Pressure Relief Valve
Posted by Steve on April 11, 19100 at 10:25:10:
I have an older water heater that recently had both elements and thermostats replaced. After this repair, the pressure relief valve began releasing water on a regular basis. Now, it starts an almost constant whine or whistle as soon as it heats up and continues until the valve is manually released or until the water is run for a while. The temperatures on the thermostats were set at about 140 when the plumber left, but I have lowered them to about 120 in an effort to get rid of the problem. I'm a little concerned that this problem did not manifest itself until the day after the plumber left.

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