You need one of these. It will keep the water hot at a distant tap. It also cuts down on wasted energy heating water that eventually just get cold anyway. Insulating the hot water supply line to the bathroom will help too.
Yep, and in the showers. I'm not sure what happened with the plumbing in this house, but we used to have to turn the shower on full hot, wait 4-5 minutes, then get the temperature right and get in. It took forever and was a huge waste of water. A hot water re-circulation pump and hooked up some automation. No more waiting for hot water anywhere.
If you have access to the pipes behind the bath you could add the bypass valve and a recirculating pump. That's what I did to my bathroom and it's awesome. I put the pump on a smart outlet and tell google to turn on the hot water a few minutes before taking a bath or shower and it's been a hand changer. We no longer run the water for 2-3 minutes just to get hot water. It was super easy to install. I put the bypass valve under the bathroom sink because it was a lot less work then to add it to the bathtub pipes. The sink is only a few feet from the tub. If you have individual pipes running to the sink and run it won't work for you, but my sink and tub are connected to the same hot water pipe from the basement.
This is what I installed.
Your sink and shower have water-saving flow limits (usually under 3gpm). It can take a long time for them to pass enough water to clear the the pipes of the room temperature water (that cooled standing in the pipes between uses) so you start getting hot water from the heater.
There are a three solutions.
The easiest thing is to turn on the tub hot and let it run until hot. That will bring the hot water from the tank, and your sink and shower will be warm within a few seconds.
You can install a shunt that lets cold water in the hot water pipe go into the cold line, and put a pump at the hotwater heater. The drawback is these make your cold water side run tepid (from the warm water you've dumped into the cold pipe) for a few minutes. When the tepid water flushes out your pipes and the cold arrives, your shower is going to go COLD until you readjust the temperature. (My wife hated ours so much I had to take it out.) (LINK)
You can install a separate return hot line and install a recirculating pump. This is what hotels with large industrial water heaters have. You continually circulate hot water through the main pipe so when someone turns on a faucet anywhere along the line they get hot water fast. These consume more energy, because the water in the pipes is continually cooling, so you have to reheat it. Also, running the pipe can be a major expense and hassle because the pipes are are in the walls.
Here is what I installed: https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG/ref=sr_1_2?keywords=water+recirculating+pump&qid=1669768961&sprefix=water+rec%2Caps%2C181&sr=8-2
I have mine set to run every half hour or so. You could probably do less. For me this is also the master bath that I use, so it is nice to have instant hot water.
It installs on the hot side and the main purpose of it is to help with hot water getting to the far end of the pipe system. But as it does cycle some warm water through the cold pipe system, it works for preventing frozen pipes too. The way it works is there is a valve that you re-route your lines to. Then it cycles hot water up the hot water pipes and the valve closes once water gets to a certain temp. So in operation it cycles water through the lines and also the valve closes once water gets to a 'hot' temp so to speak. So warm water ends up cycling back through cold water supply.
My first thought would be a point of use water heater, the little five gallon guys but I don't know of an efficient way to power it DC.
There is almost certainly one made for motor homes and RVs running 12v or 24v. You might want to call a local RV dealer and ask them if they know of such a thing. The cost of building what you want may very well exceed simply buying one already suited to your needs.
These recirculators are very quiet and don't run very fast making them efficient. They can be found for much less money, this is a higher end model.
I have one of these: https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
Basically uses the cold water line as a temporary hot water recirculation line. If you wanted to improve on it you could make it smart instead of just a dumb time clock on the pump.
Before I installed this thing, I would run the cooled-off hot water into the tank on my toilet using the handheld shower nozzle.
You don't need to be "ultra rich" to have instant, very warm water. I have the product linked below and if you install the accompanying valve at the faucet farthest from the hot water heater, every sink between the water heater and the valve will enjoy the benefit of the recirculation system. In California where drought is a real problem, this device is saving me perhaps 15-30 seconds of wait-time per person (4 in my household) per day. The water isn't instantly hot, but it is instantly warm enough to immediately start showering.
I was in your shoes earlier this year. I had a natural gas water heater in the garage and an electric heater at the opposite end of the house. I decided to go hybrid electric in the garage and completely remove the other one. I had to go under the house and run the hot water supply to the end of the house where the other water heater was located and also install a hot water recirculating pump https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG/ref=sr_1_5?crid=1XHMWS0673C33&keywords=Watts+hot+water+recirculating&qid=1663447718&s=hi&sprefix=watts+hot+water+recirculating+%2Ctools%2C165&sr=1-... but I am super happy with this setup and we have significant energy savings monthly.
Watts Premier Instant Hot Water Recirculating Pump System with Built-In Timer 6" X 6"
This is going to be cheaper than replacing the entire heater, but also keep in mind you'll be losing heat by keeping hot water in the pipes.
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG/
It looks like a connection for a hot water circulation pump. Something like this: https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
When the pump runs it send hot water down the cold line to get the hot to the tap faster. It's a work around that requires less pluming. Usually the under sink connection is made on the fixture that is located farthest from the water heater.
