Baxi 105e problem

[Daubs8]

Hi Lads (and lasses).
Yesterday I removed a radiator from the system to relocate onto another wall. I filled back up and since then I have had problems with my Baxi 105e.

The light warning of a flue or fan problem came on and the boiler wouldn't fire up. I have followed the fault diagnosis flow chart, pump runs, flow switch operates, fan runs and replaced the APS to prove it. I am then led due to no spark at the ignition electrodes to a faulty PCB (I know the 105e is notorious as I have changed three in ten years). 
So, I purchased one this morning and changed it. Strangely the fan wouldn't work on the new PCB so I assumed it was faulty and exchanged it. Unfortunately the newer PCB also won't allow the fan to work? This has completely done my head in! I won't know if the new PCB will allow a spark until I now get past the fan not working with the new PCB's?!
Could it be that the replacement PCB (part number 5112380) needs altering in any way to work with the old 105e? Surely two new PCB' can't be faulty?

My logics are at an end so any thoughts are much appreciated.Thanks.

     

 

[45yearsagasman]

Have you held the reset switch in the reset position for a few seconds?

 

[Daubs8]

Yes did that Pete. I'm wondering now whether it may need a dip switch setting or the wires moving about on the PCB to make it compatible? I'll be calling Baxi technical first thing if I can't sort it?

 

[dcawkwell]

Pressure switch?

 

[Daubs8]

I'll update you. The fan/flue problem was resolved when I found the Venturi in the flue had melted! A replacement fixed the flue problem but then I had a worse fault.
The 30 and 40 degrees lights were flashing and the boiler was shutting down immediately on demand?! I checked everything and concluded it must be down to electrics. I tested EVERY wire and had continuity on them all. I wasn't able to test the gas pump sealed plug however, I did open it up and found all sorts of components which I couldn't test.
Convinced it must be an electrical fault I got on good old eBay and drove 100 miles this morning to pick up a replacement FULL boiler for £7.50!!

I changed my full wiring loom with the one off the 'new' boiler and it fired straight away!!

I have read of other people giving up with a similar problem unable to fix it. Hopefully this may help others in the future?

Thanks for the help.