> Recirculate hot water-completed-pictures added

[time2roll]

I added a system to circulate hot water. Not really a convenience thing but to use my fair weather trailer in temperatures well below freezing.

I installed an El Sid recirculating pump. This pump is good for potable water and appears to be leak proof. Fairly low amp draw on 12 volts.

I used a Grundfos valve mounted under the bathroom sink for this purpose. These are made for home systems. The vale allows hot water to return through the cold water feed back to the water heater. Valve stops the flow as temperature approaches 95F. My hot and cold pipes run together so the heat should also transfer a bit.

Here is a diagram of my water system:
The freeze up was happening under the bunks area that is not accessible.



Here is the pump:



Grundfos valve mounted against the wall:





Pump is running:



Another angle that shows the hot water pipe connection.
Also shown is my GoPower 300 watt inverter if interested.



Has worked like a charm. Only issue is I prefer not to have the pump run continuous as it makes a bit of a low rumbling noise. So I have added a small 12v relay triggered by the furnace signal wire. The more the furnace runs the more the pump runs. And of course can't hear the pump with the furnace running.

And shame on photobucket for stopping the links in a previous thread.

[GordonThree]

gatorcq wrote:
I used a $65 rv water pump, plumbed under the farthest sink. Used a switch. When needed we turn it in for less then a minute.

Use similar in our house susan and i built in 2004. I wonder why more rver's have not done it, when there WH is placed in the farthest location from a sink/shower.

Nice job.

Less than a minute to keep your plumbing from freezing? How do you use it at night or when you're not in the RV?

[gatorcq]

I used a $65 rv water pump, plumbed under the farthest sink. Used a switch. When needed we turn it in for less then a minute.

Use similar in our house susan and i built in 2004. I wonder why more rver's have not done it, when there WH is placed in the farthest location from a sink/shower.

Nice job.

[Lynnmor]

I simply ran a return from under the bath sink to the water tank vent. The return has an on-off valve and a metering valve to adjust flow. With this setup, the existing pump does the work. Most of the plumbing and the fresh water tank are heated. There is also near instant hot water in the bath to conserve water.

[lawrosa]

Nice. As a plumber I can appreciate that..

That check valve is thermostatic... I believe 90f they open to circulate and close at an upper temp..

These I install to get instant hot water at the fixtures..

I was toying to do a hydronic heat set up like that with the water heater and a fan over coil. But the water heaters are too small... Not enough btu's..

Whats the amp draw on that pump?

Good job.

[profdant139]

Thanks a million for posting this -- I know it is a lot of work, but a lot of people will benefit from your innovation. Well done!

[ScottG]

Great job engineering a total fix!