Mysterious 3 second sounding/running of peripheral pump

[Naureen]

Hello All,

Pump brand and model is,
Stuart Turner Monsoon U2.0 Bar Twin
Part no. 46480 ROI

Pump sounds/runs for a few seconds (randomly) even if shower not running.

Yes, there is a trouble shooting guide in the manual, but random bursts of activity from the pump is not specifically mentioned.

Yes, the pump seems to very adequately perform its duties when hot taps and hot/cold shower is in use. But it ‘mysteriously’ runs for approx three seconds ‘randomly’ approx 4 times in a 24hour day.

Please consider advising me if this is something a non-plumber individual such as myself could probably fix or whether I should escalate to plumber.

 

[Harry Bloomfield]

My guess, based on caravan water pumps which use pressure drop to trigger them on....

Water contracts as it cools in the pipes, pressure reduces, so the pump runs briefly to restore that pressure.

 

[Naureen]

Thanks Harry! Appreciated. I agree that could be what is occurring. It is still a bit mysterious in my view, given there was hardly a murmur out of the pump for the 9months that led up to December 2020. Thanks again. Open to hearing from you and our fellow forum participants.

 

[Harry Bloomfield]

Pump in caravan is inaudible and if it runs out of water, the pumps runs continuously. So I know when that happens, to avoid wrecking the pump, I have an alarm on it. As the water in the pipe cools it would run for a few seconds, waking us up during the night, so I simply turned the pump off.

Might that be a solution, turning it off? Or perhaps rubber mounting it, so it cannot be heard when it runs?

 

[Gasguru]

First check is that the pressure vessel on top of the pump has sufficient charge...see the manual.

 

[oldbuffer]

Issue can be caused by an airlock in the hot or cold water system, not necessarily in the pipework directly connected to the pump.