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Aug 7, 2023|Air Conditioner

Why Is My Air Conditioner Freezing Up?

Air Conditioning Repair in Portland, OR
Is your air conditioner freezing up? You’re not alone. This common issue leads to several comfort problems, the primary one being your AC not cooling. A frozen air conditioner can transform a balmy summer afternoon into a sweaty, uncomfortable ordeal.

Beyond discomfort, a frozen AC could cause other significant issues and costly repairs if ignored. That’s why it’s crucial to understand the causes and solutions for your air conditioner freezing up. If you’re currently facing this problem, don’t hesitate to contact First Call Heating & Cooling in Portland, OR, at 503-231-3311.

Why Do Air Conditioners Freeze Up?

Understanding why you have a frozen AC begins with acknowledging the most common causes. These include:

  • Dirty air filter: A clean filter is essential for proper air conditioner function. It allows the conditioned air to circulate freely throughout your home. However, when the air filter is dirty, it becomes an obstruction, restricting airflow. This causes the temperature of the refrigerant within the evaporator coil to drop below freezing, forming ice as a result.
  • Low refrigerant level: The refrigerant in your AC system absorbs heat from the indoor air. If the refrigerant level is low, the pressure in the AC system drops. This reduced pressure causes the refrigerant’s temperature to fall dramatically, leading to the evaporator coil becoming too cold. As a result, the moisture in the surrounding air freezes, forming ice on the coil.
  • Clogged condensate line: Your air conditioner generates condensation as it removes excess humidity from the air. This condensation expels from the system through a condensate drain line. However, the line can become clogged with dirt, mold, or algae, trapping excess moisture in the system and causing ice buildup.
  • Faulty blower fan: The blower fan distributes cooled air around your home. If it’s faulty or broken, it can’t move air over the evaporator coil. This lack of airflow prevents the refrigerant from absorbing heat, allowing its temperature to drop below freezing and for ice to form.
  • Overworked air conditioner: If your AC unit runs continually, it never gets a chance to rest, which can cause the condensation on the coil to freeze. This is especially prevalent during heat waves when the AC must run at full speed for extended periods to keep your home cool.
  • Bad thermostat: The thermostat is the command center for your AC, telling it when to start and stop based on the ambient indoor temperature. If the thermostat malfunctions, it might not send the right signals to the AC, causing it to run continuously and freeze up.

How to Prevent Your Air Conditioner from Freezing

Here are a few measures you can take to help your air conditioner run properly:

  • Change the air filter regularly: Replacing your air filter every one to three months helps air flow freely through the system. This not only prevents the coil from freezing but also helps maintain good indoor air quality.
  • Have the refrigerant checked annually: The correct refrigerant charge is crucial for your AC to cool your home. A low refrigerant level can cause freezing, but what’s more, it can damage your system over time. Regular professional servicing ensures your refrigerant levels are right on, avoiding these issues.
  • Clean the condensate line regularly: A clean condensate drain line prevents blockages that can lead to water backing up and freezing. This task should be part of your annual AC maintenance to keep the system running smoothly.
  • Ensure the blower fan works as intended: Regularly inspecting and maintaining the HVAC blower ensures proper airflow across the evaporator coil, preventing freezing. If you notice unusual noises or reduced airflow from your vents, call a professional to check on the fan.
  • Don’t overload the air conditioner: Your AC needs breaks to work efficiently. If your system runs continuously, it could indicate an undersized unit or internal problem. Seek professional advice to determine the cause and a cost-effective solution.
  • Replace the thermostat if faulty: If your thermostat is old or malfunctioning, it might be time to replace it. A new smart thermostat provides better control over your AC unit’s operation, reducing the chances of freezing.

Schedule AC Repair in Portland, OR

Your air conditioner can freeze up for several reasons. Whether the cause is a dirty air filter, low refrigerant level, faulty blower fan, or something else, First Call Heating & Cooling can set things right. We are a trusted name among Portland HVAC service providers, offering comprehensive air conditioning repair 24 hours a day. Our expert team is well-versed in identifying and addressing a broad range of cooling system issues, including your AC freezing up.

Let First Call Heating & Cooling be your only contact us at 503-231-3311 today, and we’ll make sure the summer heat doesn’t get the best of you!

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