This question is regarding Sirrus 1850/968 Thermostatic Cartridge without Thermostat - SK1850-2

Shower pump cutting in and out

Hi, We have a problem with our shower pump cutting in and out and the pressure dropping right off. Even when it is running there is very little power. Do you think it could be a problem with this cartridge not opening the valve fully - or is it more likely a problem with the pump/water pressure? The shower has been installed for many years. The cartridge was replaced some years ago, but we do live in a hard water area. I'm not sure how best to fault find the most likely cause of the problem. Thanks, Andy
Asked 7 years ago by Andrew
We will need to know the make etc of the pump.

You can test the performance of the pump by redirecting the output into a bucket etc to test it.
This will tell you if it is a pump or shower problem.

Answered 7 years ago by Barrie Seabright

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