Anyone use a water recirculator - any experience?

[zoro]

After a big waterbill a few years ago I went on a water saving jihad - low flow showers, coke bottle in toilets etc. The thing that still wastes water for us,  is running the shower to get warm water, and with Teenage girls it adds up still. Plus with low flow showers it also now takes ages to waste the same amount of water.

I have been looking at these hot water recirculating pumps that cost about $200, but give you instant hot water  - so save a lot of water. The back of the envelope calculation seems to work out with about a 5 year payback, I have had to make a lot of assumptions that I'm not sure about i.e. how long water is run and how many times a day - but I wondered if any of you actually put one in and have real life experience / data on if it is a good thing or not.

Thanks in advance.

[YttriumNitrate]

In your five year payback period, relative to the water savings, how much was the cost to run the pump and extra fuel for the water heater due to heat losses from the pipes?

Edit: Did a quick search and found this article blasting water recirculators. The numbers in the article are a bit suspect, but they could be off by a lot and reciculators would still be a bad investment.

Should You Get A Hot Water Recirculation Pump? The pump will cost you $200 to install, $5.50-$32 to operate, will waste $160-$400 per year and will save you $4-$50 on your water bill.

https://www.treehugger.com/ask-pablo-will-a-water-saving-hot-water-recirculation-pump-really-save-me-money-4858682

My guess is that if you actually want to save money, your best bet would be to install something like this:
https://marey.com/product/mini-marey-110v-marey110/

[trygeek]

This is the one that I have  https://amzn.to/2XCeAlr at Amazon I didn't know it cost that much as it came with the house. I like it because it has been problem free and the hot water comes out as soon as you turn it on. I also like the fact that it has a timer, so I set it up to come on in the morning and evening when everyone is showering and it's off the rest of the day.

[MudPuppy]

I think the old fashioned 5 gallon bucket for collection and use that water for plants, flushing toilets, etc  might be your better bet.

[Cadman]

Depending on how much access you have to run new plumbing, and the location of your water heater in regards to the fixtures, this might work for you: https://www.buellinspections.com/re-circulating-hot-water/

[Taran Wanderer]

We have a recirc pump and a timer, and I also have it set for morning and evenings only. The bathrooms are on the opposite end of the house from the water heater, but the kitchen and laundry are close, so this works quite well. Still, as noted above, I suspect we’re spending more on heating water that has cooled in the lines than we’re saving. Plus, water here is cheap, and sewer is free (septic). But it’s convenient. Mid-day showers take forever to warm up.

[cool7hand]

Just posting to help me follow. Thanks for the tips!

[ericrugiero]

An on demand water heater at the shower makes more sense so you aren't constantly losing heat from the pipes.  You can buy the on demand heaters sized for the whole house (which wouldn't fix your problem) or in smaller sizes for point of use.  Because they are located at the point of use you don't have to run all the cold water through the pipes before getting hot water.  If you did multiple point of use heaters and got rid of your hot water tank you could save money on electric (because you aren't reheating the tank full of hot water all the time) and water (because you don't run cold water so long to heat it up).  The one YttriumNitrate posted would work but they also make some that are mounted close to the shower (not on the spout) and aren't as noticeable.  Depending how your hot water pipes are routed you may be able to install one heater on the hot water supply to that bathroom and have just the short run to the shower and sink to wait to heat up.  You do need access to the plumbing and an electric supply for each heater. 

Edit:  As I understand them, a water recirculator would save you water but cost more in electric.  It would be convenient (instant hot water) but I'm not sure that's a good tradeoff either financially or environmentally. 

[protostache]

The previous owners of our new house put in a recirculated pump. Initially we kept it running all the time, but now I have it on a timer and a thermostat, so it comes on only during the day (we're all at home all the time right now) and then only when the return line is within a certain threshold. This has dropped our energy usage on the hot water heater by about 30% (it has it's own electric meter wired in, so I've been able to track it).

If you decide to get one, I strongly recommend you buy one with those capabilities built in. I also strenuously recommend insulating the heck out of the hot and return lines, which will keep the heat in the pipes instead of heating up your floors. Ours aren't insulated very well and it's a bit of a project for me to get into the crawl space and do it.

As far as if it's worth it, I would approach it as a comfort thing vs something that will save you money. Instant hot water is a luxury, but we're willing to pay for it vs waiting several minutes for hot water to make it's way to our master shower or kitchen sink.

[NorCal]

We have one in our house.  I put it on a timer, but the heat differential of the water actually keeps water recirculating all day.

While it is nice to have hot-water on demand, our hot water heater runs WAY more than it would otherwise.  I wish the timer would actually stop the flow.

My back of the envelope calculation is that this thing costs us $10-$20/month in higher gas bills (CO).  It certainly won't save you money. 

[Radagast]

As a no-research response, I think this makes no sense. You would be adding a new mechanical part (pump) and maybe a new pipe. The idea is that the pump would run whenever the water in the house dropped below a certain temperature. You will lose money for electricity to run the pump, and for electricity/gas to keeping the water hot, in exchange for a small savings in water. plus all the issues with pump maintenance. It is probably not a good idea, unless you are planning it to be part of a radiant heat system, which is what it effectively is. This is a luxury adding system, not a money saving system.

[norajean]

Our house came with these and I unplugged them. We have to wait maybe 30 seconds for hot water in the shower. I hated listening to water gurgling in the pipes 24/7. I was also concerned about what impact constant circulation could have on erosion rates in the pipes. Last thing we need is a pinhole water leak in the wall.

[Dicey]

We do. Our water heater is in the garage and the kitchen and M. Bath are at opposite ends of the house, roughly equidistant from the WH. Using a timer was a pain in the ass, so we use google home minis to turn it on and off as needed. Works great.

[NorCal]

One additional consideration is the existing plumbing in your house. A recirculator requires your hot water lines to form a loop back to your hot water heater.

This may be no big deal, or it may require re-plumbing a significant part of your house. You’ll have to talk to a plumber to find out.

[MudPuppy]

I know this isn’t exactly the issue you described, OP, but I ran across this today and thought I’d share for anyone interested

https://www.showerstart.com/

It stops your shower when it gets warm

[Fishindude]

We are fortunate to live in an area where water costs nothing more than the electricity to run the well.
I'm curious about where you live and what kind of monthly household bills are you experiencing to be so concerned about a couple extra gallons of water usage?

[skiersailor]

I bought a relatively new house with a hot water recirculating pump already installed and have unplugged it.  It did keep the hot water taps hot, but it also caused the cold water taps to run slightly warm which wasn't an acceptable tradeoff.  I suspect that somewhere in the system the hot water and cold water lines are too close together and heat is being transferred between them.  So even if your plumbing is built for a recirculating system, you might not like the result.  And if you don't insulate your hot water lines all the way to the taps you are wasting energy.