Lennox Rooftop Unit LGH120

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 blower shaft bearings?

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

Filter Inspection and Replacement

Check the condition of the filters

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

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

Are the new filters installed correctly?

Is the unit free from any damage after filter replacement?

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

Inspect the following components for corrosion, deterioration, or debris deposits

Remove any obstructions or blockages found during inspection

Refer to Figure 5, Figure 6, or Figure 7 for detailed diagrams

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 the flue box cover gasket.

Replace the combustion air inducer gasket.