MAIN 24HE Boiler Question - Hot Water but Limited Burner Activity on CH

[vards01]

Hi All,

I have a situation where the boiler (combi) intermittently fails (more often fails) to ignite the burner when the thermostat is triggered. Also radiators downstairs hardly get warm when it is running. You can hear the fan engage (or maybe this is the CH pump) when the thermostat clicks on, but not burner.

Pressure in the system is OK although it does drop over time and I can see some water underneath the boiler and scale residue on some of the pipework inside the boiler (looking from underneath)

I have bled all radiators and balanced but still I'm having the issues above.

Hot water is absolutely fine no problems there.

Any ideas what the likely candidates could be?

Thanks,

 

[ianmcd]

Could be so many things, you would be better getting a pro in