Hot water recirculating

[Kungur]

I want to install a small recirc pump on my hot water line to service my far off bath. I will put a return line in. Question when I bring it back to the water heater I would tie it into the cold water supply. Do I need a check valve at this point?
I also want to install a switch that would only run the pump as needed. Say for 60-90 seconds. Anyone know of a source for something like this? Thanks

[ralphtheplumber]

Yes, you need a check valve, and also an expansion tank if you don't have one already.

Normally these pumps are wired into both a timer and an aquastat. That's a little thermostat that clips onto the return line and allows the pump to run until you start getting hot water back.

Grundfos (& others) sell a little circulator pump that comes with the timer and aquastat built in.

[plumbdog10]

I agree with Ralph on the check valve question.

But......if you want a switch that controls the recirc. pump for 60 to 90 seconds, why have a recirc system at all?

Of course it is possible, wire your pump to a switch, turn it on when you like. You can get the same effect by turning the hot water on on your shower.

[PLUMBER JAY]

what is the purpose of the expansion tank in this application.

If your far off washroom is in the upstairs you maybe able just to put a return in and have the water naturally recirc itself. As the hot water cools it falls back down to the hwt. I have heard of people doing this but i don't know how well it works. But you would have nothing to lose in trying this as if it didn't work you could then put a pump in. all pipes must have fall back to the tank.

[PLUMBER RICK]

what is the purpose of the expansion tank in this application.

If your far off washroom is in the upstairs you maybe able just to put a return in and have the water naturally recirc itself. As the hot water cools it falls back down to the hwt. I have heard of people doing this but i don't know how well it works. But you would have nothing to lose in trying this as if it didn't work you could then put a pump in. all pipes must have fall back to the tank.

a buddy of mine does this on 90% of his repipes and it works great. no pump, no power, no wear and tear, no problem:)

rick

[toolaholic]

I've had good sucess with the Grundfos home comfort pump and manifold
around $300 no new piping install in about 1 hr Tool

[PLUMBER JAY]

tool
I am not aware of what you are suggesting him to do?

[toolaholic]

have this in my own home. check out their site pump and timer screw on top of heater , manifold plumbs under furtherst vanity. no additional plumbing! nice for slab homes