing it. Thanks
Hi Alan. One question.If we use there strong chemicals its ok for the heating system part of heat exanger but I am a bit concern here about contamination because onother part going to hot water tap.How can you be sure that there are nothing left? Now I worked for a company and we placed MDPE main water pipe.And you know how you need to chlorinate the new pipe,give the sample of water to the water transporter so he would accept the cleanliness of pipe..It was a new pipe and we did 3 attempts of that.Were cleaning 6h each attempt. Only 3rd was clean enough for them..You see where I am going with this?Is it safe you fink to do it this way introducing chemical to drinking water?
Have you ever had a fault on a plate exchanger that leaks presurised boiler water into the DHW but only in one direction? This is possibly because the leak hole is only when the exchanger is hot and as soon as DHW demand stops the exchanger cools and the hole closes up? If the hole was there when cold I would expect the mains water pressure to keep adding water to the boiler and the pressure just keep increasing until the PRV opens (assuming that the water pressure is over 3 BAR). When the boiler is in central heating mode it maintains pressure and works normally but as soon as DHW is used the pressure starts to drop over time and this leads me to believe that this is the fault.
@@AllenHart999 Thanks, I have a new heat exchanger which arrived today. Did a test yesterday with all the hot taps out of use and isloated the cold feet to the boiler (trapping the water in the DHW side of the plate) no pressure loss in 24 hours so I think its 100% the plate.
Just to complete the thread, new plate heat exchanger fitted and this cured the fault. So what was happening was the pressurised boiler water was leaking through the plate, mixing with the DHW and going down the plug hole along with the inhibitor (the invisible leak). There was no pressure increase when the boiler was left standing which is the normal indication of a leaking plate so a hard one to find. The boiler by the way is a Vokera Linea Max year 2000. Hope this helps someone with the same problem.
Interesting video. Is it worth cleaning them tho'? My Vokera Unica 28 needs a new one, I've been quoted £340, but they retail for just over £30 so to me a replacement is worth the time and effort.
So syphoning into boiler isn't a bad idea as plates sent always easy to get out and back in without old seals leaking. I would take pressure out the vessel and pump back up to try and keep chem as neat as poss. Cleaning plates is really only a temp fix as there is usually a filthy system behind it
I agree it's the easiest way to clean main heat exchanger but if I ever attempt this I will only do it after a full flush of the system. Good videos👍 keep them up. Thanks allen
Fill the exchanger with boiling water or preheat before using chemicals. Use very cold water to flush it out, which will stress the copper and steel inside. As you can see in the video, there is very little space between the plates. This slight movement makes cleaning much more effective. Repeat this process several times.
Allen I remove them and take it to a local car wash blast em through with the power washer it works a treat , never had one fail yet it removes all the debris in a few minutes .
Hi Alan. Thanks for your videos. How long can you leave central heating cleaner in the system before draining down or power flushing? And what is the best cleaner/s? Thanks for your response in advance Best regards Mo
@@AllenHart999 Thanks. It does not say on the can. I know that X800 must not stay long. And when you clean the heat exchanger, how long do run the hot tap to circulate the cleaner inside the heat exchanger? Thanks
I don’t know a right lot about Alpha as a company but the very few boilers I have worked on look ok. I am going to try and get on a training course with them soon. Thanks
Hi Alan, enjoyed your video as always. I have a Viessmann vitodens 111, recently started going to F2 fault code. Only happens in HW mode, boiler works fine in heating mode. I’m thinking it’s likely to be the plate heat exchanger that is blocked up. Want to try cleaning it before I replace it. Just wondered if you think there is anything else I should be checking as well while I’m at it? Cheers
I am thinking that dettol for shower and bathroom might work great because it has some great chemicals in it. I know it works great for sediments, i cleaned my cars turbo with it, so can you make a video about it?
