Pump permenantly on .... driving me nuts.

[ypres]

We have a Potterton Prima 30F (boiler). When the hot weather is upon us (because in winter this problem doesnt happen), the pump is permenantly on when the controller has the heating and hot water 'off'. Even when the heating is 'on'and the thermostat is set low, the pump is on.

We eventually end up switching the whole system off (electrically).
When we switch the system on in a morning the pump plays its usual song (immediately)

Question. Am I right in thinking that the pump is controller by the 'Pump over-run thermostat' and that if we replace this item, peace and quiet will once again rule ?

Question. If the answer to question 1 is 'yes', can we do this job ourselves.

All help gratefully received...

 

[ChrisR]

Not sure if the smaller Primas had a pump o/r stat, but if they did then yes that's most likely and you can change it yourself.