I live in a building built about 1950, I am trying to remove the Hot water valve stem in the shower to replace the washer. I CAN'T BREAK IT LOOSE.I have applied enough torque to feel the manifold behind the wall start to twist and it wont budge. the cold side is the same. I cant break the manifold or the seat because i'm on the top floor and also don't want to remove the wall, or flood below.
Please help me, oh knowlagable one

May be best to replace the valve with a modern thermostatic mixing valve if you have access to the back?

they make a large trim plate that will cover the three holes.

No access, I just need to break the stems loose. Any thoughts?

a picture MIGHT help.

sometimes a couple of shark raps to the middle of the wrench with a medium size hammer while applying force to the end will break it loose. (sometimes ???)

Be sure the stem is in the open (on) position when you try to remove it.

D you own the apartment or renting it? Do you have individual water shutoffs to the place? Make sure you have a wrench that fits the stem tightly and give it a few "raps" or hits to break it loose... kinda like an impact wrench does

I own the unit. I am afraid of breaking it or the manifold or the pipes.
yes I have my own shut off water knobs.
the plumbing is from early 1950's.
I'm going to try to attach a picture.

I cant post a picture.
and yes the socket tool fits well , no wiggle at all...

And it is both hot and cold that wont budge...
I did try with valve both in open, closed and half way...
thank you for the help,
Please give me a solution that wont cause me to have to break the wall open because I broke something. I cant afford that now.

when a fitting will not loosen there are 3 approaches
1)......... for the religious.... pray
2)........for the non-religious.. cuss and swear
3)....... for all others..... apply more force..
i'm joking..
an impact wrench might jar it loose.
an 18V inpact wrench that we use for putting in screws would be my choice.

thanks , I already have done 1 and 2 alot. I know with more force something will happen.
I keep thinking about how un-skilled the maintenance guys are here and since its both hot and cold that wont budge. I'm thinking they might have put some thread sealer in there and am worried about breaking everything behind the wall. maybe I will just have them do the work this way when they break it I can have them replace everything???
don't know what to do at this point. at least i watch a youtube video before I think I know everything...

Don't you know anyone with a cell phone that can take a photo to upload to PhotoBucket. You can then obtain a URL or link so you can post the photo on the site. It is always better as you know " A picture is worth...."

Direction of loosening in counter clockwise direction ????
Seems like a valid question.
If you have a good snug fitting wrench you can use a cheater pipe.
Torque is a good thing until mechanical failure enters the picture.