Wanted to try Spirit of Salts but it's more expensive so just good old One Shot for me. Cheap from the local merchants and normally does the trick. Haven't tried the siphon method to clean the main hex yet. I've seen Geoffrey Needs' video on it. Might give it a go next time. 👍🏽
Alan great video I have a back combi 80e been a great boiler with only a few minor niggles . I've noticed that there seems 2 different sized plate available for this boiler and I think one is for the bigger 105e is there any advantage in putting the bigger one in mine is would it improve the flow rate thanks
If using one shot remember to get the old formula as since acid attacks the new formula is useless on anything bar a very small sink blockage. Hopefully eBay sellers are importing the good stuff. Ps Allen do you charge less if you do the trick method as your not removing the heat exchanger?
Always watch your vids and have learnt alot and have improved my work alot so thanks Alan. I've always just replaced plate heat exchangers as its a guaranteed fix. The syphon trick is actually a really good idea and i will definitely try it! You said you saw it on a youtube video from a worcester engineer? would you mind sharing his name? Alway good to learn from others :) Thanks
Hi Alan. Thanks for the video. I'm interested in the economics of spending this much time on cleaning the main heat exchanger and plate heat exchanger without any guarantee of success. Do you charge for your time and chemicals regardless of the result? Would replacement parts be quicker, more expensive but a guaranteed result? Thanks
Hello Allen great video as usual thank you, I have a question about my old boiler, NOT THE WIFE LOL, It is a gloworm compact 100e that I have rescued so many times in the past and I know it is way past its shelf life but still purrs away apart from start up, It coughs and barks on start up, and after switching power off and on again it is fine, (HEATING ONLY IT DOES THIS) I feel it is some restriction in the heat exchanger, thank you from any advice apart from the ovious (NEW BOILER) ps I am a refrigeration engineer so my trade is opposite lol.
Brick acid is by far the best value and it works great. Always making sure, if the customer opts for clean over replacement, there's no guarantee on how long the fix will last.
Interesting video Alan I use a ultrasonic cleaning bath with fernox DS40 I have been cleaning plate heat exchangers this way for many many years they take approximately 30 minutes to an hour depending on how bad they are, the ultrasonic bath I use will hold about 10 plate heat exchangers at one time, I used to use a small one which would do a single plate heat exchanger at a time but then opted for a large one, I always found water/chemicals always finds its own way so you are not 100% guaranteed to clear a plate heat exchanger as the chemicals can go round the blockage, where as using a ultrasonic bath literally turns the blockage in the plate heat exchanger to dust with out pitting the plate heat exchanger you could use the bath without chemical but it would take longer without the DS40
That is a great idea.
Hi Steve can I ask we got an ultrasound cleaner big enough for a plate to go into??
many thanks
It takes longer - but white vinegar (5% ascetic acid) is both safe and biodegradable - and does a good job of descaling the HW (secondary) side of a plate heat exchanger. I have a full-flow isolating valve and a washing machine Tee installed in the flow and return under my boiler, so I can power flush the DHW side without even needing to remove the boiler cover. In the USA this seems to be normal practice - and the required valves appear to be fitted at every install as standard. You have to wonder why the same is not true here in the UK.... I'll be flushing mine with vinegar annually from now on. (Cost of 5l of vinegar is about £5.00!) For the primary side , I decided to flush the system again, despite having done a mains water flush only a few weeks ago... This time however - inspired by this video - I tried to do something close to Allens' method. I closed all the radiators except the one nearest to the boiler. I drained a litre or so from that radiator then added Sentinel X400. This meant I was flushing the heat cell and primary of the flat-plate exchanger with a solution 10x stronger than If I was adding the X400 to the whole system ( +- 100 litres) I got the CH going at full blast on that one rad. Then switched to HW for a while and then back to CH. Within 10 minutes I saw the boiler temperature dropping to more reasonable levels!! I'll be keeping the flushing fluid in for a few days at least - and hope this will be enough to really clean-out both heat exchangers as well as the diverter valve . BTW I have a magnetic filter fitted, and have hardly any magnetite showing up at the moment, and the liquid is mostly clear - so I thought the whole system was clean. Maybe not quite as clean as I had hoped - but much better now!
