Water heater pressuer relief line is dripping water?

Question

I am a first time home buyer . I was going away for a period of time and  I turn the electric breaker off to the water heater 3 days later as  I am walking around the house to make sure everything is fine I noticed a 2 pipes sided by side coming from the side of the house and pointing to the ground . One of them was dripping water. Its been dripping water for 3 days now almost 5 gallon every 6 hours When I asked about this I was told that is the water heater pressuer relief line . Is this suppose to do this because I turn the electricity off.   Please help

chris · Accepted Answer

The biggest thing that nobody realizes is that when you turn off a water heater the water cools and contracts causing the system to take on more water. When you turn it back on it heats and expands causing higher than normal pressure in the system which opens the relief valve. Most times the valve will not close perfectly because of calcium or other particles built up on the valve seat.
Replace the valve and the next time open a sink valve to relieve the pressure during startup.

MARK · Answer

Jonah, The "Temperature control" on the gas valve, that is on the front of the water heater is probably set too high. It should NOT be set on "High". Sometimes if it is, the pressure in the tank can become too great & water can leak out of the relief valve. The Temperature control on the gas valve should be set on the "Normal" setting. If you reduce that setting, that should take care of it. Otherwise, the pressure relief valve may have gone bad too, But, do the other thing, first! OK? Good luck!

Anonymous · Answer

You most probably have a worn water pressure valve. Your system is a pressurised type, and to maintain the pressure, the water pressure valve prevents any loss of water from the system. Over a period of time, the pressure sprin inside the valve loses its strength, or some grit or dirt in the water prevents the valve from seating correctly and water in the system can leak out. As it is a sealed unit, it cannot be repaired and it has to be replaced with the same type of valve and one that is set to the right pressure.

ralph b · Answer

could just be a bit of foreign matter not allowing it to close completely. in this case,turn the valve on & off a couple of times for short bursts.if this does not correct the problem, the valve needs to be replaced.

gas man · Answer

replace the press/temp relief valve or wait till the h20 in the tank has reached set temp and it may stop as the parts have expanded and sealed off the h20

Will · Answer

Either the seal in the valve has gone bad or the water heater's thermostat is stuck in the on position. My guess would be the thermostat. You need a multimeter to test it.

Water heater pressuer relief line is dripping water?

6 Answers