A common problem with a seized gate valve on 22mm hot water pipe. It won't move and I don't want to shear the stem. Rather than replace the fitting [which is difficult] I thought I may be able to leave the valve body in place and remove the valve stem by undoing the bonnet [it moves ok] and replace it with an identical unit. The gate valve is ~ 30y old marked BS 515[4?], stamped PN20 with the maker's initial, C&P inside a triangle on the body of the valve. I'm looking for an identical replacement please.
Any advice as to the wisdom of what I'm doing and getting the identical replacement would be much appreciated.