Alan you are an absolute star! I live in New Hampshire in the United States and I have a Baxi Luna HT 1.330 combi boiler that was sold over here as a Laars Mascot. Combi boilers are very rare over here and and hard to find people who will work on them. I also live in a remote area. I watched your video and went to bed thinking that when I woke up I would be pulling the heat exchange out which i wasnt looking forward to. But when I got up this morning I thought maybe there's a method that I can back flush it while it's still installed similar as done to swimming fool filters. My radiant floor heating system is all Pex tubing coming out of the boiler. So what I did was cut the CH supply line coming out of the boiler which in my case goes directly to an external heat exchanger tank. I put a T fitting in the line with a 1/4 turn valve on the branch. Output of the valve facing the floor. With the boiler off and the valve closed, I then refilled the boiler to 2 bar. Then opened the valve quickly to mimic a water hammer, shake rhings loose and drain. Loads of black sludge shot out. Repeated this process about 4 times till the water looked clearer. I then removed the diverter valve motor essentially putting it in DHW mode and did the same. While empty i spun the T fitting facing upwards and with a little ingenuity was able to put boiler cleaning and lubricating liquid in it. This liquid can stay in the boiler. I refilled it and now it's running better, quieter and more efficient than it has in 10 years! And I've got an easy way to flush it from now on. :)
Your videos are great, I learn a lot by watching them , and also allows me to improve my skills . Cheers from France.
Thank You
Thank you for sharing your thoughts and information. I soaked my Linea 28 HW exchanger with Flomasta cleaner overnight. It was not very convincing and did not dissolve the deposits, but by the time I had finished flushing, I had lots of particles out and got the flow rate through both sides to be similar. I'm hoping for another 20 years out of that heat exchanger!. I wish I had seen this link for advice on chemicals before I started. Love your good honest style. Keep up the good work.
I have just done a Vitodens 100 with the dreaded rubber hoses (same one you have there) about 3 weeks ago. Genuinely the worst I have ever seen, and it even had a magnetite filter. Huge lumps of metallic debris right throughout the plate, and the main exchanger. Tried cleansers etc, but wasn't resolving the primary issue. Called Tim @ All About Gas (fairly local to you), after he finished laughing, sold me a bottle of heat exchanger cleaner. Has Hydrochloric acid and inhibitors in it. Honestly, I removed the plate, purely because I wanted to see if it was actually going to work. A very small amount of the chemical not only removed the lumps, but completely removed the black sludge, and was back to looking like a brand new plate. 100% transformed the boiler and brought it completely back to life. Boiler now throttles the power correctly, and at a supply flowrate of 13l/min, the fact it was cutting out proved how bad it was, and the main complaint was that it was triggering the chimney stat, as it just couldn't shift enough energy to bring the combustion temperature down. One shot and black diamond good, but never used anything quite as good as the stuff made for the job. I'll never be replacing a plate again for a blockage.
Ian Donnelly sounds very interesting Ian so what was the stuff called that you used?
@@SalimKhan-gk1fh it was an all about gas own branded product. Absolutely amazing, albeit very strong. Just be used with care. All about gas Dewsbury are the guys to speak to. Tim is the guy I deal with.
@@iandonnelly542 Thank you for the information Ian did you put it in just a plate to plate or did you actually put the stuff in the boiler as well? I don’t mind stripping these viessmann boilers down they are quite easy to do. They always respond well to a good clean out
@@SalimKhan-gk1fh I took out plate, poured a dilute solution in it and left it do its work. After 20mins, emptied, rinsed, and repeated. Had to do it about 4 or 5 times, purely because of the sheer volume of debris in it. I then removed the main heat exchanger from the case, and did the same. I only removed it from the case for safety. For the 30mins more it took, it saved having acid flying in your eyes. The boiler is 100% working as it should and has been ever since (it was modulating far too early, shutting off the burner).
