Lochinvar Condensing Boiler FBL3501

Inspect flame through observation windows

Is the flame satisfactory at both high fire and low fire?

Remove and clean the burner using a vacuum cleaner or compressed air

Do not use compressed air to clean the burner if cleaning is performed inside a building

Shut down the boiler following the 'To Turn Off Gas to Appliance' instructions

Do not drain the boiler unless it will be exposed to freezing temperatures

If using freeze prevention fluid in system, do not drain

Flue Vent System and Air Piping Inspection

Visually inspect the entire flue gas venting system and air piping for issues

Repair any joints that show signs of leakage

Verify that air inlet pipe is connected and properly sealed

Are the boiler vent discharge and air intake clean and free of obstructions?

Check air and vent termination screens

Record the flame signal at high fire for each combustion system

Is the flame signal at least 10 microamps?

Troubleshooting Low Flame Signal

Clean the flame sense electrodes

Is the ground wiring in good condition?

Is the ground continuity satisfactory?

Replace the flame sense electrode if issues persist

Inspect boiler ground wire from the heat exchanger access cover to ground terminal strip.

Verify all wiring is in good condition and securely attached.

Check ground continuity of wiring using continuity meter.

Is the ground continuity satisfactory?

Replace ground wires if ground continuity is not satisfactory.

Follow the 'To Turn Off Gas to Appliance' instructions

Is the boiler exposed to freezing temperatures? If yes, drain the boiler unless using freeze prevention fluid.

Allow boiler to cool to room temperature

Remove the gas/air manifold assembly

Remove the nuts securing the burner to the burner mounting plate