Tribune HE Pump always running

[Stuart13]

Hi,
We have a Tribune HE hot water tank along with a boiler in the garage. It is a new build property and is now almost 5 years old.
In the evening the pump that sits below the hot water tank continues to run even when the heating and hot water are off. We had this problem previously and I was advised to turn down the frost protection thermostat in the garage, and this resolved the problem. However it is doing it again and turning down the thermo doesn't stop it.
I've noticed that if I flick over the lever on the 3 x valves and then let them reset back to their normal position the pumps stops. It's then fine until the following evening when it happens again.
Any ideas anyone?

 

[Dan Robinson]

One of the valves is guffed.

 

[Stuart13]

I guess if I try one valve at a time it might indicate which one?

 

[Hot&Cold]

When the system is at fault a voltage test with a multimeter would confirm if a valve is supplying voltage to the pump.

your flicking idea could be resetting the valve microswitches temporarily or allowing hot water out to lower the temperature during bypass,only onsite testing will tell.

straight forward job for a heating tech