Water Heaters - Pressure Relief Valve Problem

I recently did my annual draining some water from my water heater and as usual I also tested the Pressure Relief Valve. I've done this every year, however, now water is still dripping out of the valve. I've tried it a couple of times, draining more water, turning the water supply off and also turning the gas off and still am getting about a 1/2 cup of water dripping per day. Do I have to replace the PRV and if so can I do it myself (I am handy with plumbing), however, the tag on it says that a licenced plummer has to do it.

Thanks,
Ron M

I have the same problem, only I'm getting about 2.5 gallons a day.
I replaced the valve myself. It's easy. All you need is 2 pipe wrenches, some pipe dope & a new valve. The valve cost me $28.00 at any plumbing supply. Copy the info from the metal tag on the valve, so you get the correct size & pressure rateing.
The usual size is "3/4 & usual 30psi.
Oh!
Make sure you turn the water supply line to the furnace off,prior to starting.

Hope this helps.
JackOfAll Hills

The 30 psi relief valve is for a low pressure boiler. A water heater generally uses a 150 psi & 210 degree relief valve.

The relief valve for a water heater is rated at 200º/150 PSI. The 30 PSI relief mentioned would run full open immediately.

The relief valve also must have a BTU rating equal to or greater than the BTU rating of the WH. Typically the heater would be in the 36,000 to 60,000 range, and the reliefs are rated 100,000 BTU.

There are 2 basic types: short shank and long shank. You need a long shank if it is mounted on the side of the heater. Short shank works on the top.