The air handler is the interior portion of your central air conditioner system. The handler could exist as a standalone unit or form part of the furnace if you also have central heating. Within the air handler are several parts vital to the cooling process such as the evaporator coils and a motorized blower fan.
What does the air handler fan do, why is it vital to the cooling process, and how can problems in the fan cause problems with your overall cooling results?
Air Handler Fan Function and Importance
The air handler blower fan circulates ambient air from inside your home across the evaporator coils, which become cooled during a refrigerant phase change process, and then passes that cooled air back out the vents of your home. The rest of your air conditioning unit could work perfectly but a broken fan could keep you from enjoying any of that cooling work and can in fact result in warm air going out the vents.
Potential Malfunction: Slowed or Loose Fan Blades Circulate Little Air
The fan blades are attached to the motor with a setscrew and oscillate around a motor shaft. If that setscrew loosens, the blades can start wobbling with each turn around the shaft and that wobbling will slow down the fan speed.
Slowed fan blades will push less ambient air across the coils and less cold air out your vents. You can crank down the thermostat as low as you desire but the actual amount of cold air coming out won't change until you fix the fan blade problem.
You can usually diagnose this problem by standing next to the air handler while the unit runs and listening for clicking or clanging sound near the fan. While it isn't hard to test and fix the blower fan in the condensing unit, the air handler fan is a bit harder to access and repair. If you have any doubts on how to do the check, call in an AC repair service for help.
Potential Malfunction: Dying or Dead Motor Stops Fan and Air
Does the air handler sound suspiciously quiet and fan-free while running? Have you stopped receiving any air whatsoever through your vents while the system is running? Have you checked the surface of the evaporator coils and found the coils clean and cooled? Your air handler blower fan likely has a dead motor. Without the motor, the fan blades can't turn at all and no air will circulate through the system or out your vents.
Call an HVAC repair technician to check your fan's motor and to replace the part, if necessary, so that you can have a functioning cooling system again.
For more information contact a company like Weather Control Air Conditioning, Inc.