Is your thermostat set correctly? A power surge or failure can reset your thermostat or turn the system off. Make sure that your thermostat is set to “COOL” and the fan is set to “AUTO”. Next, take the temperature down a few degrees so that it is set cooler than the current room temperature and wait 3-5 minutes to see if the unit comes back on. If your thermostat uses batteries, replace them now with fresh ones.
Did you blow a circuit? Your AC unit cannot run without power, so you need to look for a tripped circuit breaker or blown fuse. Your air conditioner will have two circuits: one for the indoor components and one for the outdoor unit and most homes have at least two corresponding circuits. In your electrical panel box, look for the circuits labeled AHU and AC; AHU is for the indoor unit which is typically located in the attic, utility closet or crawlspace, while AC is for the outdoor unit. Make sure that circuits are turned on by flipping each one off, then on, one at a time. If your home has a fuse box, check all fuses and replace as necessary. If the power has been off, it can take several minutes before the air conditioner comes back on.
Is your air filter clogged? If your air filter gets dirty, airflow is blocked causing your air conditioner to literally freeze up. The blocked airflow causes in a drop of pressure which leads to a drop in the temperature of the evaporator coils. Then, as humid air passes over the cold coils, it freezes. If your filters are dirty, turn the air conditioner off, replace the old filters with new ones and wait a few hours before turning the system on again so that the unit has time to defrost. You can help the process along by turning the fan to the “ON” position on your thermostat. If the unit freezes up again, the problem could be loss of refrigerant; in that case you should call your Certified Technician to add more refrigerant.
If you have addressed all these issues and the unit still is not running, it’s time to call an air conditioning professional who can diagnose the problem and recommend a course of action. Call Certified Heating and Cooling at (239) 205-8342 for a free estimate. You’ll love our award winning service and professional, skilled technicians. You might consider enrolling in our Blue Ribbon Maintenance Program. This is the best way to keep your system in top form for a low price, while saving money on future energy bill and repairs – not to mention the peace of mind that comes from never having to panic again!