How to Install a Hot Water Recirculation Pump | This Old House
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- Опубликовано: 6 сен 2014
- This Old House plumbing and heating expert Richard Trethewey delivers hot water on demand. (See below for a shopping list and tools.)
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Richard helps a homeowner install a hot water recirculation pump to reduce the time she has to wait for hot water.
Shopping List for Install a Hot Water Recirculation Pump:
recirculation pump [amzn.to/2Loll4Z]
1 5/8-inch screws [amzn.to/2N7wysY]
Tools for Install a Hot Water Recirculation Pump:
mini-hacksaw [amzn.to/2NVsmfE]
adjustable wrenches [amzn.to/2NVmdQy]
drill/driver [amzn.to/2LrY6Y6] fitted with 3/4-inch-diameter spade bit [amzn.to/2NTGlSZ]
The pump that Richard installed is the D'MAND system, manufactured by Taco [www.tacocomfort.com/]
The kit includes all necessary parts and is available at plumbing supply stores.
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How to Install a Hot Water Recirculation Pump | This Old House
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I like how the electric outlet appears inside the vanity.
Andre Campbell magic!!
I see this a lot in the USA. For dishwashers etc
To be honest, not sure I see the huge risk with doing it even if it “feels wrong”
🇬🇧
You see this in Germany all the time. They usually have a small efficient water heater underneath the sink. Here in Romania, you have the outlets just outside the bathroom for electric razors, hair dryers etc. If you install anything inside the bathroom, an electrician has to bring wires inside somehow. Pain in the ass. Debatable...
Andre Campbell ya next will install a garbage disposer
Maybe it was that it " just appears" like magic. I've never seen an outlet under a bath sink unless added later. If your going to put a pump in, your going to have to add electricity with ground fault circuitry.
Modern kitchen sinks are more likely to have power for garbage disposal and dishwasher.
I've been following TOH since the early 80's. I'm always a skeptic, but in the end will say that Richard Tretheway is the man! Thumbs up to some of the OG's, and long live TOH! :)
Legend has it, she still has no idea where that hot water is going.
Bob Sacamano 🤣
It will take too many minutes to sketch the water pipes and explain piping and valves in the show.
He also didn't explain it. He did not explain that the pump has to have more pressure then the static water pressure of the home and the pump tries to push the water backwards through the main water line for the house. Basically pushing the water back to the city. My question is, would it flow the water meter backwards as it did it?
@@letsnotmakethispersonal6021 ..here's my guess....many homes have a backflow preventer or check valve that won't allow water that is "Already" in the home system....to be pushed back out into the city system. So....when the under-sink pump comes on, it has to have enough pressure to overcome the pressure in the home system, and it then pushes hot water from the hot water line.....into the cold water line. Remember.....if you are "taking" hot water from the piping ( and from the hot water heater, part of your home "System" inventory)...you have "room" to re-introduce that same amount of water back into your home system, but now it's being re-introduced back into the cold water section of the "system". Both hot and cold sections are part of the same system, and can flow into (and out of) the "System"...meaning all the house piping connected to the hot water heater....so there is room to put the same amount of water back into the cold water line....that you "took out of" the hot water line.
@@TheWilferch that, that right there would be an actual answer to her question. Thank you.
Brilliant idea. If your on a well/septic system you really need this.
Very smart idea. This would also work for a regular hot water tank that is located at the opposite end of the house where the hot water is needed.
I have been following "This Old House" since 1965. I have already been a big fan of this channel.
How many CFM's are we talking here?
You must have been in a time warp, since the show began in 1979.
This system works great in my home. I’m on a well and have a septic system. I don’t waste water my water by putting it into my septic system.
Surviving the California drought✌🏻
What brand do you have?
Richard is top notch!
Rich nice simple explanation, I sure need that too!
Perfect solution!
What brand and what model pump dos have the remote switch and hot water sensors
Thank you
Interesting solution!
