Ideal Icos fault H1

[tecnamflyer]

I have changed the flow Thermister although its resistance is exactly the same as the old ones. This is fed by a pair of red wires. My boiler does not have a return Thermistor although it has the two blue wires in the harness that the wiring diagram showgo to a return Thermistor but it just ends in a plug not connected to anything. The parts list in my book lists two control thermistors, same part no 170917 but the exploded drawing does not have a return one shown fitted. The other two wires in the plug are yellow and these go to the flue Thermistor. Again good continuity and the flue Thermister resistance is around 11k ohms at room temperature. (Cannot find a value anywhere in the fault finding pages)
The plug pins in all the connector blocks to PCB seem sound. The input voltage at the plug into the board is 237-238v



But I am now baffled. The fault finding book says if all else fails, change the PCD, I bought a new one and still have the same fault.
Help gratefully received
Thanks,
Paul

 

[lightning]

call a heating engineer in as you dont have a clue, could told you its not the pcb

Paul

 

[Dan Robinson]

+1

 

[colin786]

Ignore my post.

 

[tecnamflyer]

I had hope for some constructive help from this forum, not insults.
Paul

 

[Dan Robinson]

What insults?

 

[gasright]

I have changed the flow Thermister although its resistance is exactly the same as the old ones. This is fed by a pair of red wires. My boiler does not have a return Thermistor although it has the two blue wires in the harness that the wiring diagram showgo to a return Thermistor but it just ends in a plug not connected to anything. The parts list in my book lists two control thermistors, same part no 170917 but the exploded drawing does not have a return one shown fitted. The other two wires in the plug are yellow and these go to the flue Thermistor. Again good continuity and the flue Thermister resistance is around 11k ohms at room temperature. (Cannot find a value anywhere in the fault finding pages)
The plug pins in all the connector blocks to PCB seem sound. The input voltage at the plug into the board is 237-238v


But I am now baffled. The fault finding book says if all else fails, change the PCD, I bought a new one and still have the same fault.
Help gratefully received
Thanks,
Paul

Faults like this are usually the flux capacitor, have you looked in the manual for where it's located?

 

[Agile]

Not an overheated BBF then ?

 

[DeletedUser]

It's obviously the ionisation probe aka the spark electrode,but you'll need an rgi to confirm and fit.

 

[tecnamflyer]

It does not get as far as a spark as it fails on the PCB checking the flow thermistor.