glow worm micron 60ff central heating fault

[smmjh11]

Hi

Does anyone know why a glow worm micron 60ff boiler works fine when the hot water is on but when you want central heating nothing happens intermittantly. If it is left for a day it will seem to start working but then stop working a couple of days later. Room stat switch seems to be working OK, power ok from the programmer, power to the diverter valve but boiler just does not fire up. It seems the PCB board is still the original as only 2 neon lights on it for the reset and burner on although I have read that some PCB's have 6 neon lights. Am I missing something or is ther different controls for central heating and hot water on the PCB.

Many thanks for any responses in advance

 

[Agile]

Your boiler is a simple heat only boiler. It does not know where its heat output is going.

The problem is likely to be the motorised valve auxillary switches if the room stat is OK.

Tony

 

[smmjh11]

Thanks tony