Water line noise/ air?

You might try emptying the tank and then refilling. Are you hooked up to city water or well water? If well water, after you empty the tank put some bleach into the tank and let sit for a few hours, drain, refill and drain one more time to flush out the tank. I don't know if this will help but worth a try.

Do you hear the noise only when your running hot water. Do you hear the noise when you're not running hot water. And what kind of noise is it making.

DutchmenSport wrote:
Do you hear the noise only when your running hot water. Do you hear the noise when you're not running hot water. And what kind of noise is it making.

Only the hot side. No noise when running only cold side. City water hook up. Tried adjust PSI, didn't change it.

Hard to describe noise. I'll see if I can record it.

Here is a video of the sound.

Hot Water noise.

Any time you hear noise at water heater when running hot water it most likely is the check valve in hot out chattering.
They are just a plastic plunger, spring, o-ring assembly (cheap junk).



As for that 'air'
You should have an 'air pocket' (by design) to control pressure increase.
Water swells when heated and w/o air pocket pressure can increase enough to cause T&P Relief Valve to weep

Turn off water
Open faucet to relieve pressure---leave open
Open T&P until water stops flowing---then let it SNAP shut
Close faucet
Turn on water supply
Air Pocket established

Thanks, that was what I did. Now for the check valve. I'll see how easy that is to access.

Thanks.

Looking at the tank, the check valve must be inside the tank? All the connections are just normal outside of tank.

Google RV check valve - they look just std metal plumbing fixture but have plastic device inside which might be making the noise. Mine connects directly to the outlet side of the hot water tank.

Thanks Kevin. I'll check it out.

If it's a Suburban W/H it the check valve for sure just like Old Biscuit said. He's one sharp cookie on this stuff. If it's a Atwood and not a XT model it will have the CV also. If it is a XT model, it's located in the mixing valve (the MV has issues, but not normally check valve problems). CV is usually near the bottom of the tank. Simply screws into the tank. Easy replacement. Some folk take the valve out and use it without that CV. If you do, when you winterize the system, antifreeze get in the W/H even when you bypass the W/H. Just sayin' rockin'