Why Does My AC Freeze Up When It’s Hot?

Why Does My AC Freeze Up When It’s Hot?

In the middle of a hot, humid Virginia Beach summer the last thing you need is for your air conditioner to malfunction. While most problems can be avoided with pre-season AC maintenance you may still experience periodic breakdowns, and as luck would have it they usually occur on the hottest day of the year. As temperatures rise your cooling system can quickly become overwhelmed and freeze up, but knowing what causes this issue can not only help restore functionality but prevent the same phenomenon from happening again next season.

What Causes an Air Conditioner to Freeze Up?

Simply put, your air conditioner cools the interior of your home through heat transference; taking the heated air from inside your home and releasing it outdoors. The process of air movement, heat absorption, and cooling involves a number of system components working together in harmony but there are a number of conditions that can disrupt this harmony and cause the unit to freeze, including:

Lack of Airflow

As part of the heating and cooling process, condensate is formed on the evaporator coil, but without sufficient airflow the temperature in the coils drops below freezing and the condensation turns to ice. Issues that can impeded the flow of air to the unit include:

  • Dirty or clogged air filter.
  • Closed or obstructed air vents.
  • Dirty or obstructed ducts.
  • Lack of return ducts.
  • Improperly sized ductwork.
  • Dirty evaporator coils.
  • Insufficient clearance around the outdoor unit.

Inadequate Maintenance

As part of annual routine maintenance, a qualified technician will inspect, tune, and clean system components including ductwork to ensure they are free of debris and in good working order prior to the start of cooling season.

Refrigerant Leak

Inadequate refrigerant levels due to an incorrect charge or coolant leak means the coils can’t absorb the required amount of heat; causing the temperature of the coolant to drop and ice to form on the coils.

Why Does My AC Freeze Up When It’s Hot?

Signs Your AC May Be Frozen

If you’re like most homeowners you don’t give your air conditioner much thought until it stops working, but due to the serious consequences that can result if ice build up continues it pays to be vigilant. Be mindful of the following warning signs and turn off your air conditioner before calling for AC repair service if you notice any of the following:

  • A sudden or drastic decrease in performance.
  • Lack of cold air.
  • Water pooling or excessive amounts of water passing through the condensate drain.
  • Reduced airflow from supply vents.
  • The air conditioner runs continuously.

While You Wait for Your System to Defrost

Once you’ve determined that there is a build up of ice on your air conditioner turn off the power to the unit to prevent further damage and allow it to defrost. While you are waiting there are a number of steps you can take to troubleshoot the cause of the freezing and prevent it from recurring including:

  • Check the air filter and clean or replace as needed.
  • Check supply and return vents in each room to ensure there is sufficient airflow, unencumbered by furniture or drapery.
  • Ensure there is a minimum of three feet of clearance around and above the outdoor unit.

Air Conditioner Repair & Replacement In Southside Hampton Roads

The skilled, experienced technicians at Mechanical Service Company will quickly diagnose the cause of your frozen AC and restore service as soon as possible. We offer 24/7 emergency AC repair in Virginia Beach and throughout Southside Hampton Roads. For efficient service any time of day or night to keep your family safe and comfortable, call us today at 757-453-5018 or contact us online to schedule an appointment.

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Keeping our customers comfortable has been our mission since day one. As a family-owned, community-based heating, cooling, and AC company in Virginia Beach, the MSCO team is comprised of certified technicians, and Trane comfort specialists with decades of combined experience in the industry.

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