Pcb ?

How do you know the old pcb is faulty?
What tests have you done on the old pcb to prove it is dead?
Have you checked the pcb 3.15amp fuse?
The pcb on an isar is one of the easiest pcbs to change
Can be replaced in under 2 minutes
The molex connectors are idiot proof
Impossible to mix up
The only trouble most people have are inserting the jumper links to configure the pcb to the boiler model

Q
August 2015

switch off electric supply to boiler get to control panel , undo cover of PCB ,take photos of connection
take out connection one by one all connection are fitted lock in push fit you need small screw driver to unlock connection all connection are different so cant go wrong or mark it with colours ,once connection out undo screws holding PCB ,down lord ideal stelrad manual

ltd
August 2015