I don't know any that detects temperature in the way that you had in mind. But this should do what you want: https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
Keep in mind, recirculators are a huge waste of energy if you're trying to maintain constant hot water at all times. Once water leaves the tank, it immediately cools. Half the length of your furthest faucet will need to be replaced with hot water. Assume you have a 50 gallon tank and it's 1 gallon of water that is replaced. That's 2% of the hot water tank that's "lost" because you wanted instant hot water. This in turn means your hot water tank will run more often than needed, thus decreasing the life of the tank.
The button option helps save water and can give you "instant hot water" if you plan ahead. Press the button before you start using the toilet. Press the button before you start getting undressed for a shower. If you need to wash your hands right away, then you'll have to suffer through some cold water.
LPT: Install a recirculating pump at your water heater and then the sensor valve at the farthest sink from your water heater. Water will get up to temp much faster afterwards.
As an alternative to those, I use one of these: https://www.amazon.com/dp/B000E78XHG/ref=cm_sw_r_cp_apa_fabc_HP3N2XZPC4H3V3924WVB?_encoding=UTF8&psc=1
It circulates the hot water through the system and is very effective at keeping the pipes from freezing. I added a temperature controlled relay that only turns on when the temp outside is low enough to warrant it. This was a great option for lines buried in walls I did not want to open up.
Most likely frozen pipes.
I have 170year old home. If you can rerun them, that would be best. If you can't look into getting a recirculating pump.
It's what I use. Put the "sensor" at the farthest point in your water system. It will keep hot water at the taps, and drop warm water back down the cold.
It's saved me from frozen pipes.
a recirculation pump will solve this problem and is a very quick and easy installation. this is the one i have
it installs on top of your water heater, lines should just screw together, and it circulates water to keep hot water at the tap. It has an analog timer so you can set it to run only during times you need it, but I just plugged mine into a smart plug and used my home automation to control it
You could insulate it but my recommendation would be to get a hot water recirculating pump. They’re about $200 but it keeps hot water at every tap in your house.
Watts Premier Instant Hot Water Recirculating Pump System with Built-In Timer https://www.amazon.com/dp/B000E78XHG/ref=cm_sw_r_cp_api_glc_fabc_bevZFbG45ZKN3
I just bought a hot water recirculation pumpfor about 175.00 on Amazon. Got it and installed it yesterday. It's an intermediate level install but if you read the directions and have proper tools, you can install it just fine. Anyway, I also have the pump connected to a smart outlet which I can turn on with my phone whenever I want hot water at the tap without running the water. Let it run for about 5 minutes before you use, or set it on a schedule. It's so worth it!
That is the complicated swanky way to do it, but I'm not that fancy. ;)
The recirculation pump I got has a hot water valve to stick under a sink. This way the cold supply line becomes your return line. The valve is open until the water gets hot, then it closes so you don't end up with hot water in the cold line. It's not perfect - you'll get a bit of warmish water in the cold line especially at the sink you have the valve on, but that's never been a problem for us.
You need some sort of pump, such as this recirculating pump.
You might be able to get away with something like a pond pump, depending on how high up the roof is compared to the supply tank. But you'd need some sort of external timing mechanism so you're not pumping cold water into the tank a night and in the morning. Possibly something Pi-based so you can tie it to a couple of thermometers?
I was looking into one of these but am not convinced of it's effectiveness. I am also worried about the cost involved with continuously reheating the circulating water.
Thanks. How does the tank figure out how much cold water to mix in there to get the correct temperature? The temperature setting is all the way at the bottom of the tank.
For the pump, would something like this work? https://www.amazon.com/Watts-500800-Recirculating-System-Built-/dp/B000E78XHG/ref=sr_1_1?ie=UTF8&qid=1475431166&sr=8-1&keywords=recirculating+hot+water+pump
It's worth it.
You could but this would be way easier and cheaper.
I had frozen pipes the first year in this house. after we thawed them out, I wrapped every cold water pipe i could get to with a pool noodle, added insulation to the wall where they entered from the street and installed a hot water recirculating pump. No problems still a decade later , including the -20c temps of 2019
https://www.amazon.com/Watts-500800-Recirculating-System-Built-/dp/B000E78XHG/ref=as_li_ss_tl
​
whole thing cost me a days work and about $400, highly recommended
my bad. My kitchen is far from my hot water heater, so i used to have to run the water for a while to get hot water. I got one of these and use a generic smart switch.
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
Now can just say " turn on hot water" and set an automation so that it turns off after 15 mins.
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
​
You're welcome :)
You don’t need a separate recirculating line, you can send your “cold” hot water back into your cold water line.
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
Install a hot water pump circulator.
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
They make pretty much this. It pushes cooled water in your hot water line into your cold water line.
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
I have had one of these for a few years. Absolutely love it.
Watts Premier Instant Hot Water Recirculating Pump System with Built-In Timer 6" X 6" https://www.amazon.com/dp/B000E78XHG/ref=cm_sw_r_cp_api_glt_i_CVDYZE31XSKT9ANHGSZF
https://www.amazon.com/gp/product/B000E78XHG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Only have had it for a year, but we have had zero issues. Reduced hot water time from a few minutes to 15 seconds. Yes, the tap water at the bathroom sink is warm when you first go for cold water, but it cools down pretty quickly.
