Why Do Air Conditioners Freeze Up?
As children, we were fascinated by the ice that would form on a dehumidifier or air conditioner. However, ice forming on your air conditioner is a sign it is not working properly, and in need of professional attention. Here are some of the top reasons why your air conditioner may freeze, and how to prevent it.
How Refrigerant Works
Your air conditioning runs refrigerant through its lines to help cool the air inside your home. Rather than adding cold air to the mix, this refrigerant actually absorbs the heat from the air in your system. It then transports it outside to the condensing unit, where it vents it to the air outdoors.
The way this works is by having amble air flowing through the system and regulating the pressure of the refrigerant. In order to transfer the heat outside, there must be enough of the warmer air from inside running over the evaporator coil.
The refrigerant goes through significant temperature changes as it runs through the system. Right before it passes through the evaporator coils, the pressure drops substantially, driving down the temperature. This allows the refrigerant to best absorb the air passing over the coils.
The refrigerants then pass outside to the condensing unit, where the pressure is driven up by the compressor. This intensifies the heat it absorbed from within your house, allowing it to effectively transfer to the warm outside air.
There are several problems with both circulating air and the refrigerant that can cause your system to freeze. When this happens, your system is unable to effectively cool your home and may damage your system.
Indoor Airflow Restrictions
Insufficient airflow through your system causes many problems, including system freeze-ups. This is caused by the cold refrigerant not having enough heat to absorb and warm it up. This refrigerant is then colder as it moves through the rest of the system, causing it to frost up and freeze.
One of the most common restrictions is a dirty air filter. This happens naturally as your system runs, preventing unwanted contaminants from collecting quickly further in your system.
Some contaminants do get past your filter, however, and will settle on your system’s evaporator coil and circulating fan. In both cases, this will reduce the amount of air flowing over the coil. As the evaporator coil collects these contaminants, they also act as an insulator, preventing the heat from effectively transferring.
Not Enough Refrigerant
Your system must also have the right amount of refrigerant in the system, within a small window of tolerance. Too much or too low and your system cannot work properly and this may actually damage system components.
With too little refrigerant, the system cannot pressurize properly. This causes the refrigerant to become unusually cold outside the evaporator coil, leading to freeze-ups. If there is a small leak around the compressor or condensing coil, you may notice freezing at these components.
Cooler Temps Outside
Your system is designed to run within an outdoor temperature range. If the temperature outside is too low, then it prevents the compressor from effectively pressurizing your system, leading to a freeze.
A programmable thermostat helps negate the evening drop in temperatures. You can set it to turn off the air conditioner once the temperature drops below the operational threshold for your system.
Stopping Freezes Before They Start
Once your system freezes, it may have already experienced some damage, leading to preventable repairs. The best way to avoid this is to prevent the causes of a system freeze before it even begins.
Start by changing your air filter regularly. Most experts recommend changing your air filters about every 90 days, depending on your air quality and filter type. Plan to check your filter monthly to keep a close eye on it. Consider vacuuming the intake side to help extend its useful service life.
Next, schedule your spring maintenance visit with the experts at A To Z Dependable Services. During these maintenance visits, many of the common causes of freeze-ups are addressed. This includes checking your refrigerant level, cleaning your evaporator coil and circulating fan, and inspecting your filter.
People around Niles have trusted A To Z Dependable Services for over 60 years for our air conditioning maintenance and repair expertise. In addition to air conditioning, we also provide a full range of heating and plumbing services. Give us a call to schedule your air conditioning service call and keep your system from freezing this summer.
