No hot water

[DinghySailor]

Today I replaced the potable freshwater pump because at some point in our 4 months in the boat yard, the 16 year-old Sureflo stopped pumping. Now with new pump installed, the cold water line pressurizes and delivers good flow, but the pump does not come on when the hot valve is opened on either of the two fixtures aboard. Our 6gal Raritan water heater is plumbed with basic Qest fittings and lines (no accumulator tank, no manifold), backflow restrictor installed. When the hot line is opened, I hear gurgling in the water heater, indicating water in the tank and release of air in the line, but the pump does not switch on. Any idea what could be keeping the pump from pressurizing the hot water line?

 

[Davidasailor26]

My guess is some kind of blockage in the hot side of the line. I’d start by disconnecting the input side of the back flow preventer and turning on the pump to confirm you’re getting water that far. Then reinstall the preventer and see if water gets passed it. That would be the most likely place to clog. If water is getting that far then keep opening fittings further down the line to isolate the problem.

 

[jviss]

My guess is that the backflow preventer is in there backwards.

 

[Scott T-Bird]

David has the right approach. If you hear gurgling sounds in the tank, that means the tank isn't getting water. The line is under pressure in front of the tank, which means the pump isn't going to be triggered when you open the faucet. You have a blockage in the supply feed between the cold water manifold ahead of the tank and the tank. The preventer is the most likely culprit, unless you have a valve closed on either side of it.

 

[DinghySailor]

Thanks all. Jviss, you nailed it. When testing the line for leaks I removed the check valve to inspect it and then reinstalled it backwards. I’ll refrain from the self abuse and just say lesson learned.