Vokera Linea 24 stuck in loop

[Jongleur]

Hi, I have a problem where the boiler is getting stuck in a loop where it is firing up then cutting out every few seconds. Strangely this only seems to happen when the tumble dryer is on and the room warms up a bit.(This may be a red herring but I thought I would mention it incase there were any common electronic issues that may cause this fault .I would have thought the heat of the boiler itself would trigger it though). Letting the boiler cool down for twenty minutes seems to fix the problem temporarily. The fault is normally only noticed when hot water is called for.

So far the system has been flushed and the heat exchanger cleaned. The engineer helping me with this problem did contact Vokera to see if they could help but unfortunatly not.

Any help or ideas would be greatly appreciated thanks.

 

[nickso]

if it fires up and goes off in rapid succession it normally indicates the gas valve pcb is faulty. it should do this on both ch and hw though.

 

[Jongleur]

Thanks for that, I do think it does happen when the CH is on as well, but i have only really noticed it happening when my wife starts yelling halfway through having a shower!

Thanks again.

 

[scatmanjohn]

I agree with nickso.

Its usually the ignition pcb thats fastened to the gas valve.

 

[matgasplumb]

i had a identical call out last week on a vokera linea 28, scratching my head for a while checked thermisters they were ok, and it only seemed to happen on hot water or when heating got up to about 60 degrees...
any way changed the ignition pcb on side of gas valve and that fixed that..

 

[Nixt]

Check CH operation fully, if it works and flame modulates then gas valve, PCB, CVI/ign box, APS and fan are all OK. Then in dhw mode check for signs of overheating eg. very hot internal flow pipe from main heat ex