Before completing the following checks, turn the unit OFF and lock the main power disconnect switch open.
Disconnect all electric power, including remote disconnects before servicing. Follow proper lockout/ tagout procedures to ensure the power can not be inadvertently energized. Failure to disconnect power before servicing could result in death or serious injury.
Inspect the return air filters. Clean or replace them if necessary. Refer to the unit Service Facts for filter information.
Return Air Smoke Detector Maintenance
Airflow through the unit is affected by the amount of dirt and debris accumulated on the indoor coil and filters.
To insure that airflow through the unit is adequate for proper sampling by the return air smoke detector, complete adherence to the maintenance procedures, including recommended intervals between filter changes, and coil cleaning is required.
Periodic checks and maintenance procedures must be performed on the smoke detector to insure that it will function properly.
For detailed instructions concerning these checks and procedures, refer to the appropriate section(s) of the smoke detector Installation and Maintenance Instructions provided with the literature package for this unit.
Condensate Overflow Switch
During maintenance, the switch float (black ring) must be checked to ensure free movement up and down.
Source: MaintainX (Community Member)