This is a very nice & interesting video. Thank you very much for sharing your knowledge with us. But I don't know if I missed the information regarding the pump. Where can I buy it? or what's the model number? I haven't read all the comments and maybe I didn't read enough. Can somebody tell me that information?
Ive learned about this pump recently as a plumber, they have versions that the pump that needs power sits atop a water heater tank and you put a small device that slowly lets water into the cold side to keep water flow.
The other kind of circulating pump works like this. You find the furthest fixture and run a second hot water pipe from it that ties back into the heater
The pump then constantly pumps water thru that line and everything gets hot water faster.
As a plumber i would recomend useing a tank water heater with the kind of pump i explaines first. Tankless water heaters req alot more power than a tank and if its gas than alot more btu of gas than a tank heater.
The whole point of a tankless is to not be running all the time in the first place as it takes twice the energy of what a water heater with a tank would use to heat the water. Hope this helps, feel free to ask questions.
I agree, I hope my tankless install with a learning smart circ pump will save me energy over all (not using water from 730 am to 6pm)
Thinking how many times the burner on a tank style will turn on to heat sitting water during the day compared to tankless with 2 kids using demand from 6 pm to 9pm
(Food prep, washing hands, showers and baths)
Thoughts?
Andrey Yaromich you do know you can just not have the water heater running until you’re getting ready to come to around 6pm. My electric company even has a switch they control that can shut off the water heater for hours, during a time when it’s not needed.
@@andreyyaromich8277
less energy to maintain warm temperature in a TANK, rather then bringing cold to hot instantly
We have a recirculating pump like this in an upstairs bathroom with a tankless heater but getting hot water to the kitchen takes 10 minutes. Would you recommend a second recirc pump in the kitchen?
Does this pump work for regular conventional hot water tubs?
How convient that there is a 110 outlet inside the vanity. LOL yeah, that happens all the time.
I was thinking the same thing!
CUEBALL424 or lights
That’s why they call it a convenience outlet.
wait not just an outlet but a true GFI...LOL...how many years of energy savings to recoup the money spent on the electrician's bill
By NEC in any bathroom 110 GFCI outlet have to be no more than 3' away from vanity
In my experience, the success of the install is based on proper timer settings. If you keep the hot water circulating for too long you'll end up waiting for cold water just as long as you used to wait for hot water pre-install.
Wtf are you talking about?
No timer, push button.
It would also help to put insulation around the hot water pipe from the water heat to where the pipe goes into the wall and heads upstairs.
It also helps when you STFU
Depends on how frequently the hot water gets used and the length of the run.
Not really. If you only use the bathroom hot water every morning, it has 24 hours to cool down
Yea I’d say insulating works when you use the heater intermittently every couple hours, here in Ontario Canada, no insulation is required by code in new/permitted install on tankless.
But on a tank heater we have to install at least 8ft of quality insulation to pass inspection.
That’s what I asked. Why not insulate the pipes?
Which is better, this under the sink one.. or the recirculation pump at the hot water heater?
Since the tankless is an energy saving device, seems like some insulation around those hot water pipes would be in order, cause after you use up all that heat to get to the second floor, ut all disapates into the basement when done washing your hands or whatever else your doing.
you're
OR just install a Grundfos UP15-10SU7P/TLC and put the pump down stairs where most people would have a plug and the by pass in the cabinet. most tankless heaters have a recirc built in now though.
Insulation will slow down heat loss..it won't stop it. If there is zero flow, the water temperature will still cool to room temperature....only more slowly with insulation
Not really. I put one in in a new house and even with insulation it's worth it. My Chilipepper went out in 3 years and looking for this Taco but can't fine it and I like tacos but without chilis.
Will a recirc pump mess up a water softener by pumping water into the brine tank? I would imagine you install the water softener then a check valve then the tankless water heater with a recirculating pump on a dedicated line. Does thy sound right?
Great!! only if I had told the contractor to put in an outlet in the vanity!!
