water tank noise

[Sacramento Dave]

I just found this group. Most likely an old subject, but with a twist. Are gas water heater is starting to make a strange noise. It is not the common popping sound. It is like a 1/2 second drum roll about every 10 seconds, you would almost think there was a animal in the wall scratching itself in the wall. The tank is 7 years old GE 50 gal. It also has a 12 year warranty on it, I can just imagine how far I would get with that. Any suggestion? I haven't tried draining it yet. Thanks.

[CES]

Dave, this is caused by mineral deposits on the bottom of the tank. The deposits insulate the steel, the steel gets hot enough to cause that rumbly bubbly noise.

I've made out real well with Reem warranties, but I'm not sure if deposit conditions are covered, can't speak for GE WH warranties.

Good luck with it.

~C~

[Sacramento Dave]

Found the noise , It was not that mineral deposit sound witch I am familiar with. The insurance Co ( home warranty) sent out a plumber. He spent about an hour trying things and determined it was excessive water pressure, but he left had no gauge to check it. But being in the pipe trades as soon as he left I set up a gauge I check the Pressure Regulating valve on water supply. 60 PSI with water running, slowly went to 83 PSI with thermal expansion. Tank has a Max working of 150 PSI Noise was still there at 60 PSI, So I ruled out excessive pressure. Plumber said that the Dielectric nipples going into the tank had check valves. I had a set of dielectric nipples without check valve. So that solved the problem not a noise to be heard. There is a small marble in the check valve. I am also going to pipe an expansion tank on the hot side 83 PSI I think is a little high even though I've had no other problems. In my home warranty deposits condition are covered, Someone would get a check for writing that in a warranty.

[Blackbeard]

Why not just install a pressure reducing valve on the main to the whole house like required by code in many areas? Wouldn't that be easier that installing an expansion tank? expansion tanks aren't designed to reduce pressure. A PRV is designed to reduce pressure.

[Sacramento Dave]

the expansion tank is to help with thermal expansion not to control pressure.The PRV will control the pressure of the water when it is running, on the house side the pressure will slowly rise because of thermal expansion caused by the hot water expanding. As we all known water dose not compress but will expand with heat so it dose not take much to raise the pressure. Most hot water system I have piped in commercial system have an expansion tank. Some have a PRV that will blow of excessive pressure but then you have to pipe a drain line off of that, Not practical in a home.

[Ned Flanders]

You placement of the thermal expansion tank on the hot supply is incorrect. It belongs on the cold inlet to your water heater, with a check valve behind it. How does pressure make a check valve rattle???? Do you have a hot water recirc line?

All water systems have expansion tanks.

[Blackbeard]

Well yeah...water doesn't compress. But since you have an expansion tank on the cold side already, if you're talking pressure, you need a pressure reducing valve.

You were talking about installing an expansion tank on the hot side of the system IN ADDITION to the expansion tank on the cold side. You don't need two expansion tanks.

[Ned Flanders]

dave i am waiting for you to say something that makes just a little bit of sense.

but more importantly; the tank does not go there for reasons that will effect your domestic water supply adversely.

another asshole lib who thinks he is soo much smarter than us plumbers, and we could not possibly understand his problem cause its "special". I belive you are in the pipe trades. I belive you trade bongs too. CA sucks.

[Red Jacket]

Reem must be one hell of a good Co. I was watching some home remodeling show and they pulled out a perfectly good 20 gal. Reem. It was the first model they ever made ! What....50 some years old ?

[Red Jacket]

You need a expansion tank if there is a one way valve on the water main. Your HWT PV will keep blowing without one.