I checked the valves by pushing the levers - on the odd occasion when the boiler did switch off, the levers for central heating and hot water were stiff. Worcester Bosch say that when the frost stat works it does not actuate the central heating pump. The Worcester Bosch engineer (who has been 5...
Thanks, Dan. All the zone valves are working correctly. I called Honeywell and they suspect the wireless receiver has developed a fault. A replacement has been ordered.
My Worcester Bosch external Camry oil boiler cannot be switched off by either my timer or the room thermostat. Both devices are Honeywell and the problem has arisen in the past couple of months after 9 years of problem-free operation. I have reset the wireless thermostat HCW80 and re-linked it...