Fault / No hot water with Bristan Shower

[kennym]

Hello All

I have a Bristan mixer shower. Pressure is excellent and I have replaced all seals on the Thermostatic cartridge. The CD valve is turning easily and 'looks' as if it is ok.

Unfortunately the temperature dial does not make any meaningful difference in the temperature which is tepid. The only way I can get the shower to be warm, is to turn on the bathroom sink tap to full - this reduces the pressure significantly but means the shower is war but not hot.

I have attached pics of the shower and cylinder. Any ideas what might be wrong and how to fix? Any help much appreciated!

Ken

 

[DripsnDropsBognor]

Cartridge needs replacing completely?
Have you tried manually adjusting the set temperature with an Allen key?
Blocked filters at the inlets (if filters fitted)?
Failed check valve possibly normally built in on the inlets.
Failing that call a plumber