@@iandonnelly542 Hi Ian thank you for the valuable information it’s always interesting to know what other guys doing as I work solo myself so don’t get much input from other engineers, A lot of people complain about working on these boilers but in all honesty they are a lot easier to strip down then some other brands .nothing breaks ,nothing seizes and everything uncouples quite easily, would anyone prefer working on a worshitter Bosch!!? Even the main heat exchange it is quite easy to remove, I’ve always used spirits of salt and it seems to work okay for me I found that when I jet wash a plate heat exchanger I always managed to get about 50% more magnetite out. In Germany they fill these with deionised or demineralised water or in more colder climates with antifreeze, 2018 onwards the 100 series is now fitted with copper pipes however the European models are still fitted with rubber pipes as they don’t seem to have a problem with system water across Europe ,I have several in-service running on antifreeze and up-to-date not a single one of them has suffered from magnetite or sludge debris accumulated in the heat exchanger or rubber pipes!!
The underlying issue is the system water quality. Cleaning or replacing the P2P is only really a temp measure. If the systems plagued with carp and crud the plate hex will inevitably block up again. If the boilers installed in a hard water area the hot water ways of the P2P are usually lined with carbon limescale which reduces heat transfer. I only try clean the plate (with black swan drain cleaner) ex as a temp solution to get the customers water up and running. Great upload as usual Allen keep sharing your outstanding work & knowledge.😜
I have installed a new p2p and it lasted a few minutes in the past. As you say the system needs to be clean. Thanks.
For how long you keep the chemicals inside the heat exchangers?
What a great technic, I used it this morning, and it did it well.... so nothing else to say, than thank you Allen fort this tips :)
Brick acid -patio cleaner works very well found it to be the best so far you will need latex gloves
The biggest problem with those Viessmann boilers isn't the plate X, it's the hoses, I have cleaned many plates only to find the boiler still locked out on overheat due to blocked hoses.
I used oven cleaner in my diesel intake and its cleaned my turbo, dpf and egr valve with the vehicle running 1000 times smoother.
Superb videos Allen. Very informative, down to earth and easy to understand. Many thanks.
Hello Allan love your videos keep it up mate. Considering doing a flush/clean for am elderly customer that has a Gledhill cylinder with a thermal store plate heat exchanger complaining she has no hot water this week and I am hoping it does the trick!🤞
Great video Allen,
I’d rather repair then replace
I’ve used both chemicals you mention, spirits of salts and one shot
I like both chemicals
Homebase is cheap of spirits of salts to be honest at around £3 a bottle
One shot is Great and use that a lot. Plus it’s made in Hull
Also I always have a big bottle of Kamco fx2.. I think that’s brilliant stuff especially for plate 2 plates
I’ve seen that method if syphon into main heat exchanger and didn’t believe it, I tried it and it worked on a Worcester aswell
Got to be careful with chemicals as curtains ones eat certain metals especially aluminum
I have made a jig to use to flush boilers, basically a pump an hoses, add acid and flush through main heat exchanger but boiler only
It works all the the time but can be awkward to set up... great video Allen, love seeing things like this
Hey I just cleaned one on a Worcester Greenstar I filled with bleach , ten minutes , good shake an flush through outside tap full pressure then repeat process with vinegar an 9 out of ten times works wonders , a klip lock plastic hose connector on outside tap seals well an blasts loads of black muck out , this one is for when only household items available :)
Can this be done as diy, my vokera compact se boiler keeps cutting out even on low, suspect heat exchanger
Excellent video, thanks Allen!
Thank You
Blocked heat exchangers go back solely to a shoddy install. Heating Engineer fully up to speed in the area will know how soft / hard the water is and after the post install cleaning flush would dose the system with appropriate inhibitors to prevent scale build up. Extended warranties from manufacturers request annual service, this should include a test of the system water to prove the inhibitors are still working.
love your channel mate thanks for all your effort
Love your videos mate and your Yorkshire accents Allan
Great video again Allen keep them coming 👍👍👍👍
Thanks Allen, I hope work is starting to pick up again.
