Ideal Logic System IE Gen 2 fault F09

PCB fault

Gas boiler

What it means

Fault indicating a failure of the main printed circuit board.

Likely causes

  1. Faulty PCB
  2. Boiler mode set to Off on display
  3. CH Timer or Room Thermostat switched off
  4. Radiator valves closed
  5. No voltage supplied from Timer/Room Stat wiring (external fault)
  6. Missing link wire across OpenTherm connections when no OpenTherm Room Stat connected
  7. No 230V at SL2 IN when Outside Sensor connected
  8. Faulty wiring from terminal strip to PCB
  9. No voltage supplied from Timer/Room Stat to SL1 IN (external wiring fault, not boiler fault)

Where to start

  1. Remove and retain screw
  2. Carefully release the four retaining clips and remove control box cover
  3. Unplug all lead connections to the PCB

The full answer, free

  • 20 more checks in order
  • The readings and component tests from the manual
  • How to put it right, step by step
  • The manual page for this fault (page 49), right under the answer

Safety: Isolate gas and power before you open the case. If you have been into the gas side, do a tightness test, and a combustion and flue check before you hand back. Gas Safe (UK) or RGI (Ireland) work only.

From the Ideal manual for the Logic System IE Gen 2. Check the model on the data plate before you order parts.

Other Ideal Logic System IE Gen 2 fault codes