Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4
Remove the two flue clamps and the condensing heat exchanger elbow

Observation:

Check:
  • The fan venturi is free from restriction or blockage and is undamaged.
  • The condensing heat exchanger flueways (viewable after removing the flue elbow)
    are not blocked or restricted.
  • The seal between the flue elbow and the condensing heat exchanger is undamaged.
  • The flue clamps are undamaged and fit securely to the fan / flue adaptor / flue elbow.