Brian Wood I have a few jobs booked in now, Thank you
Hi Allen, great video, can you syphon in ato a Baxi platinum 40... do you have a video for that pls ?
Been in trade for 50 yrs all yr videos Bob on look to c wats new and how others repair
Thanks for sharing Alan I found this video very informative
Glad it was helpful!
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Hello Alan, interesting video 🙂 I have been checking my boiler & the heat exchanger has an arrow on it which is pointing down. Can it be installed the wrong way, that is upside down? Would this also affect the performance of the boiler? thank you
...thanks for the video . I have an old valiant Turbomax 837E boiler and the only things I have ever changed is the flue and the fan . Thats it . I now have a problem that the water pressure drops and needs topping up every 12 days or so . The other problem is the hot water is not hot how it should be . What advice can you give . many thanks
shouldn’t be working on your boiler if u can’t diagnose those other faults… phone a gas engineer 🙃
Great instructional video Alan, thanks for sharing with the community. Can you please tell me if Sentinel X800 is safe to use in my Main Combi 24 boiler? I am fitting a MagnaClean Pro 2 filter to my system and thought than it might be a good practice to give the system a chemical clean and mains flush before introducing X100 corrosion inhibitor. Thanks.
Yes, absolutely
Can you put the cleaner into the filter or radiator directly and let it flow throughout the system or do you have to remove the heat plate exchanger and put it into the plate directly
This is brilliant. Cheers for doing the video.
spirit of salt and a good rinse with water always works for me
hi Allen, thanks for explaining the heat exchanger, very informative. my issue is that the hot water from the taps/shower come out hot initially, then go cool/tepid and if i increase the tap flow, gets colder. the temp guage doesnt register anything either. could this be the same problem as a blocked exchanger? I do have a new one to fit anyways but waiting on a boiler engineer to turn up this week hopefully. hope you can shed light on mine. thanks Ideal mini C24. (central heating works fine)
did you find the issue to your problem?
Yes but no Plumber would come to replace it so ended up buying a new boiler. Seems they don't like working on aged machines
Does this method clean both sides of the plate heat exchanger. I doubt that it will only clean the CH part but the PHE is more likely to be blocked or scaled up on the Hot water side.
It only cleans the heating side in the first part of the video. We do not really get too much scale here, Its normally down to boilers not installed very well and sludged up. Thanks.
Citric acid monohydrate dissolved in boiling water. Keep tipping the heat ex to allow gas to escape then top it up with a bit more of the solution. 15 minutes, done. Effective for plate heat ex"s that are scaled because of the constant topping up of a system.
Have you got a link to doing it on a Worcester bosch greenstar 24i junior?
Hello my friend can I ask what is the types of acid that we use to discale
Isn’t the chemical going through central heating system rather than water side on heat exchanger
How long do you leave S O Salts in for to dissolve the blockage. Does it dissolve gaskets aswell?
Thanks for the informative video.
I have to say I am a big fan of SOSalts I have used it a lot and it does a great job. Nasty stuff to use the fumes are really bad from the hydrochloric acid, so you need to be in a well ventlated place prob outdoors if possible. I have used costic soda as well but prefer the SOS. Great Vid thanks
Is it possible to connect a washer drainage pipe to a basin trap 32mm and if so would there be any issues or would it just work the same as connecting it to a sink trap
Not really.
I presume this is hard water areas Alan as I live in manc an it seems not a problem , if it’s sludge do you suggest a mag I clean on install ?
Ariston 23 MFFI MICROGENUS BOILER domestic water gets hot but at the same time the rads get hot as well [even though CH turned off] is that the heat plate or the diverter valves?
Hi Allen. Went to a Viessman Vitodens 050 with F2 fault. Turned hot water on and eventually got hot but hot water going down heating pipe? afterwards no hot water, combustion chamber still operating but no flame or hot water at all. Heating side not working either. Customer adamant it’s the heat plate exchanger blocked. What do you think? Cheers.
