Glowworm Ultimate 120FF not working due to damaged PCB

[MichaelG]

The boiler stopped working earlier today. It is a direct fed system.
I've followed the fault finding flowchart in the manual.

Seemed to suggest the fuse or PCB.

I removed the PCB to find that the solder joint had melted where one side of the fuse housing was attached to the board. I re-soldered this temporarily but don't trust it. Seems to smolder/heat up.

Have now disconnected and will order a new PCB in the morning.

Any thoughts why this happened and if it will reoccur with a new PCB?
Is something else the route cause?
Was due for it's annual service this month so hasn't been neglected ;o)

Mike

P.S. have had to replace the sparklead several times, There seems to be a design fault where the casing causes it to short after a few years use.

 

[Boilerman2]

Any dry joint (the term for a defectve soldered joint on a pcb) will create heat, due to the increased resistance created by the fractured joint, it is not uncommon to find a 20mm or larger hole burnt through the board, so I suspect a new PCB will be the fix and no worries

 

[mickyg]

if your service engineer has replaced any suprima pcbs lately he might have some left over electrode lead insulation. A bit of this on your lead where it enters the case should help prevent further failures

 

[MichaelG]

Thanks for your replies guys. Really helped ease my mind.

I removed the fuse and shorted the connection to get temporary operation. I did think about replacing it with a fused cable you can get.

But the thought of the root cause returning gave me too many paranoid thoughts.

So took the belt and braces approach and replaced the PCB.
A £100 lighter in the wallet but a weight off the mind

Thanks again. Mike