Central Heating not turning off, thoughts and advice.

[acprc]

Hi all,

New to the forum but been lurking for a while. Joined to tap into the wealth of experience that might help me with an ongoing issue.

We have an S plan system that has CH that won't turn off as programmed. My initial thought was that the motorized valve for the CH was faulty but the valve works when you power on and off the system. By this I mean when the power is off the return spring closes the valve and you can then turn power back on. Heating switches on ok but not off.

So far I have changed the programmer and backplate to a newer Honeywell 9400C, fitted a new Honeywell wiring centre, fitted a new motorised valve head (physical valve is the same) and as it was cheap at £35 a new boiler PCB. (Boiler is an older Glowworm Complheat 40).

We don't have a wired or wireless thermostat anywhere in the house.

What am I missing, could the physical valve still be at fault, even though it motors on ok when heating turns on. I can post pictures of the wiring centre if needed.

Any help, thoughts or experience is welcomed.

Adam

 

[Rickster123]

You're missing the correct qualification to change pcbs. You've spent more on bits than it would've cost to get somebody qualified in to do it for you.
Thread closed.
Merry Christmas.