Can I use a 50 plate on a vehicle to have hot showers off road ? Obviously I would filter the water before. But would it work to heat water for showers ?
I have always taken the plate off & soaked the plate in a cleaner. How long would you run the x800 through the boiler while drawing on the hot water? This method is not possible on 837 no tube to vent the main hex.
30mins maybe. Thanks.
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For the moment (for the last 6-7 years) i use nerta ATC 300 . I'm still looking for a better product based on hydrochloric acid and hydrofluoric acid that is easily available in my country...
I buy Nerta Atc 300 in 25 liter drums for ~ 70E ; and on large heat exchanger I neutralize it with baking soda...
Nice oven plate :D I use for descaling acetic acid (BIOMUS Lapex). U need to try TOPTHERM Clean F9 B (Foridra) for cleaning fume side of hex WB6 (Bosch, Wuuster, Buderus). Clean F9B is good for ALSi hex.
Hi Allen I always take out the black hose on those vissemman combis aswell they are always full of crap
Do you do that on every service? Thanks.
Allen Hart
If it’s a regular customer every 3 years and certainly if they are signing up to my regular service
@@cliveedridge2350 how much do you charge to change heat exchanger and pipe on viessmann. Getting prices from 250 - 550 but nobody really seems interested in doing it.
@@davecrow9636 hi I charge £69 per hour
Hi my boiler goes hot and cold all the time. And make crackling noise,And a boiler friend of mine said it could be the heater changer and it needs cleaning . Do you recommend that kind regards Mem
Hi mate my boiler Ideal logic the heating is working but hot water is coming out warm not hot at all even though the temperature shows is raising up what could be the problem please
Thanks for the video. For a Main Combi 30HE, can you remove the secondary heat exchanger and clean it like you've done the plate heat exchanger? Also, which of these tends to clog up first and why?
How long should a license plate be soaked in hydrochloric acid? or spirits of salts?
Hi , I have single pipe heating system and plumber toon Off bathroom radiator and wants to put two pipe fed radiator , id it even possible..... we also don’t have hot water or heating working anymore 😔😔😔😭😭😭
Hi allen i got new heat exchange plate 12 month a go how long do they last my boiler was services 2 month a go my system was clean but suddenly got noise when boiler heats up heating and water water is getting hot like it supposed to im baffled
I like the syphoning trick. I will use that, thanks. You might want to do it once a month to the viessmann to keep those rubber hoses clear.😄
Thanks.👍
Tigerick I was shocked how much came out 😂😂😂 Thanks
Most rubber hoses are hydroscopic and entrain oxygen dont know why manufacturers insist on still using them? Vaillant learned that lesson years ago.was the only reason we moved away from the brand ,but to be honest most brands have some sort of achillies heal
@@mikebarron4929 All boilers have something as you say. Thanks for the comment.
Mike Barron It’s strange that in Germany and across Europe they don’t have trouble with sludge and magnetite the new generation viessmann vitodens boilers here have copper pipes now , the ones across Europe STILL use the original rubber hoses as they don’t seem to have an issue over there with them
Anybody know a rough price for changing heat exchanger and rubber pipe on viessmann. Got a couple of quotes but massive difference in price. Is it a chew to do because nobody seems interested in doing it. Thanks
Dave Crow It’s an absolute doddle of job and £250 including the parts would probably cover it
Hi Alan.
One question.If we use there strong chemicals its ok for the heating system part of heat exanger but I am a bit concern here about contamination because onother part going to hot water tap.How can you be sure that there are nothing left?
Now I worked for a company and we placed MDPE main water pipe.And you know how you need to chlorinate the new pipe,give the sample of water to the water transporter so he would accept the cleanliness of pipe..It was a new pipe and we did 3 attempts of that.Were cleaning 6h each attempt. Only 3rd was clean enough for them..You see where I am going with this?Is it safe you fink to do it this way introducing chemical to drinking water?
