Domestic water pump keeps running, is that normal?

[Lambchopper]

My mum's house has poor water pressure, so she has a water pump fitted to boost the pressure when having showers. As far as I'm aware, it just comes on when there is a demand (i.e. Taps on, shower on etc.)

Earlier today, I popped round to water her plants while she was out. I filled the watering can as usual, then went out and watered plants for a couple of minutes. When I came back in, I noticed that the water pump (in the cellar) was still running, even though no taps were on, no hose on, no toilets filling etc. I wasn't sure if this was normal or not (I thought not) so after a few minutes of it running (and some playing on/off with the taps), I switched off the pump and left as I didn't want to leave it running.

Is this normal under typical operating conditions or does it suggest something wrong with the pump?

Thanks for any help!

 

[Harvest Fields]

No. If it is running with no demand, then there is clearly something not right. What make and model of pump is it? Did switching it off and back on again stop it from happening? And can you get a picture?

 

[Lambchopper]

No. If it is running with no demand, then there is clearly something not right. What make and model of pump is it? Did switching it off and back on again stop it from happening? And can you get a picture?

I'm not there now, but I'm glad I switched it off before I left. I'll try to get a photo of the set up and details etc. tomorrow. Switching it off then on didn't seem to help (though in hindsight I didn't try running the taps between switching it off then on).

 

[cr0ft]

There are two types of pumps, negative head and positive head (well actually there's a third type - universal, although these just switch between negative and positive head as required).

Negative head pumps operate when a pressure switch detects a drop in pressure within a pump (think tap opening somewhere and pressure dropping in the pipework). Positive head pumps use a flow switch - when the tap opens they sense water flowing through the pump and they start up accordingly.

Logic dictates that for them to be pumping all the time you must either have: -

1.) A leak on the supply pipework from the pump or on an appliance.
2.) A faulty pressure switch/flow switch.
3.) A faulty PCB on the pump.

Easy way to test which one it is. On the outlet(s) of the pump you will have some isolation valves. Simply close both of them (turn the screwdriver slots across the pipe) and see if the pump stops. If it does then the fault is down to a leak somewhere as per 1 above. If not then suspect 2 or 3.

Source: -

Pump Faqs, Pump Troubleshooting - Stuart Turner Pumps

 

[Harvest Fields]

There are two types of pumps, negative head and positive head (well actually there's a third type - universal, although these just switch between negative and positive head as required).

Negative head pumps operate when a pressure switch detects a drop in pressure within a pump (think tap opening somewhere and pressure dropping in the pipework). Positive head pumps use a flow switch - when the tap opens they sense water flowing through the pump and they start up accordingly.

Logic dictates that for them to be pumping all the time you must either have: -

1.) A leak on the supply pipework from the pump or on an appliance.
2.) A faulty pressure switch/flow switch.
3.) A faulty PCB on the pump.

Easy way to test which one it is. On the outlet(s) of the pump you will have some isolation valves. Simply close both of them (turn the screwdriver slots across the pipe) and see if the pump stops. If it does then the fault is down to a leak somewhere as per 1 above. If not then suspect 2 or 3.

Source: -

Pump Faqs, Pump Troubleshooting - Stuart Turner Pumps

Normally it is either point 2 or point 3

 

[Lambchopper]

I popped round yesterday to get pictures etc, and when I switched it on, it seemed to have sorted itself. Cycled the taps a few times and it switched off as expected. Thanks for all the help, hopefully it's sorted but I'll tell my mum to keep an eye on it.