It may seem odd to think that an air conditioner could freeze up, even when temperatures are near triple digits outside. However, this problem is fairly common. An air conditioner works by pulling warm air into the unit and releasing cool air back into the building. Refrigerants are used to cool the intake of air and because cool air does not carry as much moisture as warm air, humidity is reduced. When a problem occurs at any point during this process, the entire system can experience a disruption in performance.
Can A Commercial AC Freeze, Even In The Summer?
It is true that a commercial air conditioning unit can freeze, even when it is hot outside. An air conditioner works by expanding the refrigerant inside the evaporator coil which forces it to cool down. However, if there is a malfunction in the system, the evaporator coil may cool the refrigerant too much causing it to freeze. There are several reasons why a commercial AC may freeze, such as blocked airflow from a clogged filter, refrigerant leaks, mechanical problems and cool summer nights.
Steps to Take When a Commercial AC Freezes Up
A freezing AC unit can be a frustrating ordeal but the problem can usually be remedied. When an AC unit freezes up, try the following:
Turn Unit Off & Let Thaw
If an AC freezes up, you will want to take several steps to quickly unthaw it before it causes damage to the system. The first step involves turning the thermostat to the OFF position and the fan to the ON position. This alone will start the defrosting process. It can take several hours for a frozen air conditioner to thaw, during which time, the AC unit needs to remain off. As the AC thaws, water will trickle into the condensate pan; it is important to make sure that the AC unit is draining properly to avoid a buildup of water in the system.
Check Unit Airflow
Sometimes an air conditioner will freeze if there is inadequate airflow from the AC unit. Weak airflow can occur for a variety of reasons, such as a clogged air filter, blocked or leaky air duct, frozen evaporator coil, or a problem with the AC blower. Inadequate airflow is usually evident when a hand is placed in front of an air vent and little to no air is being blown into the space.
Replace Dirty Filter
One of the most common causes of a frozen air conditioner is a dirty or clogged air filter. The air filter is responsible for trapping dirt, dust, and other debris that may be airborne when air is pulled into the AC unit. To ensure that the unit continues to operate at peak efficiency, it is important to replace the air filter on a regular basis to prevent a buildup of dirt. When an air filter becomes too dirty or clogged, it lowers airflow. If there is not enough warm air being blown across the evaporator coil, insufficient heat is absorbed and the coil will cool and eventually freeze. Check the air filter and replace it if needed.
Refrigerant May Be Leaking
Refrigerant is a substance used in air conditioners to help cool down the air before it is pushed back into a building. During the cooling cycle, refrigerant usually starts as a liquid, is turned into a gas, and is turned back to a liquid again. Unfortunately, refrigerants are prone to leaks which can contribute to a frozen AC unit. Some of the most common causes of a refrigerant leak include general wear and tear from age, pinhole leaks due to “formic” or naturally forming acid that eats away at the copper tubing or formaldehyde which can turn into formic acid and create holes in the copper tubes.
Could The Temperature Be Set Too Low at Night?
In certain cases, outdoor temperatures that are too low can cause an air conditioning unit to freeze up. If the AC unit is running when temperatures fall below 60 degrees, the refrigerant may continue to expand during each cooling cycle. If the air is not warm enough, the unit is not able to absorb enough heat to prevent the refrigerant in the coil from freezing. For this reason, it is important to turn off an air conditioner at night if the temperature is expected to be cool.
Call The Commercial AC Repair Experts To Take A Look
If the above steps are not effective in unfreezing the air conditioner or if the AC thaws but continues to malfunction, call an HVAC professional to diagnose the problem. To learn more about what to do when an air conditioning unit freezes or to schedule an appointment with a HVAC technician, contact the experienced commercial HVAC contractors at Cool Works Co.