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 water recirculating problem
Author: t-bird (CA)

I have a Grundfos hot water recirculating pump mounted on the hot water outlet on my electric water heater and a return line connected to the bottom of the tank with a check valve. The water heater is 2 years old and both elements are good. My problem is after showering for about 2 minutes the water gets cold. I removed the pump and closed the return line and now I get hot water in the shower. I took the cover off the pump and when I plugged it i n it worked. There wasn't any indication of buildup. Can anyone help me?

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 Re: water recirculating problem
Author: bernabeu (SC)

inspect / replace the check


"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Edited 1 times.

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 Re: water recirculating problem
Author: packy (MA)

yeah... the check valve (one way valve) may be a stand alone valve installed in the loop or it may be integral to the pump ?

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 Re: water recirculating problem
Author: Curly (CA)

OP states that his pump is located on hot outlet side of heater....isn't the pump in the wrong spot ?

His pump should be located as per Bern's drawing ?

I've only seen pumps on hot outlet side when you did NOT have a dedicated return line.

If you have the Grundfos Comfort System, pump on hot side at heater and manifold mounted under sink farthest away etc. and no dedicated return line.


You guys have a lot more experience with pumps than I do, so I just asking.


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