Thermostatic Shower System - Can’t change temp. Very hot water only.

[kablack929]

The house we moved into had this system. Now we can only get hot water and can’t change the temperature. I’m thinking the cartridge might be bad. Does anyone know the replacement I need? I can’t find a brand/part/model number anywhere.
Thanks!

 

[Geofd]

Can you show the trim?????

 

[kablack929]

Can you show the trim?????

I think this is what you’re looking for?

 

[Geofd]

I've never seen that, try soaking it (the stem) in vinegar for a little while then re install,you may also want to spray, the components in that 1st picture

 

[kablack929]

I've never seen that, try soaking it (the stem) in vinegar for a little while then re install,you may also want to spray, the components in that 1st picture

Unfortunately this didn’t work. I did this and re-installed. Turned on cold water only and it came through just fine. As soon as I turned hot water back on, all that came out was hot water. It seems I might be looking for a replacement.

 

[Geofd]

Next step I would do is bring your pictures and the stem to a plumbing supply hose and see if they can identify