This question is regarding Ultra Infinity A389 3-way Diverter Cartridge and Handle (Chrome) - SINFC

Cannot regulate the temperature of the water on my shower

I fitted a cartridge replacement A389 3 way diverter from you in Feb 2017,no problem with that,I have a problem now with regulating the temp at the other end of the bar.When I press the knob in to turn the temp down it seems to be heating the water up more.,can you Identify my problem please
Asked 5 years ago by Malcolm
If you are on a combi boiler.

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 you are not on a combi strip our the temperature cartridge and check that the filters are clear.

If they are OK then you probably need a new Temperature cartridge, when you have the temperature cartridge out take a couple of photos just in case we need them to help ID the cartridge.

Answered 5 years ago by George Thomson

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