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Bob M. Bob M. is offline
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Default Water heater noise

"LouB" wrote in message
Bob F wrote:
LouB wrote:
I happen to be standing near the electric hot water heater while the
dishwasher was running. Hear noise like "rattling". Something to
worry about or just normal? Ideas please?

It could just be the heat traps at the top of the heater. Some of them
rattle at low flows.

Thanks, I think:-)) What is a heat trap?


A short stub of pipe (on both hot & cold side, usually) with a metal ball in
them. Designed to keep hot water in when there's no hot water being called
for, they sometimes rattle. I've never been real impressed with this

I made a heat trap out of 1/2" copper pipe; it is basically just a loop and
has no moving parts, no flapper valves, etc. so it will always work,