Lennox HVAC Unit ML193UH030XE36B

WARNING! ELECTRICAL SHOCK, FIRE, OR EXPLOSION HAZARD.

Disconnect all electrical power to furnace before servicing.

Label all wires prior to disconnecting when servicing controls.

Ensure wires are reconnected correctly after servicing.

Filter Inspection and Maintenance

Inspect all air filters installed external to the unit.

Is cleaning or replacement of filters necessary?

If necessary, clean or replace the filters to ensure proper furnace operation.

Read and understand all safety warnings before proceeding.

Disconnect all electrical power to the furnace before servicing.

Label all wires prior to disconnecting them.

Reconnect wires correctly after servicing.

Verify proper operation after servicing.

Exhaust and Air Intake Pipes Inspection

Check the exhaust and air intake pipes for tightness.

Ensure there is no blockage in the exhaust and air intake pipes.

Turn off gas and electrical power to the furnace

Remove heating compartment access panel

Disconnect the gas supply line from the gas valve

Disconnect and label wires from gas valve

Disconnect ignitor wiring at 2 circuit plug

Disconnect and label wires from rollout switch

Disconnect and label flame sensor wire

Prepare a shallow pan to empty condensate water

Remove the clean out cap from the condensate trap and empty water

Condensate Trap Inspection and Reinstallation

Inspect the condensate trap for any damage or blockages

Reinstall the clean out cap on the condensate trap

Ensure the clean out cap is securely fastened

Turn the power back on to the furnace

Remove hoses from cold end header box

Twist and pull screens to remove

Rinse screens with tap water if needed