Lennox Rooftop Unit LGH300S/U

Filter Inspection and Replacement

Check the condition of the filters

Is the air flow direction marking visible on the filter frame?

Reinstall filters ensuring correct air flow direction

Replace factory-installed filters if within 30 days of initial unit start-up

Replace temporary filters before building is occupied

Refer to local codes or appropriate jurisdiction for approved filters

Ensure filters are replaced with approved filters to prevent damage to unit

Turn off the electrical power to the unit

Turn off the gas supply to the unit

Remove the appropriate component based on unit type

Disconnect the pressure switch air tubing from the combustion air inducer port

Remove and retain the screws securing the combustion air inducer to the flue box

Remove and retain two screws from the bracket supporting the vent connector before removing vent connector

Turn off the electrical power to the unit

Turn off the gas supply to the unit

Remove the burner compartment access panel

Remove screws securing burners to burner support

Lift the entire burner assembly from the orifices

Label all wires prior to disconnection

Ensure all safety equipment is in place

Disconnect wires with proper labeling

Inspect control wiring for damage

Verify proper operation after servicing

Ensure all necessary tools and materials are available, including a hand grease gun and lithium base grease.

Select the lithium base grease to be used

Verify that the motor is turned off and properly secured.

Clean the area around the bearing to prevent contamination.

Attach the hand grease gun to the bearing fitting.

Pump grease into the bearing until a bead of grease appears at the seal lip contacts.