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

Temp of water @ shower goes cold

While in shower Mira excel, blender, water initially hot then runs cold. Checked filters ok,hot side of valve hot when running but turns cold, when shower goes cold.
Asked 3 years ago by Chick Mcateer, Denny Falkirk
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.

Answered 3 years ago by Barrie Seabright

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