Hot water would not turn off, really could use advice!

[NishQuiche]

Our shower has a hot and cold setting.We live in an older house, built in about the 70's, so its an older shower...not sure if it makes a difference. The Hot setting on it wouldn't turn off, so we switched off the main water, and went about removing the plastic H then unscrewing the screw with a phillips, before removing the main handle. This is the part we were stuck at. We watched some instructional videos and it says the whole main metal part is supposed to twist off so you can work on the smaller pieces underneath...but ours simply WONT twist off! It looks like the people before us may have plastered it on, or it could be a calcium build up of some kind...anyone know how to remove the big metal ring part off? Is there a remover of some kind we need that would work?

The instructional videos also said that once we remove this we need to replace the washer, that probably eroded away, is this accurate? We absolutely can't afford a plumber right now, and Im hoping to have this fixed by this weekend because I need to go back to work Monday and its not practical to not have water all weekend...

 

[Terry]

A brand or a picture could help.

If it's a Delta shower valve, there is a dome or threaded end that holds it together. I sometimes put a torch on that to heat and expand that metal part, and then if threads off easier. Make sure you have water handy. You don't want to burn the house down with the water shutoff.