Gloworm Fuelsaver Complheat 65 Burner Problem

[maco]

Gloworm Fuelsaver Complheat 65 / Unvented Hot Water Cylinder

Hi

Can you shed some light on this problem.

The Boiler will function for 1 hr from cold, heating the rads and hot water. After this time when the boiler needs to 'fire up' the PCB neons will only light to number 3, number 4 neon struggles and then gives up. Fan and pump are working but the burners fail to ignite even though pilot is alight with ignition sparking continually .

Prior to this problem I had removed and cleaned the LP switch and also replaced the TPRV on the hot water cylinder.

Any suggestions

maco

 

[maco]

I've noticed arcing across the PCB when ignition is sparking. Need to check electrode lead/connection for poor connection.. Otherwise it'll have to be a replacement PCB !

maco

 

[geoff@cetltd]

Well, what a surprise, it's sparking across the spark gap

It sounds like you have a flame sensing problem

 

[maco]

Is the PCB suppose to arc?

maco

 

[maco]

Raden, what spark gap you talking about?

maco

 

[HarrogateGas]

Sounds like the flame sensing electrode is breaking down during heat.

 

[maco]

Don't have a flame sensing electrode.
Will check if live across the main gas solenoid black and blue cables. Otherwise it must be the PCB.
Have good contact electrode lead/ connection.



Power to pilot solenoid OK
Pilot ignites

when cold
Ignition spark switches off and main gas solenoid opens

when hot
Manually depress main gas solenoid actuator, ignition spark switches off and burners alight.


maco

 

[HarrogateGas]

Don't have a flame sensing electrode.
Will check if live across the main gas solenoid black and blue cables. Otherwise it must be the PCB.
Have good contact electrode lead/ connection.



Power to pilot solenoid OK
Pilot ignites

when cold
Ignition spark switches off and main gas solenoid opens

when hot
Manually depress main gas solenoid actuator, ignition spark switches off and burners alight.


maco

dont have a flame sensing electrode???................well pray tell me.........exactly how does this boiler sense when it has lit the pilot?? I think you will find it has a combined spark and sensing electrode. Or does it just make an educated guess or maybe just take a risk??!!!

 

[geoff@cetltd]

Raden, what spark gap you talking about?

maco

depending on which pcb (there are three possibilities), there are two spark gaps. One is a glass tube with metal contacts on each end which causes the transformer spark, the other is a slot in the pcb which isolates the "earth" side of the secondary from boiler earth

There is only one electrode, which doubles up as spark electrode and sensing electrode