"David" wrote in message
ups.com...

Thanks for all the quick advice, everyone. I was going by the manual
for the heater (GH Wood Series Pro model JW525, which appears to have
an 8-year warranty), which suggests that periodic opening of the T&P
valve is normal.

It is not normal for it to do so by itself. It should be tested manually
once or twice a year, and that is probably what the manual meant.

There is something wrong, and it needs attention now. When water heaters
explode, they make quite a mess.


The pressure could be a problem. I had a PEX joint start to leak
about a year ago, and the plumber (who didn't have a pressure gauge)
turned down the pressure regulator at the main shutoff (it was wide
open). Perhaps it needs to be turned down even further.


You can get such a meter at the local hardware store for $10. Normal is
50-80 psi.