potterton 24 he ?

Checklist:
Condense clear?

Fan with constant voltage x2 on the board (pins 3&4)?

Gas meter position?
(If outside, could be governor freezing) check the input with manometer as boiler tries to fire, ensure 20mb (17mb minimum) is available.

Constant voltage at x3 plug on the board (pins 1 & 2) whilst trying to light? Also throttle adjustment correctly set? If yes, gas valve issue.

Sensing electrode correctly positioned and burner gap correct (7.5mm +/- 1mm?

Carefree
December 2010