Pumpless Recirculation Loop for Domestic Hot Water?

pine grove coal user · Post by **pine grove coal user** » Sun. Jan. 03, 2016 7:52 pm

My boiler is at one end of the house, my kitchen is at the other. I am tired of wasting so much water waiting for hot water. But I don't want to have a pump running 24/7/365. Is it possible to install a recirculation loop for domestic hot water WITHOUT the use of a pump?

lsayre · Post by **lsayre** » Sun. Jan. 03, 2016 8:06 pm

pine grove coal user wrote:My boiler is at one end of the house, my kitchen is at the other. I am tired of wasting so much water waiting for hot water. But I don't want to have a pump running 24/7/365. Is it possible to install a recirculation loop for domestic hot water WITHOUT the use of a pump?

I have no idea how it could be done without electronics, but here are a few electronic options, one of which claims to cost as little as $2 per year to operate.

http://aquamotionhvac.com/hot-recirculation-systems/

Hambden Bob · Post by **Hambden Bob** » Sun. Jan. 03, 2016 8:20 pm

Nice Job,Larry ! This one had me thinking hard,but offhand,I couldn't come up with anything recirculating using ambient house system pressure. If You're on Well and Septic,these little gems sure look like they can help out. Another thought would also be to insulate Your hot water lines to minimize how long it takes to get useful hot water at the tap.

pine grove coal user · Post by **pine grove coal user** » Sun. Jan. 03, 2016 8:25 pm

Thanks. I looked at this. I don't understand how this could work without a return line. Does anyone have any experience with one of these? Do they work as advertised?

lsayre · Post by **lsayre** » Sun. Jan. 03, 2016 8:26 pm

pine grove coal user wrote:Thanks. I looked at this. I don't understand how this could work without a return line. Does anyone have any experience with one of these? Do they work as advertised?

Lower down they have return line options as well.

I suggest calling them. I can only speculate (OK, guess) that the no return line model dumps cold water into the drain as needed until the line is hot, then it shuts off, waits for the water to cool, and repeats. Sort of like the "rejection ratio" issue with an under the sink RO water purifying system, which rejects about 10 gallons of water (and dumps them down the drain) for every gallon of purified water that it generates.

Post by **franco b** » Sun. Jan. 03, 2016 8:26 pm

Run a small return line.

WNY · Post by **WNY** » Sun. Jan. 03, 2016 8:27 pm

you have a check/temp valve between the hot and cold at the furthest faucet, it recirculates from the hot side to the cold side. so the cold might be luke warm when your first turn it on if it just circulated, but should get cold rather quickly.

somthing like this

http://www.watts.com/pages/whatsnew/IHWRS.asp