Water Heater Pressure Relief Valve
Shakedown trip this past weekend. Great trip, but discovered a small drip coming from my water heater relief valve when the water heater is turned on. Not a serious leak, just a drip. It was conver...
Forum Discussion
Couple of things going on......
When water is heated it 'swells'. That is what 'air pocket' in top of WH tank is for......allows for the water to swell without a large increase in pressure. Water can not be compressed (air can) so without air pocket pressure increases enough to cause T&P Relief valve to 'weep'
Air pocket is normally established just by filling WH but can be lost over time.
Reestablish air pocket by turning water supply off, open faucet hotside to relieve pressure, open T&P Relief valve via lever and then let it snap close when water stops running out, close faucet, turn on water supply.
Over time T&P Relief valve seat will build up deposits especially when allowed to weep. As deposits build up more weeping, ore deposits etc.
Can be cleared by opening T&P Relief valve with water supply on and allowing water to blow thru valve then letting valve snap close. Repeating several times.
And then......
Sometimes due to age, amount of deposits etc. it's just better to replace T&P Relief valve. When doing so it can be easier to remove exhaust duct work so accessing valve is easier.
When water is heated it 'swells'. That is what 'air pocket' in top of WH tank is for......allows for the water to swell without a large increase in pressure. Water can not be compressed (air can) so without air pocket pressure increases enough to cause T&P Relief valve to 'weep'
Air pocket is normally established just by filling WH but can be lost over time.
Reestablish air pocket by turning water supply off, open faucet hotside to relieve pressure, open T&P Relief valve via lever and then let it snap close when water stops running out, close faucet, turn on water supply.
Over time T&P Relief valve seat will build up deposits especially when allowed to weep. As deposits build up more weeping, ore deposits etc.
Can be cleared by opening T&P Relief valve with water supply on and allowing water to blow thru valve then letting valve snap close. Repeating several times.
And then......
Sometimes due to age, amount of deposits etc. it's just better to replace T&P Relief valve. When doing so it can be easier to remove exhaust duct work so accessing valve is easier.
