Please help! Boiler ch pump always on!

ian.settle1 · Mar 7, 2015

When you say a new home do you mean a new home for you or a brand new built home?

If it is the later I would not be playing with it but get the builder on to it as it should be under his warranty period.

LankyWill · Mar 7, 2015

What cables do you have in the programmer. Where do they go? (Joint in airing cupboard most likely). Are you an electrician of any sort?

UNG · Mar 7, 2015

Before changing things you need to get a meter out and do some testing

LankyWill · Mar 7, 2015

Has this problem recently occurred? If yes then I doubt it's a wiring fault and more likely faulty equipment.

UKMeterman · Mar 7, 2015

Some boilers are known for having faulty overrun timers and make the pump run 24/7 !

123 · Mar 7, 2015

LeeD said:
No because the burner comes on and the utility room where it is sited is tropical to say the least

So the pump and the burner are running?

Looks to me like you have a faulty zone valve as per post #6

ruston · Mar 7, 2015

If it is firing the boiler too , and it is only the utility room that is hot, do you have a hidden frost stat somewhere set wrong?

Leesparkykent · Mar 7, 2015

Do you have a manifold for the under floor heating with a separate pump?

LeeD · Mar 7, 2015

LankyWill said:
What cables do you have in the programmer. Where do they go? (Joint in airing cupboard most likely). Are you an electrician of any sort?

From the fuse spur it goes into a connector block, from here you have a link for the programmer live, you have the underfloor heating feed and a black labelled 1 to the boiler. In the second connector block there is a grey to the underfloor heating and black labelled 6 to the boiler. In the third connector block black labelled 5 to the boiler and a grey from a 3 core +cpc labelled SBJ. Neutrals all linked in a block too and lastly one twin and earth dead ended in there.

Im an electrician but always worked on streetlighting contracts as a cable jointer so this is not my forte!

There isn't an airing cupboard as it's a combi. Could it possibly be a faulty stat upstairs?