HW Heater Pressure Relief Valve- relieving

[lee polowczuk]

I have a gas hot water heater in my basement.

I have been in the house for two years. The hot water heater is probably 5-7 years old.

In the past three months or so, the pressure relief valve has released water 4 times.

Recently, I turned the temperature down a bit, but it just took another dump the other day.

There were no other problems with it the first couple of years.

I have city water.

Hot water in the house seems fine. 3 of us share two bathrooms. We probably use 7k gallons a month.

The pressure relieve valve is screwed into the top of the heater with copper running across and then down to within a couple of inches of the floor.

Any thoughts?

[cwhyu2]

PRV gone bad t&p bad do you have an expansion tank on your w/h?

[lee polowczuk]

PRV gone bad t&p bad do you have an expansion tank on your w/h?

There is no expansion tank. I don't think i have ever owned a house with a WH expansion tank.

The tag says 100xl extension 4 on the PRV...

looks like it just screws in.

[cwhyu2]

Your PRV mayby malfunctioning,you need yo check your incoming water pressure.Try to find a pressure gauge to attach to a hose faucet laundry tray.

[Gary Swart]

If you have a PRV, first make sure it is functioning. Buy a cheap pressure gauge that you can connect into the system. Any water system with a PRV should also have an expansion tank, and here's why. When water heats, it expands and must go somewhere. If a system does NOT have a PRV it is referred to as an "open system". In an opens system, this expansion is absorbed by the city water main, so no big deal. A system with a PRV is referred to as a "closed system" , This is because the PRV acts as a check valve and prevents this expansion from going past it. This causes the pressure in the water heater to rise very rapidly and quite high. One this pressure reaches the limit of the TP valve, it trips to protect the tank. In other words, it does its job. An expansion tank gives the expanding water a temporary home. Some newer water meters also have a check valve built into them to prevent the possibility of contamination getting into the city system. Try this test with the gauge. Connect it to a hot water faucet and turn the faucet on. Then open another hot water faucet to drain out some water from the heater so that it will begin heating. Watch the gauge as the water heats. It will probably scare the hell out of you!

[lee polowczuk]

the prv is functioning.. I can pull the handle up..and water will come out of the copper tube....