Lennox Rooftop Unit LGH152

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 screws from the bracket supporting the vent connector

Ensure all motors are lubricated at the factory

Verify that no further lubrication is required for factory-lubricated motors

Blower Shaft Bearings Lubrication

Check if blower shaft bearings are prelubricated

Is relubrication required for extended bearing life?

Select the grease to be used for relubrication

Use a hand grease gun for relubrication

Add grease until a bead appears at the seal lip contacts

Remove the combustion air inducer assembly as described in the Combustion Air Inducer subsection

Clean the flue box with a wire brush as required

Clean the tubes with a wire brush

Replace gaskets during reassembly

Label all wires prior to disconnection

Verify proper operation after servicing

Check and replace filters as necessary

Was the service completed by a qualified technician?

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 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 the unit