Air Conditioner Freezing Up

The air conditioner (AC) is a unit, which, like a refrigerator cools an environment, though on a larger scale. The air conditioner uses the phase conversion process as a working principle. The process dictates that when you convert a liquid into a gas, it absorbs heat. The liquid used for this unit is the refrigerator charge. Once the hot air in the room moves across the cold evaporator coils, the refrigerator charge absorbs the room heat as it changes phase from a liquid to a gas. The AC unit then uses a compressor to convert the charge back into a liquid state by compressing the gas, a process which increases the temperature and converts the gas into liquid. The condenser and fan transmitted this excess heat to the outdoors. This causes the gas to cool, and the cycle starts all over again.

There are various explanations why an air conditioner freezes. You might need to call up HVAC service technicians to repair the problems. They include low refrigerator charge, outdoor temperature and inadequate airflow.

Low Refrigerator Charge

Below normal refrigerator charge amount can cause an AC to freeze up. Typical reasons that generate low charge include a leak in the lines or maybe a pinched duct, which can restrict flow of this charge. Substantial vibration of the lines or rubbing against other components, which causes the line to wear down, can cause the leaks. Recently repaired joints may also be sites of leakage due to improper soldering. To fix this problem, you need to inspect the refrigerant lines to check for leaks and then fix them. In case no leakage is found, just top up the charge.

Outdoor Temperature

When the outdoor temperature falls under 60 degrees, most units tend to fail to function properly and freeze up. The answer is to switch off the unit up until the temperature increases, open the windows or have a HVAC service technician install an ambient temperature regulator unit in the system.

Insufficient Air Flow

Clogged air filters, too small air ducts and slow fans can cause insufficient airflow. The rate of airflow can be so minimal that the entire system freezes up. To ensure that this doesn’t happen, clean the filters regularly and replace them once each year. Also, call up a trained HVAC service professional to examine and replace the undersized ducts and slow fan.