Shower pump won't stop

[VictorDelta]

We've had a shower powered by a Salamander CT50 twin pump for 3 years and it's worked perfectly.

Out of the blue the other evening, the pump motor started all by itself and would not stop without being switched off. There's nothing loose on the pump and no sign of any water leaks. I've also given it a few small knocks in case one of the pressure switches was jammed - but to no avail.

By switching the pump on and off manually I've had a perfectly normal shower today so it is working ok.

Will I have to replace the pump or is there anything else that might be causing the problem? Any other suggestions?

 

[CombustionGuy]

Sounds like a stuck switch or faulty switch inside the pump

 

[VictorDelta]

What would you suggest to unstick it?

(Presumably it would be more likely to be a stuck switch if the shower had been in use at the time and then wouldn't switch off afterwards. In this case, the pump just started running out of the blue [the shower was not being used at the time])

 

[newbuildinstaller]

ring salamander pumpwise, they are very good, tell them the problems, if it can be fixed they will advise (it may still be in warranty) if not new pump time

 

[VictorDelta]

I've now spoken to Salamander and they agree it is either a flow switch or circuit board problem. However, if the latter, they need me to work out which side is faulty or whether both are (twin pump).

The tech support chap I spoke to rattled off how to do this but could not supply any written instructions or point me at a relevant website. I've tried googling in case I could find something suitable say on youtube etc but drawn a blank.

Can anyone help by telling me what I need to do? I'm not a plumber but am pretty good at sorting simple technical problems.

Thanks.