Noise coming from water heater

[cmawendy]

When turning on the hot water there is a noise coming from the water heater. It only makes the noise when the hot water is on not the cold....has anyone had this problem? It is like a buzzing noise. It goes off as soon as you turn the water off.

[richfaa]

ours humms and crackles..

[JimF]

That is is non return valve on the outflow side of the HW heater. I think pretty much all of them do that. Ours did until I took the check valve out of it. I got tired of the noise. Might not be the right thing to do but we have not noticed any difference and now have better hot water flow.

[IAMontana]

Jim by taking the check valve you may not be able to winterize you plumbing with out getting a lot of antifreeze in to the water heater.

[snfexpress]

The check valve is eaasily replaced on most models.

[precisiongizmo]

I had a similar problem with my 2006 3500RL hot water heater in that hot water just stopped flowing. By taking the tube off the outlet fitting I was able to shove the backflow valve back into the fitting and get water flow again. I figured this would be a temporary fix and am happy to learn the that unit is replacable. I may do as Jim did (replacing the check valve with a straight thru fitting) and get more water flow. Thanks for the knowledge folks.