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beesley121

Hi guys,
Having a problem with a ideal isar 35HE.
its giving a fault code of LF - no gas
replaced gas valve and the programable user control panel as that wasnt working as it should. It fires up ok and runs CH fine but when it tries to relight again, i get the LF fault code again. I then have to reset it via the user control panel and it works fine again until the boiler goes off and then needs to come back on. same sequence of events
anyone know what can cause this? could it have anything to do with the control panel as the previous one was a digital programable one but I only have a manual control panel from a isar 24he on the van and assumed they were compatible
advice much appreciated
 
Hi beesley121

LF code, have you checked the condensate trap and pipe work?
 
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hi mate, im surprised the user control was compatible but if it works!! lf dosent necesarily mean no gas, its the most common code on isar, i'll list what it could be if u like so u can go through it

pcb (doubt it though)
ioisation probe (bent or not making connection back to the board)
blocked trap (sump cover got water behind it)
heat ex leaking and water getting down the blue sensing hose that goes to the gas valve (always a good en!)
slow fan (red chalky stuff falling out the bearings sometimes)
heat ex has ran dry at one point and the ionisation lead has melted to the side of it!! ( another good en)
bent ignition probe
spark generator ??

i used to work for em so just letting u no lt can be anything!!
the boards are made in japan and the lf has absolutley no reference to anything english!

hope this helps,
jon
 
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