Near/at end useful life, budget for replacement: The exhaust fan is near or at the end of its useful life. We recommend establishing a budget to replace the exhaust fan.
Past end useful life, budget for replacement: The exhaust fan is past the end of its useful life. We recommend establishing a budget to replace the exhaust fan.
Exhaust fan is recirculating, clean the filter at regular intervals: The exhaust fan is a recirculating type, i.e., the fan does not vent to the exterior. Clean the filter at regular intervals.