To begin with, let us understand what AC freezing or AC coil freezing is. In simple terms, AC coil freezing happens when water condensation on the coils collects, and the temperature drops so low that the water freezes on the unit, making it non-functional, and putting additional pressure on the compressor. It also stresses the blower fan and causes it to overheat, eventually causing complete failure in your AC unit. It makes it very dangerous for your AC unit, and you should get it fixed as soon as possible.
The system has two main types of coils: condenser and evaporator coils. Both of these are subject to freezing, and though the reasons for condenser freezing and evaporator coils freezing are similar, there are some subtle differences.
1) Evaporator coils are part of the indoor unit of the AC and are responsible for providing cool air, while the condenser coils are the heat dissipators on the outside unit of your home. Both are used for heat exchange, albeit for the opposite purposes. When the heat exchange properties of the coils are compromised due to dust settling, lack of airflow, blocked lines, or a myriad of other reasons, it results in cold air accumulating for too long, chilling the moisture out of the air and onto the coils.
2) Ac coil freezing is primarily caused by insufficient airflow. Usually due to choked air filters or some other obstruction. It doesn't let warm air circulate freely through the system, allowing cold air to let moisture condense on the coils.
3) Refrigerant leaks and lower internal pressure can also cause coil freezing as the thermodynamic equilibrium shifts towards a temperature drop, causing the refrigerant lines and, eventually, causing the AC coil to freeze over.
4) Besides these causes, there can be various reasons causing freezing, like a broken fan, blocked condensate lines, malfunctioning thermostats, and various mechanical and technical errors. Unlike other malfunctions, this can be caused by a failure in any system of the AC, which can not be diagnosed without a professional AC technician inspecting your system.
5) The most typical way to identify if you have AC coil freezing is to look for a lack of cooling, despite the AC functioning normally accompanied by a lot of moisture and condensation collected around your AC. You can then check if visible ice is forming on your indoor or outdoor coils just by a visual inspection.
6) If you suspect AC coil freezing, you should immediately shut off the system to prevent compressor failure. It would be best to give the system time to melt the ice. You can check for any leaking water or seepage that may be collecting as the ice thaws. The system needs to be unfrozen. Otherwise, the technician may be unable to work and identify the cause of the issue.
7) Before calling a technician, you can try a few basic steps to try and resolve AC coil freezing. The first is to wash and clean your AC filter and remove any dust and particulate, replacing them with new filters if required. You can turn off the cooling and set the fan to blow at max, causing air to blow over the iced coils, making the ice melt off. This only works for the indoor coil. If you have an all-weather AC, it most probably has a heat pump, you can use its defrost function.
Suppose these steps do not solve the problem. In that case, it's high time you call a trusted and qualified AC mechanic from an agency like Nakoda Urban Services to identify and rectify any coil freezing issues you might have.
The best remedy for AC coil freezing is regular maintenance to prevent expensive problems down the line, like compressor failure, that are not covered even under a warranty. It is more effective and stressful than shelling out expensive repairs and part replacements.
Nakoda Urban Services provides all the technical expertise you might need for AC service, including split and window ACs, and installation and repair for all AC-related problems, including AC coil freezing.