Force 10 shower
 

My son is having problems with the shower in the house he has just
moved into. The shower is a "Force 10 Thermostatic" with a single
lever to control on/off and temperature, and is "Victorian" style
(i.e. brass and porcelain).

The problem is that the water temperature is virtually uncontrollable
and too hot for comfort. The water is heated by a combi boiler.

I have dismantled the valve and checked the thermostat capsule in a
bowl of hot water and it appears to operate OK.

I do not know if "Force 10" is the manufacturers name or a model/type
name. I cannot find any references to this name on the internet.

Has anybody come across this name before? Any ideas what to do next to
correct the problem?

TIA

Pete