Boiler has a mind of its own

[Robbai]

Can anyone help

I have a gloworm ultimate boiler, hot water tank 2 x 2 way valves, room stat, tank stat, my pump runs non stop and the boiler fires up at any time day or night, even after the programmer has shut down, i have replaced the room stat and checked the 2 x 2way valves all seems to work okay, i guess that the fault must be in the wiring or the boiler, any thoughts would be grateful.

Rob

 

[namsag]

Disconnect 1 orange wire at a time on each motorised valve wire at the junction box and see which one stops boiler and pump firing ,
This will be valve with a stuck microswitch.
Careful there could still be live at the wire when its disconnected

 

[Robbai]

I have disconnected the orange wires, no difference on either, i have replaced the room stat, and checked the tank stat all seem to be working okay, i have traced the pump wires they go to the boiler via terminal block,
i guess that the problem lies in the boiler.