27/30
Burner lights
but will not hold
on main flame
Gas pressure
Excess combustion air
Combustion air too low
Check flame probe
Check head pressure as
per manual
Check setting of air flap
Check head setting
Position
Check inlet pressure
Check CO
2
level at flue
Adjust air flap
Adjust head setting
Check control box
Signal
Check main gas actuator
Burner lights
but will not hold
on main flame
Insufficient air
High inlet Pressure
Fan limit stat
Air inlets blocked
Outlet nozzles closed
Duct resistance too high
Fan belts slipping
Remove obstruction
Clean filters
Open louvres on nozzles
Open duct Grilles
Incorrect gas pressure
Warm air recirculation
Adjust nozzle position
Mains pressure
Head pressure
Incorrect settings
Faulty
Adjust to manual
settings
Reset
Replace
Adjust fan belts