What brand circulating system did you install here and where did the push button and remote start come from. Doing some research and am not seeing these as part of a package.
thanks for the video, rich. i live in california and we're in the middle of a three-year drought, making it difficult to justify wasting clean water while waiting for it to get hot.
i like this on-demand recirc pump but can't find the make / model. can you tell me what pump you installed?
Legend has it doobie newell still doesn't know what pump to buy.
Did you ever find this pump? I'm looking for it too.
this very good system, but my question is this pump will help to empty could water in all bathroom or only for this faucet sink?
If you see it up like you are is it a dedicated unit just for that bathroom?? Does that mean I have to install at the other hot water lines to the other location.
Actually, what I said earlier (Commenting from the UK but I do have this problem - however, our cold water comes straight from the main line outside in the street - I don't have a cold water tank. Would this still work?), presumably the cold water goes into the hot water tank the same way it takes it from the outside?
My house was built in 2010 and have a tankless water heater. It take 2 minutes or longer to get hot water in the bathroom. So if I install one of these, will it take 2 minutes after turning on the hot water faucet to get anything? What about the dishwasher?
Please help find a model with manual on/off button capabilities anymore. I'd like to install either a wired or wireless button on the wall of the kitchen sink. I have a 5GPM tankless heater. Thanks!
Does this video include links to the parts used? The pump make, model ... Switch make model?
This one is the exact solution I am looking for - Can't seem to find it in Ontario Canada anywhere. Suggestions would be appreciated.
This is a pretty old thread if you happen to read this message, do you know where I can find recirculation pump that you are showing in the demo, all my searches are resulting in one that goes on the top of the water heater but I want something that can be mounted inside the cabinet. If you can post the link or make of the pump much appreciated.
Are going to place pumps everywhere at home to get the delayed hot water. If it is intended for that particular faucet then that would be a good fix. But for a complete solution for the house, you should have new pipe tapped near each master isolation valve at the house and the should all gather to a common point that discharges from recirculation pump given that pressure balance is achieved across all tapping points.
I've been plumbing for over 40 years. (since Jr. High School) I am so glad that most people just don't get plumbing. Keeps me working. Government codes and restrictions force plumbers to oversize water systems so that if everything in the structure was running at once....wait...that would never happen. To circumvent that piece of legislature I run a separate, dedicated 1/2" supply to the kitchen sink, where hot water is in demand most of the time. If you just undersized everything... the pipes will erode from the inside out.
Averageskill
-
surely not a licensed plumber., Water supply piping of both water heater and cold water is sized BASED ON Fixture value and based on PSI., so that it can be sized based on the REQUIRED Min amount of pipe sized. Don't know what you're talking about being FORCED to OVERSIZE. A house with 40 psi at the supply and 4 bathrooms surely need bigger piping than another home with 80 psi and 1 bathroom.
@@MrInfoPhilly _____You say: "Surely not licensed"
Aren't you forced to do the speed limit while driving?...but you do it anyway.
My comment addresses circulating systems which sometimes cause "pin holes" in copper. Also, having to wait a long time for hot water, wastes water (simple). For my customers who's water heater is located far away from the kitchen sink or shower, I run a dedicated 1/2" hot water line from the water heater directly to the fixture. Takes much less time to get hot and wastes much less water. (simple) No energy wasting and "pin hole causing" circulating pump ($300.00) needed.
I don't under-size water systems....I install custom features like dedicated lines so you don't have to wait for or waste hot water.
@@readmore3634
Reread your first comment., you use the word undersized, not me.
An appropriate size, in residential., I use (1) ½ line for the kitchen sink and dishwasher. Then tee off for the stubouts.
If we're talking water recirculating systems., one should use a variable speed pump and circuit setter to limit the gpm and all is good. Don't you think?
@@MrInfoPhilly I never said to undersize...I said " To circumvent that piece of legislature I run a separate, dedicated 1/2" supply "instead" of under sizing . That way you have no hot water running through any larger (than needed) pipe to reach the kitchen. As for circulating systems...a very slow running pump is fine in almost any system, provided the system is completely insulated....The problem is "electrolysis"....constant (unnecessary in most cases) movement of water in pipes. Electrolysis is unpredictable even if you use dielectric unions at every dissimilar metal connection.