Have you ever had a fault on a plate exchanger that leaks presurised boiler water into the DHW but only in one direction? This is possibly because the leak hole is only when the exchanger is hot and as soon as DHW demand stops the exchanger cools and the hole closes up? If the hole was there when cold I would expect the mains water pressure to keep adding water to the boiler and the pressure just keep increasing until the PRV opens (assuming that the water pressure is over 3 BAR). When the boiler is in central heating mode it maintains pressure and works normally but as soon as DHW is used the pressure starts to drop over time and this leads me to believe that this is the fault.
It would normally be the filling loop left open a bit but yes the plate can sometimes pass. Thanks.
@@AllenHart999 Thanks, I have a new heat exchanger which arrived today. Did a test yesterday with all the hot taps out of use and isloated the cold feet to the boiler (trapping the water in the DHW side of the plate) no pressure loss in 24 hours so I think its 100% the plate.
Just to complete the thread, new plate heat exchanger fitted and this cured the fault. So what was happening was the pressurised boiler water was leaking through the plate, mixing with the DHW and going down the plug hole along with the inhibitor (the invisible leak). There was no pressure increase when the boiler was left standing which is the normal indication of a leaking plate so a hard one to find. The boiler by the way is a Vokera Linea Max year 2000. Hope this helps someone with the same problem.
@@Rondjrocket This is just what I was after. Got an Ideal logic with the same fault👍
If this gets blocked would it cause a noise like a kettle??
Kilrocl works well in hard water areas
Interesting video.
Is it worth cleaning them tho'?
My Vokera Unica 28 needs a new one, I've been quoted £340, but they retail for just over £30 so to me a replacement is worth the time and effort.
So syphoning into boiler isn't a bad idea as plates sent always easy to get out and back in without old seals leaking. I would take pressure out the vessel and pump back up to try and keep chem as neat as poss. Cleaning plates is really only a temp fix as there is usually a filthy system behind it
These heat exchangers sometimes start to block, Its a good way to clean the main heat exchanger. Thanks.
I agree it's the easiest way to clean main heat exchanger but if I ever attempt this I will only do it after a full flush of the system. Good videos👍 keep them up. Thanks allen
Chris Lewis Thank You 🙏
Fill the exchanger with boiling water or preheat before using chemicals. Use very cold water to flush it out, which will stress the copper and steel inside. As you can see in the video, there is very little space between the plates. This slight movement makes cleaning much more effective. Repeat this process several times.
Allen I remove them and take it to a local car wash blast em through with the power washer it works a treat , never had one fail yet it removes all the debris in a few minutes .
Wayne Brown never even thought of that, Thanks 🙏
Yes, I've pressure washed a few. It works great.👍
@@tigerick7291 I can vouch for that. Cleaned a plate at a mechanics house who had a power washer. Cleanest plate I've ever done.
Where would the scale and dirt go though?
Why do viessmanns plates black up quicker?
Hi Alan. Thanks for your videos. How long can you leave central heating cleaner in the system before draining down or power flushing?
And what is the best cleaner/s?
Thanks for your response in advance
Best regards
Mo
Depends what cleaner you use really. Always best to look on the bottle of the product. Thanks.
@@AllenHart999 Thanks. It does not say on the can. I know that X800 must not stay long. And when you clean the heat exchanger, how long do run the hot tap to circulate the cleaner inside the heat exchanger?
Thanks
@TheMt9398 the x800 can't stay more than 20 hours....
Allen what’s your opinion on alpha combi as opposed to the ideal logic Maz
I don’t know a right lot about Alpha as a company but the very few boilers I have worked on look ok. I am going to try and get on a training course with them soon. Thanks
Hi Alan, enjoyed your video as always. I have a Viessmann vitodens 111, recently started going to F2 fault code. Only happens in HW mode, boiler works fine in heating mode. I’m thinking it’s likely to be the plate heat exchanger that is blocked up. Want to try cleaning it before I replace it. Just wondered if you think there is anything else I should be checking as well while I’m at it? Cheers
I am thinking that dettol for shower and bathroom might work great because it has some great chemicals in it. I know it works great for sediments, i cleaned my cars turbo with it, so can you make a video about it?
