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The system will not run at all, what do you think?

The most common reason that a system will not run is because of a loss of power. In most every situation an air conditioning system is protected electrically by a breaker or fuse which is located somewhere in the power supply lines upstream from both the air handler and condenser units.

This breaker is designed to provide over current protection and prevent electrical damage to your equipment.

Find this breaker, turn it completely "off" even if it appears to be "off", then turn it back on again. If it trips again, leave it alone and call your contractor.

The second most common reason for a system not to respond when called for, is problems in the low voltage (24v) control circuit. This circuit is comprised of the controllers and relays that send signals to the components in your system to perform specific functions like heating, cooling and fan only.


The most common problems are found in the thermostat connections and with failure of the transformer. If you are mechanically inclined, you can change your thermostat yourself in most cases because the various wires coming to your thermostat are color coded and you simply hook up the appropriate color wire to the terminal for that color on the thermostat.

And, don't forget! Dirt is the biggest enemy of your air conditioner! Giving your air conditioning system an efficient, high MERV rating air filter is the best thing you can do for your air conditioner. A good air filter will extend the life of your air conditioner because the important parts, like the blower assembly, the cooling coil, and other inner parts will stay cleaner, operate more efficiently and last longer.

And, as a side benefit of having a good air filter, your family and you will enjoy breathing much healthier indoor air. Air that will be free of dust mites, mold, mildew, dust, pet dander, etc. etc.