Comments on: How To Replace The Drain Valve On A Water Heater?

By: mike b

mike b — Sat, 05 Sep 2009 14:29:14 +0000

That is not cement on the threads it is pipe dope (sealant) it is supposed to make unscrewing the valve easier.
If this tank is older you might not want to remove the valve. Due to corrosion it could break off.
You can get a thread adapter and screw a new valve on the old one. Unless of course the old valve will not open. These valves use hose thread. Any hardware store will have an adapter.
If you choose to remove the valve you will need a big pipe wrench or a cheater bar. Do it on a weekday just in case you need to buy a new water heater.

By: frozen

frozen — Sat, 05 Sep 2009 10:15:09 +0000

Try a little WD-40 on the rust and let it soak in. Then put a pipe wrench on the drain valve and put as much pressure on the end of the wrench as you can. Then have a second person hit the handle of the wrench repeatedly with a hammer. The hammer shock should break up the rust and loosen the drain pipe threads without damaging the tank threads.
OK so it is cemented. Try the same thing without the WD. What you need to do is break the cement bond with the hammer. The hammer will give a high impact which will hopefully break the brittle cement. Unfortunately if this does not work then you will probably have to leave it alone or replace the tank.

By: JJ

JJ — Sat, 05 Sep 2009 03:15:40 +0000

Best advice is to leave it alone. If the tank is over 6-7 yrs. old the corrosion is on the inside as well. This is not unusual especially if there are lots of minerals in your water. If you break that valve off, odds are you’ll end up buying a new tank.