Take Care of Your “Sick” Air Conditioner

July 28, 2011

Being sick is no fun! Thankfully we all have remedies to make ourselves feel better. Your air conditioning system can also become “sick” (not running well or at all). Below are some signs that your air conditioner is “not feeling well” and some possible remedies.

Air conditioner doesn't turn on. First, make sure your thermostat is set on “cool” and well below the room temperature. Next, check to see if a breaker is tripped or a fuse is blown. Check to see if the furnace power switch is turned on and that the outdoor condenser unit's power switch hasn't been shut off. Also, check to make sure the 240-Volt disconnect next to the compressor (located in a metal box usually mounted to the house) hasn't been shut off. If your air conditioner is still not turning on, contact a professional technician.

Air conditioner isn't cooling. If your air conditioner is running but not cooling, it may just need to be cleaned. Here are some easy steps you can take. First, check and change out the air filter if it's dirty. Rake leaves and debris away from the outdoor condenser and trim any bushes that might block airflow. During an annual tune-up your technician can complete a more thorough cleaning of your system.

Constant On and Off Cycling. If your system shuts off before the room is at a comfortable temperature, it may not be cycling enough air through the thermostat to take a representative sample. The thermostat may need to be recalibrated. A clog in the evaporator unit or something blocking the fan can also cause this constant cycling. Contact a professional technician.

Leaky air conditioner. A great benefit of air conditioners is that they remove humidity from your indoor air, however, during this process they create significant condensation. This excess condensation exits through a plastic drain tube that goes into the floor drain or is carried away by a small pump. If there is water pooling at the base of your unit, something may be blocking the water's flow or the pump may not be working. If the tube is leaking it needs to be replaced. Ice may also be causing a block in the tube. If this is the case, check to see if you have a dirty filter. If the filter is fine, your refrigerant is probably low. Contact a professional technician.

Loud wailing noise from air conditioner. This is a common complaint and is generally caused by a dislodged fan belt, which just needs to be put back on. It can also be caused by the bearings in the motor, which may need lubrication or replacement. Contact a professional technician.

Frozen Coils. Frozen coils and ice can block the operation of the unit, creating something like a bottleneck when there should be a circulating combination of Freon and air. Often a calibration check can eliminate this problem altogether. Contact a professional technician.

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Last Updated: June 09, 2023