Remover collar to access shower thermostatic cartridge

[Alexb9882]

Hi there, my shower runs hot then cold then hot then cold... To prevent i keep my combi boiler on low hot water temp setting. Tested all other taps etc and they're stable (can be consistently very hot if needed).

Suspect thermostatic temp cartridge knackered in shower.

Want to replace but cant access it - there's a stainless steel collar I can't get off (tried d'escaling it, mole grips...etc). Happy to damage it as it wont be visible (sits behind face plate).

Any ideas?

Will add pics

 

[Timmy D]

With the condition that collar is in, I’d get the recip saw or multitool out and cut it off.

 

[king of pipes]

You've done damage there bud valve looks in bad nick I'd consider changing it you will struggle getting it apart

 

[Alexb9882]

Thanks both!

Valve is knackered and wanted to replace.

Agree about cutting it off. Tried allsorts to get it off and bent it etc. It's not needed as will be hidden so no problem. Can get away with not having it.