On Feb 7, 9:02*pm, wrote:
On Sat, 07 Feb 2009 12:42:10 GMT, Chuck wrote:
Rick-Meister wrote:
A pressure relief valve at the main water valve is left over from the
days when they were not required on water heaters. As the water heater
heated the water and it expanded it would pop the relief valve rather
than blow up the house plumbing.

These days water heater manufacturers must install relief valves right
on the heater. Plus, many communities require an expansion tank near
the WH to absorb the expansion.

Some cities also required a one-way check valve to prevent the
expansion from forcing your water back into the city's water supply.
That prevents your house from contaminating the entire community if
something goes wrong at your place.

You have two choices depending on what your city requires these days.
You can either remove the valve and cap off the opening. Or you can
replace the valve with a new one. Of course, that assumes that you
already have a relief valve on the water heater.

Not talking about the prv on the water heater. That is working ok. This prv is
in line as water pipe enters the house. CB

I'd venture to guess this is an older house and that PRV is now
superfluous.- Hide quoted text -

- Show quoted text -

Not if it is also a Pressure REDUCING Valve. If the city system
pressure is much over 60psi then I would replace it with a modern one
(and install a surge tank).

Sorta OT but the PRV drain on the water heater should be routed to a
safe drain.

Harry K