Set Appliance State:

CH Demand
Turn the CH temp control knob to the 10 o'clock position
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Carry out procedure below to operate boiler at maximum rate:
  • Once boiler has lit turn the CH control knob fully clockwise, back to 10 o'clock, then fully clockwise again.
    'S' should now be displayed and the boiler will fire at minimum rate.
  • Turn the control knob to the 10 o'clock position and back fully clockwise one more time.
    Boiler should to ramp up to maximum rate (fan speed increases).
    Carry out a gas rate as per TOPs / company procedures.
    Is the gas rate correct for the appliance data plate?
    Note:
    To take the boiler out of service mode remove the demand or adjust control knob.