Noise In Water Heater

Not the mixer valve in my case, as I had that replaced for other issues last summer. Once re-installed my "issues" were resolved, but I still had the noise. I regret not having the hot out check valve replaced during the same service call, as I still have the "noise."

Thanks for the information!

We use to have that problem on our old rig. Many rigs have a mixer valve. It too builds up with calcium and starts to moan, squeal, so to speak. You might notice a decrease in water pressure too. It mixes the hot and cold water ( thru hot water line). It allows the hot water tank to heat hotter and not burn you by mixing with cold as you turn on a faucet.

Three times we replaced this in just over 5 years. Note item below might not be for your rig

https://www.amazon.com/Atwood-90029-Mixing-Valve-Heater/dp/B00HTN4PXE

YEP^^^^^

Bad valve as in Check Valve in Water Heater Tank HOT Out

Scale/calcium build up and valve chatters
Cheap plastic plunger/spring/o-ring assembly
Usually when they start chattering they eventually fail...plunger gets stuck, o-ring get dislodged, valve body gets plugged....then it's all quiet cause NO hot water flows out

Bad valve is right but I let ours just make the noise and it quit after a couple of years.

Bad valve had the same problem this year