Ideal Isar HE35. No display. Power in several wire blocks. Dead parrot!

[JohnHuson]

Yea I know it is a bad product. No display at all, nothing happens when switching on.
have checked resistance across the fan on two outer contacts and is open. When power applied there does not appear to be an active supply to the fan anyway. No attempt to ignite.
Tried two PCB's from working boilers.
The pump is free. There is power going to the PCB. No positive power to the fan or Diverter valve motor.

Happened after changing the wireless Salus thermostat but this could be a coincidence.
Pressure is OK after I decided to clean the diverter cartridge and re-pressurised. Expansion pressure is OK too.

Basically what I need to understand is what will stop everything, but power is about, and blank the display please?

As there is no display there is no troubleshooting code to work to.
Any help will be appreciated. Thanks.

 

[DP]

Off the block, nothing wrong with that boiler

Gets a bad name because folk do not understand the operation

Fan is not a notorious that only has voltage across two tags

If boiler dead, am almost certain the fault finding guide covers the scenario too

 

[ollski]

Have you managed to swap the two 4 pin connectors round when you swapped out the first pcb?

 

[DP]

Have you managed to swap the two 4 pin connectors round when you swapped out the first pcb?

Have done that too
Learnt the hard way

 

[JohnHuson]

Yes I did ensure the jumpers were in the right place. I have just replaced the fan control panel, wiring harness and
diverter motor. I can pick up positive feed supplies to the PCB but still no lights on the front control panel.

I am not sure what else I can do?

 

[breadnbutter]

there is a fuse in the pcb you can check that is not blown, its top left, in a black plastic holder.
have you voltage and checked polarity. might be a dodgy neutral.

 

[ollski]

Yes I did ensure the jumpers were in the right place. I have just replaced the fan control panel, wiring harness and
diverter motor. I can pick up positive feed supplies to the PCB but still no lights on the front control panel.

I am not sure what else I can do?

Not the jumpers, the actual 4 pin power supply cable. Is the connection to the display ok i.e. Not corroded