Sirrus mixer shower new cartridge required or boiler service?

[Connor Williams]

Hello guys, I have a Sirrus shower which is a single lever thermostatic shower.

The water will not mix at all, it is either red hot or completely cold whichever way you turn the lever you get only one or the other.
Before I renew the cartridge & thermostat inside should I have the boiler checked, I have a Worcester greenstar combi which has no temperature dial to lower the hot water temperature.

According to the handbook the water temperature should be fixed at 55 c but the water seems very hot.

Should a thermostatic cartridge compensate this and allow more cold water through? At the moment the water is not mixing at all!

Many thanks for any tips,
all the best,
Connor

 

[PlumbBobBob]

yes a thermostatic cartridge should compensate for fluctuations in water temperature

 

[AJM P&H]

The cartride is scaled up. The boiler you're right has no hot water control as it runs on a "hot or not" basis. Cartridges are generally around the £60 mark as long as the shower isnt too old