Why Is My AC Freezing Up?

It always seems to happen that when you need it the most, your AC gives up the ghost. The typical residential AC system has to work harder when outdoor temperatures are sky-high, increasing the chances that it may malfunction.

One of the things that can go wrong is that the system freezes. And, when summer temperatures are soaring, the last thing you need is for your AC system to freeze up and stop functioning correctly.

The main explanation for this ice buildup lies in a cold substance within the air conditioner called refrigerant, which travels through the system to absorb heat from your air. When the refrigerant doesn't have enough warm air balancing it out, it will ice over the system. Then, the AC will blow warm air or stop working entirely.

Why has the refrigerant frozen over your AC system? The following common scenarios explain why:

• Clogged air filters
• Blocked return vents
• A dirty condenser unit
• Refrigerant leaks

Most people don’t think that their AC unit is going to freeze up during the middle of a heatwave, but this is far from an uncommon scenario. Keep reading to learn more about the scenarios listed above.

Is Your AC System In Danger of Freezing or Already Partially Frozen?

Don’t wait until a sweltering summer day to find out that your air conditioner isn’t working. Our NATE-certified technicians at Four Seasons can inspect your system, make necessary AC repairs, and ensure it’s good to go. Call us at ​​503-538-1950 today, or request an appointment through our online portal.

Various household particulates can clog air filters, including everyday dust, pet dander, pet hair, and pollen. Once an air filter clogs, it limits the warm airflow coming into the system and blowing over the evaporator coil. Why is this a problem?

The evaporator coil hosts the frigid refrigerant. Without warm air blowing over the evaporator coils, the refrigerant becomes increasingly cold and freezes your coil, indoor unit, then spreads the ice to other parts of the air conditioner if the situation isn’t remedied.

Not to mention that dirty air filters can’t trap particulates like mold spores as well as clean ones. The particulates circulate throughout your home, contributing to a significant decrease in indoor air quality.

Air filters need replacement an average of every three months in most households. However, if you’ve got multiple indoor pets in your home or have household residents who are sensitive to allergens, you may need to change them with greater frequency (i.e., every month). Call Four Seasons if it’s time to install a new one. We can complete a full air conditioner tune-up in less than one hour, including replacing a dirty filter.

Blocked return air vents are similar to clogged air filters in that they limit the amount of warm air that blows over the condenser coils and cause the temperature of the refrigerant to drop. Nearby furnishing, draperies, and damaged ductwork can obstruct return vents. However, unlike clogged air filters, blocked return vents have a noticeable tell. You’ll notice an abrupt decrease in cool airflow throughout your household.

There will be several return vents situated throughout your home. Inspect the area near the vents to ensure that a piece of furniture or a pair of draperies have not inadvertently blocked them. Keep the air vents open—even in unused rooms.

Dirty condenser coils on your outdoor AC unit are culprits for a frozen air conditioner. Dust and debris create buildup and essentially suffocate the coils. To make matters worse, mold spores are usually part of the picture when condenser coils are dirty. Even though the condenser is typically situated in a sealed compartment on the home's exterior, dirt and debris buildup happens naturally over time.

For the condenser unit to be as clean as possible, keeping the outdoor area around it free of weeds is important. You should also cut back any overhanging trees and shrubs and vacuum the area with an outdoor vacuum to remove loose debris near the unit.

Cleaning condenser coils themselves is a job best left to skilled professionals as they are delicate. If mold colonies are present, their removal will require special handling from specialists. Because buildup on your condenser coils is inevitable, cleaning them should be a part of your unit’s regularly scheduled maintenance. Our trained technicians at Four Seasons can thoroughly clean your coils to keep your AC system in top condition

When refrigerant levels in your AC system are low, the interior pressure drops, creating an icy environment as the refrigerant expands. So, then, the rest of the refrigerant in the outdoor refrigerant lines and the coils freeze up. Your first instinct may be to want to add refrigerant, but technicians cannot do this. Because refrigerant levels don’t naturally reduce in time due to their closed-loop system, diminishing refrigerant indicates a leak in the AC system.

One of the main signs of a possible leak is a sudden spike in utility bills without a corresponding temperature change. If you suspect that the refrigerant levels in your AC unit are lower than they should be, turn the thermostat off to prevent further damage. Call Four Seasons for a thorough inspection to ensure your home remains cool and comfortable this summer.

Refrigerant leaks are a job for professionals, as they are toxic and require special training and equipment.

Are you experiencing higher-than-usual electric bills, or is your home simply not staying cool when outdoor temperatures soar? You frequently ask yourself, “Why is my AC freezing up?”

If so, call Four Seasons for honest, old-school service. We’ve provided homeowners in Portland and the surrounding areas with 5-star air conditioner repairs since 1979. Call us today at 503-538-1950. You can also use our convenient online portal to request a same-day service appointment.