When I turn off the water to the house (for vacation) and open a faucet to relieve the pressure, I notice that the hot water recirculating pump makes a lot of noise that it doesn't when the water is on. Do I need to unplug the recirculating pump to prevent damage while the house water is off?

If I do unplug the pump, can it be damaged if not woking for too long?

Thanks for any input.

4 Answers 4


Running the pump dry for an extended period can damage it. You should unplug it rather than let it run dry.

If it sits idle for longer than a couple weeks for vacation, minerals in the water could cause it to stick when put back in service. It usually just means you have to disassemble the pump and free the impeller before it will work again.

Good luck!


Do I need to unplug the recirculating pump to prevent damage while the house water is off?


If I do unplug the pump, can it be damaged if not working for too long?



Yes & maybe. Yes, unplug it or unless you actually need power for something (minimal heating, alarm system, phantom lighting, etc), turn off the whole place with the Main Circuit Breaker.

And maybe, there's a literally miniscule chance of some sitting minerals in the water to ever so slightly surface corrode something. But, with closest &/or a 2nd tap open so the pump can dry out as quickly as possible it shouldn't be anything noticeable when the water goes back on. Any evidence would likely show up in your faucet aerator(s).


I say yes... I was gone for a few days and turned off my water main. Leaky toilets (I think) relieved cold water pressure, which relieved hot water return line pressure, which relieved hot water pressure coming out of the tank and (somehow) stirred up sediment. (The tank may not have been flushed in awhile as I bought the house recently.) The sediment apparently gummed up the pump as the water would heat up, but only some faucets, and only after running for quite some time. Turning the pump off/on had no effect, pump was totally silent and apparently inoperable.

I turned off the pump, flushed the water heater, and refilled from cold water supply. Turned the pump back on. It's running, but now with a grinding noise that I surmise to be impeller damage from sediment (though at least it's running now). Now that the tank has heated up, it seems everything is working again, except for the impeller noise/damage.

So... Unless you have flushed your water heater recently and/or you know your cold water circulation is water tight, seems safest to turn off the pump if you are going to turn off the main. Unless you want to spend a whole day Google'ing about hot water recirculation pumps and flushing sediment from your hot water lines, cleaning faucet aerators, etc. :)

Not the answer you're looking for? Browse other questions tagged or ask your own question.