This question is regarding Mira Excel/Select Thermostatic Cartridge - 903.33

Mira Excel Cartridge

I ordered the above from your company got cartridge installed . The shower has very little power and the water goes hot then cold then hot again can you advise please plumber suggests its a faulty cartridge ????
Asked 9 years ago by Helen

Regarding the temperature fluctuation or cool running, it could be a faulty cartridge. However to check this if you have the shower fed from a combi boiler, see if you can get hold of the hot supply pipe before it enters the shower or perhaps as it leaves the boiler.


If when holding this pipe the temperature fluctuates or goes cool, then the problem is not with the shower but more likely with the boiler, as the shower can only deliver what the boiler sends to it. 

Disregard the temperature at the taps as they have a different flow rate.

If your system is a gravity fed one then please contact our sales team about a replacement.

Answered 9 years ago by Anonymous

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