If you live in the southern part of the United States, then it is likely that you experience some warm days throughout the fall and winter months. To help you make it through these days, you may decide to keep your air conditioner on, even if it is not always running. While this may seem like a good idea, it may be a mistake. Keep reading to learn why it may not be a good idea to run the appliance in cold weather. 

It May Void Your Warranty

Many central air-conditioning systems are expensive. Some may cost $7,000 or more. If your air conditioner is more of a recent purchase, then you may have decided to buy the warranty along with the appliance. Many HVAC professionals will provide you with a variety of different warranty plans that you can choose from. Limited warranties and basic manufacturing warranties were likely a few of your options, and you may have learned about an extended warranty as well. Even if you opted for the extended warranty that covers parts and labor when repairs are required, you still need to follow the general guidelines for use printed in your manual. If you use the AC unit in a way that the manual does not direct, then this is considered neglect on your part. 

Use guidelines usually state that the air conditioner must be used only when the outdoor temperature is within a specific range. Most manufacturers state that the temperature must be above about 60 degrees Fahrenheit. While this range is common, the lowest outdoor temperature for your cooling system may be a bit higher or lower.

Look in your manual for the lowest run temperature for your model of air conditioner and run the AC system within this range if you want to keep your warranty. If you decide to run the system anyway, and the unit breaks, then your HVAC professional will likely be able to tell that you ran the unit in cold weather based on the damage. You will then need to pay for the damages, and the warranty will likely be voided. 

You Can Break the Unit

If you do not have a warranty on the air conditioner, then voiding a warranty may not be a concern of yours. However, you should be concerned about the damage that you may subject the unit to if you run it when it is cold outside. Cold weather causes the oil that runs through the compressor pump to become thick. Thick oil will be unable to lubricate properly, and this can cause the pump to overheat and to wear significantly. When this happens, the seals in the pump may crack or break, and leaks can form. Also, thick oil may move up past the pump piston and mix with the coolant. This can cause the AC unit to malfunction.

Units that are run in cold weather also may have freezing problems where ice builds on the outside of the AC unit and also along the indoor coil. When ice builds in both of these places, then the coolant will have a difficult time changing from a gas to a liquid and back to a gas again. This means that the heat-exchange function of the unit will not work properly. The result will be wasted electricity and very little cold air blowing into your home. 

Sometimes when the copper tubing in the air conditioner is placed under a great deal of stress, the coolant lines can crack. This can lead to leaks and the need for a replacement coil. This is often an expensive repair and is best avoided. 

If you do want to use your air conditioner in the cool weather, then a cold weather add-on kit can be installed on the unit. This kit allows the cooling system to be used in colder temperatures than the AC manual stipulates. Contact your local HVAC professional to inquire about one of these kits.