What recirculator dis u instal in this video?? I need the info asap
Easy when you have an outlet inside the vanity! That hot water sure arrived fast!
how much more expensive bill a month for the pump vs without?
Commenting from the UK but I do have this problem - however, our cold water comes straight from the main line outside in the street - I don't have a cold water tank. Would this still work?
..sounds great..pays for itself in only 15yrs..cool
What is the pump brand that uses the on demand button, I can't seem to find anything on line that does not have a timer. I have to waste so much water waiting because of hot water heater locations and want to install this system
The description is not showing what make and model pump is being used...:-( From the looks it looks like a TACO unit. However I cannot find one with the switch mechanism to turn it on...
Can anyone help?
Does the recirculating pump have to overcome the house water pressure that would be present at the cold line return?
Genius
I am not sure I get this --- so, the cold water in the cold water line backs up through that cold water line to where the cold water supply line branches off to the hot water heater and takes that path to recirculate the water?
So, if you happened to turn on the cold water faucet in the lavatory when the recirc pump is one, is there a much higher pressure in that line when the recirculation pump is on trying to heat up the hot water line?
so you still have to wait for the hot water? or does the temp sensor keep working it all day?
can you provide detail information about the pump you are using in this video or similar pump please?
What is the name of the pump system he is installing?
which pump are you using in the video, your link goes to amazon with all kinds of pumps
Probably not likely to get answered, but the link to the pump he installed (would work great for my purposes) just goes to amazon general search for recirculating pumps, not the specific one he installed. :(
Anyone have a link or know what brand/model he actually installed?
Thanks,
RichE San Diego, CA
You will still get Luke warm water in the cold until the sensor reaches the hot setting?
Is there a link to this type of recirculation pump?
All it’s doing is connecting the new hot water return line which in this case is that set of tees that come with the pump and tying into the cold line with a aqua stat that opens or closes on your set temperature demand, and I’m sure there is a backflow or check valve built into the pump or the hot side tee that he used. So basically Instead of your traditional hot water return loop that starts at the furthest hot water fixture always from the water heater and runs all the way back to the water heater and connects into the cold water feed to the water heater , which helps also because you’re not dumping just cold water into the tank when using it but know it’s tempered since that hot water return ties into the cold right at the tank , of course there needs to be a check valve on the return line ,and some say the cold water line to prevent any type of cross connection
What's the brand and specs for the pump? What stores carry it?
Where do you buy the (remote control) parts?
But what if you have a pressure reducer or a backflow preventer?
Great
Can you use this with an electric tankless hot water heater?
There's too many comments to read and help clarify. So here's a little clarification.
What he meant about the 3/4" pipe not doing her any favors was simply that the 3/4" line has more than twice the volume as the 1/2" and therefore requiring twice the amount of cold water to clear before she got the hot water.
On the other hand, as someone mentioned 3/4" is (sometimes) required by code depending on the amount of water it is anticipated to pass. And on the 3rd hand, these tankless water heaters have a tendency to cause a sizeable pressure loss while using the 3/4" would make up for that pressure loss.
Tankless water heaters have a lot of pros and cons, which I won't get into here. Just google it.
In the long run you're typically not saving money. Likely will end up costing you more.
Another way to skin the cat is to connect the end of a Hot Water line to you toilet. What's the first thing you use when you get up in the morning and go to the bathroom? ;-))
I go to the site but I can't find this pump for my tankless water heater. Need a part number?
I understand the aquastat stops the pump once hot water reaches the sink and I also understand there is a check valve that prevents "cold water from crossing into the hot water side" when hot water is used. What prevents "hot water from entering into the cold water side" when cold water is used at the sink, shower, watering the lawn or any other cold water demand that lowers the water pressure in the cold line and not the hot line? If hot water is crossing over into the cold water side during cold water usage, wouldn't that place additional demand on my water heater.
The pump wouldn't be running, so the pathway would be closed. It is a pump, the flow only occurs while powered.
what was the brand name of the recirculation pump that was installed?
It's a taco and I can't find it on their website. Did you.
Works great IF you have an outlet under your bath vanity.
We need to know the make and model and where we can purchase the recirculating pump that Richard installed in the Sept 7, 2014 on Ask this old house show.
It is a Metlund D'mand
That's not right, Its a Taco
Where I can buy this pump?
That's a neat device but... I'm unclear on how it solves any problem... I suppose it saves a small amount of water, but it still takes around the same time to get the hot water right? also shouldn't those pipes be insulated?
I could understand if the recirculator was triggered by some measure of activity in the house... like change in electric usage or a motion sensor or something - but if you just need to click it regardless... hm. I guess I'd have to use one to really assess the benefits.
3:47 Watch It !!!
What is the name of the pump? I cannot ask for it if i don't know the name and model.
Copper pipe? What year is this? Where is the Pex?
Where do we find this pump???
In england uk we use check valves/one way valves to prevent hot water contaminating the cold drinking supply.... ????
The plumber would just take off the valves;)
Muricans carry bottled water in their semi/full truck, so they need not mind the quality of tap water. That would be like soooo 2016.
Closed boilers are just as bad as anything else. Also I would be surprised if it was the way you describe in the UK
The UK used to have hot water storage tanks up in attics and they were open to the atmosphere. They would often times become contaminated and too many people got sick. This is why you see separate hot and cold faucets throughout a lot of buildings in the UK.
In the US we have water heaters that are pressurized and completely sealed from the atmosphere. There is no risk of pathogens in the water to make you sick. However, hot water dissolves minerals, metals, scale, and other non harmful substances and can make the water taste different/bad.
Dušan Barlík I'm certain that you don't know anything about the US.
The pump kit has been replaced with TacoGenie 0011-CF-USK Pump with Under Sink Kit, 3/4" Shut-Off Flange, 1/8 HP at around $635.
This works under sink and is easy to install? I have a Chilipepper that stopped working in 3 years and thinking about replacing it with something better but this quite expensive vs $250.
TacoGenie 0011-CF-USK Pump with Under Sink Kit, 3/4" Shut-Off Flange, 1/8 HP
$980.88
Where I can find that pump?
where does the cold water go that has to Leave when pump brings in hot water without the faucets being turn on?
Anybody know what pump he use with internal low voltage relay?
it takes 22s for the pump to pump enough hot water and shut off
I get that the cold water from the hot line goes into the cold line, but isn't the cold line already full of water... does the pump just force that water out of the way? We are on a well with a pressure tank, would the excess water just be forced back into the tank?
No, because no water leaves your system before you open the faucet, so you're well motor won't turn on.
Good question, and one I'm asking as well.
Wondering if the home's booster pump will run more often due to any change in water pressure. Or, if the water lines are a semi-closed loop... is there no pressure change when water is NOT coming out of a spigot/faucet/shower/toilet/etc?!
so when you turn the hot water on, the heater will also turn on. This means that the heater is sucking in water from the cold pipes, thus there is going to be less water in the cold pipes becasue its being taken to the heater. The pump is filling in that void.
It's still a closed loop so the well pump shouldn't need to run. The booster pump creates a pressure difference which creates a localized loop where it draws water from the heater and pushes it backwards thru the cold water piping and thru the heater and back to the pump inlet. If the pump were too big it could conceivably drop the water pressure on your bladder tank and make your well pump come on faster than the pump outlet pressure could travel backwards, but it's take a big pump and a fucked is piping arrangement, so very unlikely. But if you start getting random and frequent reliefs blowing off on stuff then you know it's happening.
Rick Tomlinson ok now I know you're an idiot! No pressure? Lol then it won't move 🙄
Pump name and model please. Does it work with standard water tank? Thanks
So you have to manually turn on the pump and wait for it to shutdown every time before you want to use hot water? That's so "convenient" :)
How much would a plumber cost to install one of these ?
Where did the power outlet come from?
Where do I get that pump
Just to be clear...you won't have immediate access to your hot water because the cold water in the hot line is forced back into the cold line....and only when it detects the hot water reaching the location, it turns off and allows the hot to come through.
Is that how the pump works?
.
My question is actually based on pressure. Houses here are normally installed with an auto pressure pump for the main supply line. The pumps produces a pressure rating of around 10 bar equivalent to 145 psi (Pump on the pent house). Does this mean that the booster or pressure pump on the supply line will contradict the pressure and thus the flow with this recirculation pump?
I am not sure how this pump works but in the other video they say as soon as the water temperature at the valve drops to 98 degrees, it will allow water to be recirculated. By this, I believe the Watts small pump works on pressure stutus. When the valve shrinks due to heat change, water is allowed and therefore the pump detects the loss of pressure and starts to function. Does this means if the pressure on the cold supply line is greater or higher to some extent then the Watts pump won't start? In other words, what is the maximum pressure allowed on the cold line or the main supply line for this system to work properly?
I am asking this just because we are going to boost the supply line with a 10 bar/145 psi automatic pump for two reasons. 1. It's because we want pressure on all showers below as water supply is free fall from a tank above. 2. A 200 liter central heater is at the same level as on one of the showers. Pressure will be so less at this point.
Any help is much appreciated in advance.
Most places in the us you are either running off of a large well pump or city water pressure. We dont boost the pressure coming into the house, it's actually regulated down with a reducing valve in most cases.
Wow! I thought of a different way like installing a pipe to eject the cold hot water out of the hot water line outdoors through a garden hose to my favorite tree for watering so not to waste cold hot wter down the drain to my septic tank. Boom! you showed me how simple it is!! just shunt between hot and cold water line with a recirculation pump.. Bam my forehead for not thinking of that! my water heater is rather far from my shower and bathroom lavoratroy in my master bedroom bathroom like about 30 feet long! Oh, all my water lines are PEX type.. What do I do ?
arrrrghhh!
Does pushing this water back through the cold side cause potential long term damage? Reduce the life of the hot water tank? Is there a downside to this?
No
Can this be used if you are on city water? If so how would this affect a water bill?
I was just wondering if this would help or hurt a water bill.
I have a Mickey hacksaw, where do I get the Minny
Is this how it works? There is only one water source into the house that feeds both cold and hot sides and it can't flow backward to the street. So when the pump turns on it does 2 things, pulls from hot side and pushes to the cold side. The water heater would then pull in the water that comes from the pressure on the cold side. Would this be a way to prevent freezing pipes ?
I would think only if it's automatic and not on-demand, but I could be wrong. Ours at work is connected at the heater itself and no matter where in the building when you turn on the hot faucet, it's instantly hot, so those pipes have gotta be hot all the time.
In the UK we have what's call a secondary return
still leaves hose on hose bib for the winter
Correct me if I'm wrong, but will that pump not try to push that water also back into the network?
+TransfixedBunnies It will. It will create a circle of water through the water heater until the hot water triggers it to stop. It also makes the water heater heat up the water faster as the water being pumped back through the cold water line is getting warmer and warmer until the sensor shuts it off.
It pushes water into the cold side which goes through the house and then eventually it makes its way to the cold water inlet of the water heater.
Nomo Sapiens No, it would not push it into the water supply system. If your house supply was done right it should have a one way check valve to keep water from flowing from the house to the water supply, this would keep your pipes from being drained in a water supply failure causing your meter to meter air until the pipes are filled again when the water pressure came back...
Garrett Ducat k
Most municipalities have back flow preventers installed on their side of the meter
What's the brand and model of this pump? I like it has a remote control.
Love how he explains to her what she already knows.
I am with her. Where does the cold water go when being pumped? Won't the check valve stop it from traveling back to the cold water line?
