Combi boiler quetion

skiTTish

hi ,having never had a combi boiler ,not sure if this is normal ..but ..
It keeps turning on for just a couple of mins during the night ,no one is running hot water and rads not on and not cold enough for the thermostat to kick in .

thommy

It depends what model you have. Ours is an Alpha, 1 year old. It is meant to do this - something to do with regulating/optimising itself.

Karl.P

The normal cause is the hot water preheat functionality, this helps you get hot water much quicker after turning on the tap by keeping some in the boiler nice and toasty ready.

Many boilers allow this to be turned off (to save energy), though it can be a engineer internal change on some (older models), newer models it could be just a case of using the manual to work out the key sequence.

If its more than a few minutes, it may be a sign the divertor valve is not properly sealing off the CH (a tell tale sign is raditors getting warm when running the hot water), this should be fixed by a suitably experienced plumber, as it will be wasting energy, and may also make your shower not very hot.

redlooney

Ours does it regularly - quite natural