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C. HEATER STARTS BUT IT DOES NOT RUN REGULARLY
a. Heater stops in lock-out and reset lamp is on (red light)
i. Flame failure because of missing fuel
1. Check fuel tank is not empty
2. Check fuel type be correct, clean and without water
3. Check and clean fuel filter cartridge
4. Check all connections of fuel line from tank to fuel pump: untightened connections can cause
suction of air to fuel pump
5. Check fuel line are not obstructed or damaged and eventually replace
6. Check adjustment of fuel pump pressure
ii. Flame failure because of bad combustion
1. Check and clean fuel nozzle (eventually replace it)
2. Check and clean combustion head (nozzle, nozzle support and diffuser disc)
3. Check adjustment of fuel pump pressure
4. Check adjustment of combustion air
iii. Flame failure because of air pressure switch PA not working.
1. Check fan is tightened on fan motor shaft.
2. Check there is no object obstructing air inlet
3. Check hose to air pressure switch are no obstructed
4. Check connections to electrical wirings of air pressure switch
5. Check and eventually replace air pressure switch
iv. Flame failure because of safety thermostat LI cutting in
1. Check there is no object obstructing air outlet
2. Check air outlet hose respect maximum length and diameter as specified
3. Check connections to electrical wirings of overheating thermostat
4. Check and eventually replace safety thermostat
b. Heater stops in stand-by and reset lamp is off
i. Voltage lower than 70 V or higher than 150 V
1. Check supply voltage is correspondent to rating plate.
2. Unit will automatically restart when voltage becomes higher than 80 V or lower than 140 V.
c. Heater starts and stops flames and main fan remains on (unit is in stand-by and rest lamp is off)
i. Air bubbles in the suction line to fuel pump
1. Check oil filter casing is tightened
2. Check all connection on fuel line to fuel pump are tightened
3. Check fuel line are not obstructed
4. Check fuel tank level
D. HEATER RUNS WITH BAD COMBUSTION AND EVENTUALLY WITH WHITE OR BLACK SMOKES
a. Heater runs with white smokes
i. Fuel /air mixing on combustion head is incorrect: excess air or little fuel
1. Check adjustment of fuel pump pressure
2. Check adjustment of combustion air
b. Heater runs with black smokes
i. Fuel /air mixing on combustion head is incorrect: little air or excess fuel
1. Check adjustment of fuel pump pressure
2. Check adjustment of combustion air
c. Heater runs with noisy / irregular combustion wit/without smokes
i. Combustion is incorrect
1. Check and clean fuel nozzle (eventually replace it)
2. Check and clean combustion head (nozzle, nozzle support and diffuser disc)
3. Check exhaust is not obstructed
4. Check combustion chamber is not clogged by soot and eventually wash and clean it
E. WHEN HEATER IS SWITCHED OFF, IT DOES NOT STOP
a. Heater still runs with flame
i. Room thermostat / main switch failure
1. Check room thermostat and room thermostat connections
2. Check main switch on heater control board
ii. Fuel flow to nozzle is not interrupted
1. Check fuel solenoid valve close fuel line to nozzle