Who said anything about a check valve? Life becomes a lot harder when you make up problems for no reason.
Since you added 120v outlet, why not to add a small tankless water heater? No wait, instant hot water until main unit starts delivering water to second floor. Right?
Because you would need one of those tankless heaters in every bathroom and the kitchen. And electrically heating water is much more expensive than a gas water heater.
Put how do you wire the button to the pump
Fantastic idea to save water. With the major droughts in California this should be mandatory for saving water or anywhere else there is water shortage issues.
We Fix Water Heaters Wise homeowners should invest in researching the many differences in the different types available on the market. Systems equipped with passive spring-based check valve (such as this one) prevent cold water from entering into the hot water side. But, what prevents water in the hot water pipes from siphoning into the cold water line when the water pressure in the cold water line drops during cold water usage events, i.e. flushing toilet, watering lawn, using cold water tap, etc? Nothing. Thermostatic valve controlled systems utilize comfort valves which "close after" 95F water reaches the valve. Any time less than 95F water is at the valve, the valve will be in it's "default normally open" position.
Having to wait for cold waste water down the drain as well. "Active flow control" rather than passive flow control is required to prevent water siphoning from hot water line to cold water line.
+Ready Temp Do you have any recommendation on thermostatic valve controlled systems?
Thermostatic valves actuate (open / close) in reaction to temperature. There are two types of thermostatic valve-based systems. One which utilizes a pump and one which does not.
The one which does not utilize a pump, relies on the power of convection for the water to circulate. Heat rises. This type system requires the valve to be located 2 or more stories higher then the heat source. Searching the internet confirms the same opinions I've heard from previous owners. Most stating that the circulation / flow occurred at a rate far too slow to be effective. The energy consumption / additional demand caused by water continuously entering the water heater out weighed the little, if any, benefit.
The second type of thermostatic valve system utilizes a pump at the water heater that must run continuously to maintain heated water at the thermostatic valve(s) installed under the sink(s). Again, here we have a near continuous flow of water (demand) entering the water heater. Searching the internet and speaking with a couple of new homeowners who had these in their home when they moved in conveyed that their frustration from wasting so much water having to wait for cold water and their +$200 monthly gas bills resulted in them unplugging the pumps power cord from the wall. But, the majority of complaints came from people tired of having to replace the black plastic thermostatic / comfort valves every year or two at $65 each. What really surprised me were two owners who clearly emphasized (curse words) they were tired of getting scalded while showering, each time their valves failed without warning.
At some point I question the mindset of anyone who accepts having a normally open valve connecting your hot and cold water lines together. What most people don't comprehend is the cause and effect of having an 'open' valve between your hot and cold water lines. Consider the fact that anytime cold water in the home / on the property, is used, the water pressure (psi) drops throughout the "cold water" lines. Thereby, leaving the hot water lines with a higher psi which naturally results in water from the hot water line (water heater) being easily pushed through any open thermostatic valves and into the cold water line anytime a toilet is flushed, grass is watered, i.e. cold water is utilized.
In my eye's, thermostatic valve systems are comparable to buying a car that promises to get you to work quicker, but the dealer failed to mention that return trips from work will take considerably longer. While also choosing not to mention the slow drip from the gas tank that occurs when vehicle is not driven.
So your saying a HOT WATER LOBSTER won't work for someone on a single story?
To my definition of hot, nope.
Would you leave this pump on 24/7 or just when you know you need hit water?
Only when you need it. Heats the hot line to 95 degrees and shuts off.
So the pump just moves the cold water from the hot water pipe to the cold water pipe. Not even any dynamic pressure, only static so very little for the pump to do. Good idea.
InsideOfMyOwnMind pathetic is what it is.
Jonas The Movie How is it unhygenic if the water never leaves the system? You already shower with a mix of hot and cold.
Doesn’t the cold water pile already have cold water in it?
Actually it is dynamic because it's moving.
Why?
@Jonas The Movie
If I have metered water am I getting billed when it's circulating or does not pull water in from outside?