baxi 105e will not reset?

can you check if you have continuity across the safety thermostat. if yes change pcb. when cool if you have more than 1.5ohm change the stat.
if all checks ok locate the flue stat, its at the top by the fan in the middle is a reset push it if its don't reset its faulty / or you have a problem with the flue itself.

hi-spec plumbing
March 2007

1.5 bar is normal

hi-spec plumbing
March 2007