no hot water w/recirc pump off

We had a recirculating pump installed in our new house to provide instant hot water in the master bathroom and the kitchen. We keep it on a timer, shutting it off at night. The other night I ran the bath in the master bath and after 20 minutes, all I got was tepid water. Same in the kitchen. Another bathroom, not on the recirculation pump, had plenty of hot water. Should I be able to get hot water in the master bathroom and kitchen when the recirc pump is off?
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You should, but it seems like the cold water is back-feeding through the pump when it's off. Is there a check valve to prevent cold-water backflow?
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Good question - I'll ask the plumber who says there is nothing wrong.

pump
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Margie Davis wrote:

If you told your plumber what you told us, and he said, "There is nothing wrong.", then you better find a new plumber.
Jeff

--
Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"My luck is so bad that if I bought a cemetery, people would stop dying."
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