Install is very easy, took me 1/2 hour, needed two fittings which cost about $20.
Item | Current | Lowest | Reviews |
---|---|---|---|
Watts Premier Instant Hot Water Recirculating Pum… | $166.14 | $166.14 | 4.5/5.0 |
^Item Info | Bot Info | Trigger
They already do, it's called a ShowerMi$er It's mainly for the RV crowd so you aren't wasting fresh water, it recirculates into your fresh tank but the same thing can be done at home. Or just get a water recirc valve put into your home so hot water is constantly circulating so you don't have to wait the minutes it takes for hot water to get from your tank to your shower.
This is what I installed. I put it in according to the instructions. https://www.amazon.com/dp/B000E78XHG/ref=cm_sw_r_cp_api_glt_fabc_AMG96Y9962A25J8343S7?_encoding=UTF8&psc=1
Oh. Cool. I think I can do that with mine. I have this one:
Watts Premier Instant Hot Water Recirculating Pump System with Built-In Timer https://www.amazon.com/dp/B000E78XHG/ref=cm_sw_r_cp_api_glt_fabc_X8BA7VHRVJ794WVARREK
I have a Watts hot water recirculating system. It easy to install as long as there is an outlet available near your water heater where you install the pump. It works by recirculating hot water from your hot water pipes into your cold water pipes. At the sinks at the end of the plumbing run, usually the sinks farthest away from your water heater, a temperature sensor valve is installed under the sink connected to the hot and cold water lines. When the hot water side falls below a certain temperature the valve opens and allows the water to flow from the hot side into the cold side. When the hot water side comes up to temperature, the valve closes and stops the flow of water to the cold side.
From you description it sounds like you will need at least two bypass valves, one for the bathroom downstairs and one for upstairs. Just buy the base model at first and see if it fits your needs and if it doesn't, buy the sensor valve kits for the other sinks that still needs it.
One drawback of the system is that instead of waiting for hot water you'll be waiting for cold water. It's a minor thing and the wait for it isn't as long as the wait for hot and is totally worth it. On the other hand if you live in a climate where freezing pipes is a concern this will help protect you from that. I have soft water so I haven't had this problem but if your water is hard, minerals can build up in the sensor valve and stop it from working properly. To fix it you remove the sensor valve and soak it in CLR or the like and then rinse thoroughly and reinstall. The installation is pretty easy and there are plenty of guides that will take you through it.
I personally think this is the easiest way to improve your quality of life in a house and is worth every penny. Congratulations on your new home and from now on youtube is going to be your friend for fixing the problems in your home and hopefully save you some money.
Good luck.
Actually 1/2” pipe is an advantage, it holds 1/2 the water volume per foot than 3/4 and a 1/4 of the water volume per foot than 1”. Source Flow rate doesn’t change appreciably, however with larger pipes there is much more cold water that must be displaced before hot water arrives.
Less costly than the full hot water loops systems are the single pipe recirculating systems. They work using a valve that uses the cold pipe as a return. They have there pros and cons tho, I installed the system because our kitchen sink was a full 2 minutes to hot water. Works great but wastes energy. Also the special thermostatic valve is crappy, worked great for 6 months but developed hard water deposits that cause it not to close which has the side effect of making the cold water side hot. Solved that with some home automation magic to turn the pump off instead. So we waste less water and waste less time waiting, but waste more energy heating water that cools in the pipe.
We Americans have Amazon which has things like this:
https://www.amazon.com/Watts-500800-Instant-Recirculating-Install/dp/B000E78XHG
I installed it in two of my houses. Took about 15 minutes per.
Also available rebranded as Watts for some reason... https://amazon.com/Watts-500800-Recirculating-System-Built/dp/B000E78XHG
I'm going to advise against this completely because it's not going to work, unless I'm completely misunderstanding what you wrote.
The water needs to be constantly circulating or it's going to get cold. If it only circulates for x time after someone opens a tap, they're still going to have to wait for the new hot water to get to the faucet.. and then the extra circulation will continue after they shut off the water.. which is just wasting energy since nobody is actually using the water.
It will be: open tap - wait for cold water to get hot - shut off tap after getting hot water - hot water fills the domestic hot lines, and then cools off because nobody is using it anymore.. and that seems to defeat the purpose completely?
You either need a small pump that is constantly circulating the water or, probably the best bet, is buying a small insta-hot for whatever location you want hot water. If you want it everywhere.. then try: something like this? http://www.amazon.com/Watts-500800-Recirculating-System-Built-In/dp/B000E78XHG
I have no experience designing systems for residential, but I make a living designing plumbing for industrial/commercial/superconductor/hospitals, etc.. so I don't know jack about who makes decent quality systems for the home.
Maybe some kind of hot water circulation system, so you always have hot water when you turn the faucet on. Most of them seem a lot more complicated than that though. http://www.amazon.com/Watts-500800-Recirculating-System-Built-In/dp/B000E78XHG