Removing Water Heater Relief Valve

[mont1340]

We have an older fifth wheel (1981 Komfort) and I need to replace the water heater relief valve. Twenty-nine years of use and it's pretty well frozen in place. Anyone have any suggestions for getting it out without busting something? Will heat work? Any tricks or thoughts would be greatly appreciated.

[tworootless]

Spray some nut loosening lubricant (BP Blaster) on the thread area. Get a wrench on the head and give it a GENTLE TAP to the right (Tightening) If it moves at all, then I'd try backing it out.

[ralper]

If you can heat what it is screwed into without burning up the rig that will help too. Do not heat the relief valve just what it is screwed into.

[Gary RVRoamer]

The valve already gets pretty hot when the tank is operating, so you would have to really heat it up to help much.

The tank on an Atwood heater is aluminum - pretty soft. Good luck!

[RVhauler]

If the HWH relief valve is that old then I am surprised that the tank hasn't started leaking and my belief is that IF you do get the old relief valve off that it will not be long before you will have to replace the whole unit. At this stage of the game I would replace the HWH with a new more efficent unit. Just my 2 cents from experience.

[RV Wizard]

You might try letting the penetrating oil do it stuff while you let the tank cool off (turn it off and run hot water out). Get the relief valve cold. You might even put a baggie of ice on it. Turn on the heater to get the tank hot and try removing the valve before the valve gets a chance to get hot. It should come out but not easily at first.

[swailes]

Heat the area around where the two pieces thread together, acytelen may be needed once the area is glowing hot spray only the valve with cold water (trigger sprayer will work best. this causes the valve to shring while cooled an may break the pipe threads free of each other. You may also want to leave a tap open to relive any pressure that may build.
good luck