Recent content by runnerman

Sorted! The problem is the microswitch on the HW valve actuator. I will replace that actuator Monday and we should be ok. Many thanks for all your help and tuition on the basics of control system.

The switched live wire is live. The switched live terminal is dead when the wire is disconnected.

Thanks for your ideas. 1) The problem was not associated with any recent work on the system so I have not suspected incorrect wiring - It was fine for the previous six years or so. 2) The switched live to boiler remains live irrespective of controller commands whenever the mains isolation...

My Potterton Profile 100e boiler ignores all Honeywell ST699 controller settings. The system is fully pumped with separate two port valves for HW / CH. The boiler lights when the main power switch is turned on and responds to the boiler thermostat but no longer takes any on/off instruction from...