Water Heater Pressure Relief Valve

[Rich Franklin]

We have installed a new dual gas/electric water heater. Both sources work the heater, but if we leave either source switched on for more than an hour or so, scalding water starts being ejected from what appears to be a pressure relief valve.

I presume it's a thermostat issue, but is there only one thermostat for both power sources? If so, what's the job like to change it?

Rich

[The Newell]

water heaters do put out very hot water, and do not have adjustable thermostats. Many times when the T&P valve is leaking, it's because you have lost the air pocket in the water heater tank If The hot water heater tank has lost the head of air this is your first fix. The procedure for doing this is:

Turn off the water pump, open the drain valve and drain the tank be sure the water has cooled before attempting this.

Close the drain valve.

Open a hot water faucet

Re-fill the hot water tank, either from city water or, as in my case, by turning the water pump back on

Turn off the hot water faucet when the tank has filled.

Next you can manually operate the relief valve. If re-heating the water results in the relief valve ejecting a continuous stream of water.

It's time to buy a new relief valve.