Worcester Greenstar 37CDi combi - the pump is running constantly for hours on end despite the system being on Auto and the temperatures above the set programme, also the guage shows 59 degrees which seems to indicate the boiler is heating the water but none of the rads is warm. Is this normal?
I have just uprated a rad and refilled the system and it has had its annual service.

thescruff wrote on Aug 10^th, 2013, 2:36pm:

Must be a PCB fault since the manual states that the anti seize cycle should only last a few seconds whereas mine lasts for hours. Anywhere I can get a schematic so I can see what's involved?

Only really noticed it recently since the rad change. I have switched the boiler off a couple of times (will that reset it?) but pump comes on almost at once. Tried the reset button same result.

Thanks for telling, always worth knowing  

What is the make/model of the stat/receiver please.