I had a leaking (plastic) drain valve on my GE hot water heater. It was leaking from the inside of the valve. The small rubber washer was crimped.

I installed a new brass drain valve that I purchased from home depot using teflon tape. The valve now leaks from the threads of the tank/valve. I removed it again and used plumbers puddy and it still leaks. I tried to tighten the valve more to stop the leak without success. I even tried a second brass drain valve without success.

I do not see any obvious deformation or rust on the tank threads. I also have not stripped the threads or crossed them at all.

Here are my questions:

What could be the problem? Does the tank only accept plastic drain valves? How tight can I tighten the valve onto the tank? The local hardware store suggested a last resort epoxy on the threads of the new drain valve; but, that would be a permanent install.

Your suggestions would be greatly appreciated.

Does the tank only accept plastic drain valves?No! The threads should accept all boiler drains,

How tight can I tighten the valve onto the tank? As tight as it will go with the boiler drain in position and looking down.

The local hardware store suggested a last resort epoxy on the threads of the new drain valve; but, that would be a permanent install. If it's between that and replacing the tank what choice do you have? My opinion is that you cross threaded the connection. Wrap 3 o 5 rounds of Teflon Tape and coat it with Epoxy, Good luck. Tom

I agree with Tom. Do a few extra wraps of teflon and maybe even coat it with a little pipe dope (rector seal) on top of the tape, and tighten it up until you just can't tighten it any more. Plumbers putty is not to be use for this type of connection, so if you did really use plumbers putty, that would explain part of the problem.