Yes
Replace the wiring from the Primary
PCB to the User Interface PCB
87
NO CONNECTION TO PRIMARY PCB
88
NO CH BUT CYLINDER TEMPERATURE OK
Check the wiring from the Primary PCB to the User
interface PCB is securely connected at both ends
Are the Timer and Room Thermostat calling for Heat?
Turn power Off and On, does the fault disappear
Are the Radiator Valves open?
Does the zone valve move to the appropriate
position?
Is an Ideal Electronic Programmable Room Stat
connected?
Is there 230Vac at (A)?
Replace main PCB
No
No
Yes
Yes
No
Yes
Yes
Yes
No
Yes
Yes
Ensure that the Timer and Room
Thermostat are calling for heat
Open the Radiator Valves
Consult Electronic Programmable Room
Stat Fault Finding Instructions
Check Zone Valve and Zone Valve wiring
There is no voltage from the Timer/Room
Stat. This is not a boiler fault. Ensure
voltage is supplied to the boiler by
correcting external wiring