How to replace thermostat cartridge

[zack6600]

Hi Folks, Need your advice on how to access a thermostat cartridge to fix/replace. Please see pics below. I have manged to to get the main shower control cartridge out as it is leaking badly. But now need to sort the thermostat/mixer out now as very stiff and difficult to turn to cold. The problem is I can't work out how to get the chrome surround off, which I am assuming I need to do to access it. It is the bottom one in third picture. Could anyone please advise?

 

[Timmy D]

What were they originally designed for, I wonder.

I’ve got some Sheffield originals passed down from my grandfather.

 

[Ric2013]

Tbh, I might remove my footies, can’t remember the last time I used them....

I bought the wera joker self setting spanner, I thought if it could do both 15mm and 22mm compression nuts, it would be handy in tight spaces.

I emailed them to confirm the jaw could fit 22mm, they confirmed.

Bought it, some 22mm nuts don’t fit and its a pain in the bum to use.

Very disappointed, love all my other wera tools. Complete waste of money. Used it once and never again.

Perhaps they thought the nut dimension was 22mm?

 

[king of pipes]

Ric had the advice needed the cartridge is held in with a grub screws in the valve body . Kop

 

[Deleted member 120897]

Ric had the advice needed the cartridge is held in with a grub screws in the valve body . Kop

Yeah, had already taken that out. I just can't get it to shift. Most annoying

🤷🏻‍♂️