My Baxi 105e has recently developed a problem! On Saturday expansion vessel packed in and leaked. I dried everything out, relit and pressure went upto 3 bar. Turned boiler off to cool down and it wouldnt re-light. Fault guide was flashing at flame failure,indicating gas valve failure or faulty pcb. I've replaced PCB, gas valve and expansion vessel. Still can't get the boiler to light. Any one out there shed any light cos i'm all out of ideas now?!
Thank you Kash, spark generator is sparking, everything goes through the motions, fan kicks in etc just seems that gas isnt getting through. I replaced both gas valve and pcb yestarday still no joy!
Damian Robinson, December 2012
first i would check is the overheat stat the safety thermostat it the first thing to check when the boiler overheats and u need to reset the boiler by holding the the control on r for 30secs or so to get rid of the fault code then turn it to 0 and back on again. see if u can here the the spark generator clicking and check for a spark when the boiler trys to fire. if there a spark but no ignition then its a faulty gas valve or pcb. if there is no spark then gas valve does not come into play as yet check the spark electrode. its a matter of checking each component 1 at a time
