heating works in service mode but otherwise hot water only.

[IanAsh]

Hi, I have a problem with a Main eco 30 combi boiler. Hot water works fine but when heating is called for nothing happens. No light illuminates or anything.

I've found a workaround where if you put it service mode (to change high / low flame) then the heating led flashes along with the hot water light. At this point the pump is running and the central heating system is working though as the boiler is turning the flame on and off during the service mode sequence this isn't ideal and will take a lot longer to heat up the system.

As the heating is working successfully in service mode however why is it simply not responding when the heating is called for otherwise? The system uses wireless stats and then the heating is turned on and off via this the actuator valves open as you would expect but the boiler does not respond otherwise.

Any ideas appreciated. cheers

 

[Deleted member 120897]

If the diverter motor is operating with the room thermostat, then it’s either not energising fully or there’s possibly an issue with the diverter itself.

 

[ShaunCorbs]

Control issue

 

[Lee hetherington]

I have the exact same problem, 2nd year in a row same month it’s happened. Any advice