Lennox Baltic BHK 070 - Page 74

IOM / ROOFTOP BALTIC Series - 0704-E Page 73
HEATING: gas burner
GAS BURNER FIRE-UP SEQUENCE
Gaz low pressure switch?
Operation from control
Thermostat GAS = Closed
Supply Thermostat Limit ?
(Auto reset)
Gaz ignition control block signal
Extraction Fan ON
Air pressure switch ON
Backfire thermostat ON ?
Pre-ventilation 30 seconds
Fire-up Electrode 4s
Gas valve open
Ionisation 1 second after
the end of sparking ?
Gas valve remains open
Normal operation
Air press switch ON
or Backfire thermostat ?
Signal from ionisation
probe still ON?
Gas control
Valve closes
BURNER
STOPS
Gas control
Valve closes
BURNER STOPS
Fault on Gas
control block
6 minutes Delay
FAULT ON CLIMATIC
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO