The pressure release valve on the State Select Gas Hot water heater (40 or 50 gallon) is allowing water from the hot water tank to drip through the copper overflow pipe drain on the side of the house. There is no leak or drip around the valve or tank itself. The safety notice on the hot water tank says the pressure release valve is supposed to be tested once a year by owner. There are no instructions on how to test the valve. How does one test the pressure release valve?

The safety notice on the hot water tank says the pressure release valve is supposed to be tested once a year by owner. There are no instructions on how to test the valve. How does one test the pressure release valve?
To test the valve lift the handle slightly and hot water should discharge out of the overflow pipe.

The pressure release valve on the State Select Gas Hot water heater (40 or 50 gallon) is allowing water from the hot water tank to drip through the copper overflow pipe drain on the side of the house.
Do you have a backflow preventer installed near the meter. Have you got s sprinkler system. Is there a expansion tank installed on the cold water heater supply? Back to you. Tom

The hot water heater (State Select 40 or 50 gallon) tank allows a drop of water out the overlow pipe on the side of the house. Can it be repaired or does it need to replaced by a plumber?

The hot water heater (State Select 40 or 50 gallon) tank allows a drop of water out the overlow pipe on the side of the house. Can it be repaired or does it need to replaced by a plumber?
It would help if you would answer my question in my last post.

Do you have a backflow preventer installed near the meter. Have you got s sprinkler system. Is there a expansion tank installed on the cold water heater supply?
But to answer your question, if you have a faulty T & P valve that needs replacing just shut the power and water off to the heater and if the T&P valve's on the side drain the water down past it. If it's on topof the heater simply unscrew the copper discharge pipe and the threaded adapter from the valve so you can install it on the new valve. Teflon Tape all threads and reinstall. that's all there is to mit. Good luck, Tom

Don, you haven't answered all of Tom's questions and he pointed out to "To test the valve lift up on the handle slightly and hot water should discharge out of the overflow pipe.
" I'd give that atry and your pressure release valve may reset. If the valve continues to be a problem it should be replaced. Be sure to close the main and bleed off a few gallons from the tank via the drain spigot at the bottom. When installing the new valve use three full wraps of teflon tape on the valve.

Speedball:

Sometimes replacing the t&P valve isn't as easy as you described. The discharge pipe can be soldered in place. Removal is as Speedball suggests. Since in the post, it drains to the outside of the house, there is some plumbing involved.

How easy? Post a picture.

I want to find out why it's leaking in the first place before we get into replacing it. I'm still waiting for a answer to my questions. Regards, Tom

Speedball:

Sometimes replacing the t&P valve isn't as easy as you described. The discharge pipe can be soldered in place. Removal is as Speedball suggests. Since in the post, it drains to the outside of the house, there is some plumbing involved.

A leaking T&P can be symptomatic of far more serious problems, particularly if it's happening in a closed system -- And by "closed system" I mean a system with a check valve, heat trap nipples in the inlet and outlet of the H/W Tank or backflow preventer that isolates the system from the Utility.

Pressure build up from thermal expansion usually bounces back to the Source/Utility in systems without the above mentioned devices, but it has nowhere to go if one or all of the above devices are installed, with nowhere to go, thermal expansion will seek the path of least resistance, IOW, the T&P valve.

If the problem isn't dealt with by installing an expansion tank, or replacing a defective one, the T&P will weaken to the point where it just pops off.