When the hot water is run at any of the faucets,ex; kithcen, bathrooms, laundry room, showers, bathtubs , a loud rumbling noise is heard coming from the furnace, through out the house. When two fucets are running water at the same time the noise is worse.
I've been told by that the problem may be a floating washer in one of the valves !

Hi Rumbbling...

What heats your hot water? A tankless coil at the boiler, an indirect coil with a storage tank, or a water heater? Let me know more, OK?

Mark

Thanks for replying. It's a tankless coil at the furnace.. Brand: Ever Hot, Meas. 12 inches wide x 16 inches high.
As I'm replying right now, the shower in one of the bathrooms is being used and the only noise I hear is of "water" running, no rumbbling !

Hello again, now the water in the "stand up " shower is now being used and the noise is back !

I also tried running the water in the bathroom sink of bathroom 1, no noise, but when I ran the water in bathroom 2 at the same time heard a lot of noise. The samething happens if any one faucet is running hot water and any other faucet is also running water at the sametime.

Any suggestions to the "rumbbling" sound?

Noises are some of the hardest things we work with here online and by your decription I can only guess that a washer has come loose at a shutoff associated with the hot water system and is causing the rumbling noise.

The big question then becomes, which shutoff? Here, I might eliminate or replace a couple shutoffs associated with the tankless coil and see if things improved.

Could also be the mixing valve/mixing valve element...

Could also be a number of other things, too.

Sorry I couldn't be more help here, but without hearing the noise itself I am at a loss at this point... *UGH*

Good luck!

Mark