Have any of you seen this fault

[5TIMES]

helloo, come across this fault on a worcester 24i junior (first model) boiler running for say 5 mins flames hanging all over combustion chamber, voltage droping off the fan from the pcb, but voltage staying on the gas vlv keeping the burner on!.

 

[5TIMES]

sorry my question was have any of you seen this fault on this boiler, an was is a defo pcb fault.

wonder why the voltage just drops off the fan tho

 

[OLLIE20]

What was it? PCB usualy is on 1st I range, mind you and the 2nd

 

[OLLIE20]

sorry that wasnt there when i replied.

 

[OLLIE20]

Could it be that the part of PCB that controls Voltage to fan has had it, but the thermistors that sens the temp and send voltage rqd to the modureg on the GV via PCB are ok, strange if the flames are all over is doesnt drop out on the sense elctrode though

 

[5TIMES]

been there 2 flipping hours! just as i was having a swig of me coffee i noticed the burners everywhere, i threw my multimeter on the fan connection on the pcb no volts, went threw an tested APS, thermistors,
tell you what i also noticed the fan is twin speed, pulled the modureg lead off to drop it down to min, 9.5mlb! just wondering now if its because the fan is running slower on minimum rate an the burner pressure is too high

my head hurts had a meeting till 2 then 5 repairs!

any help will be appreciated

 

[Corgigrouch]

I have seen this issue on this model boiler a few times.. Not one of Worcesters best efforts

 

[OLLIE20]

So what happened when you set min B.P. correctly, still cant fathom why burner would be on atall if no voltage from pcb to fan?

 

[nickso]

the pcb generally provides a voltage and then stops. for what ever reason the APS dropping out is not acknowledged and the burner can stay on for a long period after.

i carry a PCB in the van now its that common.

 

[OLLIE20]

the pcb generally provides a voltage and then stops. for what ever reason the APS dropping out is not acknowledged and the burner can stay on for a long period after.

i carry a PCB in the van now its that common.

Yeah PCB's on these always faulty, i also carry one on my van

 

[5TIMES]

bloody hell nice one just to mention I replaced the APS because there was a hole in the diaphragm the other day.. Boiler wasn't working at all then tho.

thank u ill press th button

 

[5TIMES]

So what happened when you set min B.P. correctly, still cant fathom why burner would be on atall if no voltage from pcb to fan?

have to alter this, my allen keys are plastic coated an dont fit in the valve!

bastard..

 

[OLLIE20]

So what happened when you set min B.P. correctly, still cant fathom why burner would be on atall if no voltage from pcb to fan?

have to alter this, my allen keys are plastic coated an dont fit in the valve!

b*****d..

Just what you needed, one of THOSE jobs ey

 

[5TIMES]

tell me about it! tell you what tho its nice being able to bounce things off other people doesn't half help me sleep

 

[Happyplumber]

I have had this problem countless time and yes this pcb is one of those i always have on the van,first time i saw it i shat meself too!