Thanks for the tip!
Wanted to try Spirit of Salts but it's more expensive so just good old One Shot for me. Cheap from the local merchants and normally does the trick. Haven't tried the siphon method to clean the main hex yet. I've seen Geoffrey Needs' video on it. Might give it a go next time. 👍🏽
Umar K Very cheap on eBay. Thanks 🙏
Alan great video I have a back combi 80e been a great boiler with only a few minor niggles . I've noticed that there seems 2 different sized plate available for this boiler and I think one is for the bigger 105e is there any advantage in putting the bigger one in mine is would it improve the flow rate thanks
So would 5 mind be a maximum for both chemicals
Using very hot water and citric acid works well , plus citric acid is harmless
Hi Alan - Can these go on the wrong way when reinstalling?
I replace them depending how bad they are of course, I try to avoid all chemicals for my health and safety, i also give customer an option sometimes
How long is “a little while”?
Ive heard brick acid is very good at it , i just replace the part everytime. I dont find x800 bery good
I spilled one shot on my leg yesterday.. burnt right through my work trousers ! My leg is a mess
You ever fitted / recommend to customers a combisave?
E Andrews I had one at my last house but I haven’t installed one for a customer. Thanks
Tried the spirit of salts but it burnt through and caused the water feed to keep filling the system through the plate
Are the plate heat exchangers omnidirectiinal? Does it matter which way round you install them?
Yes
Many thanks Alan 👍👍
I'm about to do mine as its starting to whistle when I run the bath.
My glow worm boiler has hot water but no heating, don’t know what to do?
Call out a local Gas Engineer to test it. Thanks.
If using one shot remember to get the old formula as since acid attacks the new formula is useless on anything bar a very small sink blockage. Hopefully eBay sellers are importing the good stuff. Ps Allen do you charge less if you do the trick method as your not removing the heat exchanger?
U CAN USE VINIGAR OR APPLE SIDER.
Thank You
Always watch your vids and have learnt alot and have improved my work alot so thanks Alan. I've always just replaced plate heat exchangers as its a guaranteed fix. The syphon trick is actually a really good idea and i will definitely try it! You said you saw it on a youtube video from a worcester engineer? would you mind sharing his name? Alway good to learn from others :) Thanks
MrRichard44441990 I will add a link above when I get back home. Thanks 🙏
ruclips.net/video/Z2J9JXgOhNA/видео.html
@@AllenHart999 thankyou :)
All the chemicals that go through my powerful machine you would think it would remain clean but not the case 🤔
Love your video
Nice work 👍🏻
Could u name the guy you said does vids on Worcester please bud?
ruclips.net/video/Z2J9JXgOhNA/видео.html
Cheers mate, great vids by yourself, very helpful
Informative video that, good options to consider using.👍
Hi Alan. Thanks for the video. I'm interested in the economics of spending this much time on cleaning the main heat exchanger and plate heat exchanger without any guarantee of success. Do you charge for your time and chemicals regardless of the result? Would replacement parts be quicker, more expensive but a guaranteed result? Thanks
i always use FX2
Thank You
Hello Allen
great video as usual thank you,
I have a question about my old boiler, NOT THE WIFE LOL,
It is a gloworm compact 100e that I have rescued so many times in the past and I know it is way past its shelf life but still purrs away apart from start up, It coughs and barks on start up, and after switching power off and on again it is fine, (HEATING ONLY IT DOES THIS) I feel it is some restriction in the heat exchanger, thank you from any advice apart from the ovious (NEW BOILER)
ps I am a refrigeration engineer so my trade is opposite lol.
Knock out Sprit of salts. The only thing that works other then fitting new
I replace for new one