removing an old boiler drain valve

rreale

i would like to remove and replace 2 boiler drain valves that are installed in an oatey washing machine outlet box. They are 27 years old and dont shut off too well. they are connected to copper. can i use put a wrench on them and unthread them . i am a little worried about damaging the pipe behind the wall

HVACNUT

There's no removable frame on the box to get a wrench underneath?

I wouldn't chance it without a counter wrench. Could be tephlon only. Could be Leak Lock. Could be Perma Tex. Could be soldered.

Big Ed_4

Yeah I would be too , Two wrenches are needed to prevent twisting the piping . Looks like the locking nut is missing on the supply nipple . See if you can pull up to grab the nipple . If not it will be safer to replace the box …

EdTheHeaterMan

Do you need to replace the entire valve, or just the washer and seat?

rreale

i put a small hole in the drywall, it is soldered. I'll try to get the stem out and replace the washer.

hot_rod

Often times the seat in the valve is nicked or damaged, I don't think that valve has a replaceable seat, so a grinder like this may be needed.

Or sometimes a tapered faucet washer will work, it seals inside the seat a bit.