Frost stat keeping pump running all night?

[barki]

Hi all,

Last two nights my CH pump has been running all night.

My setup is:

- Grant Vortex oil boiler, floor mounted in a protected but unheated cold area (detached garage).
- Honeywell frost stat mounted directly above the boiler.
- Unvented heatrae sadia megaflow cylinder.

We don't call for heat on either DHW or CH from about 6pm until 6am and previously during very cold weather ive heard the pump come on periodically to prevent freezing, fair enough. However the last two nights (which have been around -5c outside) the pump has been runnimg all night. It doesn't go off again intil after the next call for heat which is 0600-0700.

While the pump is running its not burning oil and not heating the rads or tank, but is it keeping the pump area of the boiler pretty warm.

Do I need to sort this out? I'm not panicking becauee I'd rather it didnthos than freeze, butnim worried about a) the electric bill and b)having a broken pump soon.


Cheers in advance,

Tom

 

[oldbutnotdead]

It should be fine as long as you don't have motorised valves or there is a properly set up bypass valve (or radiator) somewhere on the system- means the pump isn't working into high resistance.
Power consumption- worst case (old fixed speed pumps) 3p an hour. Less on modern pumps