While you wait for answers, we may have found some information which could help you.
Click here for Heating Pcb Fittedwhy has my wireless time clock stopped responding?
can i fix it honeywell st1000 ?
Honeywell ST7100 programmer goes blank when RUN selected?
Mid position valve?
How do I reprogram my ideal bolier rf thermostat receiver?
heating, Oil boiler not running?