Stuart Turner Monsoon pump sticking on or off

[dwinevs]

We have a Stuart Turner Monsoon 2 bar shower pump which has lately been either refusing to start, or not switching off when we turn off the shower. Tapping the side of the outlet pipe seems to unstick it more often than not, but it's a real nuisance. We have an oil-fired Aga, and the water does get very hot, and I wondered if this might have anything to do with the problem? Any ideas?

 

[exedon2]

Reed switch float sticking especialy in hard water areas. Have seen the sealing washer distort especially with hot water and cause float to stick.
Or Reed switch itself that's the part strapped to outlet.
This assumes its a positive head pump.

 

[Joandfran]

This behaviour is almost always due to the rubber washer which is fitted behind the magnet in the flow switch. They tend to expand or distort if the water temperature goes over 65 degrees, which it usually does if you have something like an Aga, or solar hot water heating. Annoyingly, Stuart Turner won't supply replacements for these - you have to buy a whole new flow switch assembly for about 40 quid, however you can buy heatproof silicone washers to replace them very cheaply on eBay, and they are a doddle to fit. I kept having the same problem, and replaced two pumps before trying these a couple of years ago, since when I have had no further problems.

Stuart Turner Monsoon pumps 2 x high temp silicone flow switch washers + O rings | eBay

Are you having problems with the flow switches sticking on your Stuart Turner Monsoon shower pump?. "This product has solved my problem with my Stuart Turner Monsoon 1.5 bar twin pump at a fraction of the cost of buying the service kit from Stuart Turner.

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