If an air conditioner's outside unit stops running while the inside blower continues to run, and then the cooling ability returns after turning off the breaker switch for a few minutes, it is likely due to a frozen evaporator coil.
Here's what happens in this scenario:
Frozen Evaporator Coil: The evaporator coil is the part of the air conditioner located inside the indoor unit. Its function is to cool the air as it passes over it. However, if there is restricted airflow or low refrigerant levels, the evaporator coil may get too cold, causing condensation to freeze on its surface.
Continuing Inside Blower: The inside blower keeps running even if the outside unit is not operational. This can cause the air temperature around the evaporator coil to drop further.
Lack of Warm Air: The outside unit is responsible for transferring heat from the indoor air to the outside. When it stops running, warm air is no longer being pulled from the indoor air, which exacerbates the freezing of the evaporator coil.
Turning Off the Breaker Switch: When you turn off the breaker switch for a few minutes, the inside blower stops blowing cold air over the frozen evaporator coil. This allows the coil to thaw partially, and any ice that has built up starts to melt.
Cooling Returns: After turning the breaker switch back on, the air conditioner initially cools effectively because the melted ice increases airflow over the evaporator coil. However, if the root cause of the freezing is not addressed, the problem may recur.
Common reasons for a frozen evaporator coil include:
A. Dirty Air Filters: Dirty air filters can obstruct airflow, leading to inadequate heat exchange and freezing of the coil.
B. Low Refrigerant Levels: Low refrigerant levels can result from leaks in the system. When the refrigerant is insufficient, the coil may get too cold and freeze.
C. Faulty Components: Malfunctioning components like a faulty blower motor, expansion valve, or thermostat can cause improper operation and contribute to the freezing of the evaporator coil.
If you experience this issue, it's essential to have a professional HVAC technician inspect your air conditioning system to diagnose and fix the underlying problem. Continuing to run the air conditioner with a frozen evaporator coil can cause damage to the compressor and other components, leading to more extensive and costly repairs.