What Causes Ice and Frost on Air Conditioners?

Aug 03, 2021

While your AC is supposed to be producing cold air, it is no place for ice and frost. In fact, these elements often indicate an underlying problem that can lead to major issues for your AC’s performance and the lifespan of your unit. So why is there ice on your air conditioner? What can you do about frost on your AC system? Newcomb and Company is here with insight to ensure you never have to go without cold air on a hot summer day.

Why Do I Want to Avoid Ice and Frost Build Up?

Let’s back up for a moment and answer a common question we get from customers: “Is ice on an air conditioner a problem?” The short answer is yes. When ice builds up in your air conditioner, it can cause the AC to start blowing warm air or even shutting down entirely. Ice and frost can also cause your AC unit to start using energy inefficiently, leading to high summer energy bills. Perhaps most importantly, ice and frost on your air conditioner can be the result of underlying problems. Avoiding necessary repair services can lead to premature AC system failure and more costly repairs down the road. Since you probably want your energy bills to be low and your home to stay cool, preventing ice and frost build-up is crucial. Here is a look at the top five reasons why ice and frost build-up occurs:

1. Dirty Evaporator Coils

Dirty evaporator coils are some of the biggest sources of ice and frost build-up in AC units. When an evaporator coil gets dirty, it will start to restrict your unit’s airflow. A dirty coil can also cause your AC to use more electricity than necessary, potentially resulting in compressor damage. Both of these issues can make it so your AC unit doesn’t properly eliminate humidity and moisture from the unit, with this excess humidity resulting in frost and ice.

A trained professional can fix this issue by turning off the system and cleaning or replacing the dirty evaporator coil depending on the coil’s condition. You can also prevent this issue by scheduling regular maintenance checkups, where a professional performs AC inspections on your system and cleans the evaporator coils.

2. Low Refrigerant

When an AC has low refrigerant levels, it won’t have enough pressure to perform at its best. A drop in pressure from low refrigerant can cause your evaporator coils to get too cold. When an evaporator coil is too cold, air flowing across it will start to leave moisture and humidity on it, with this moisture eventually freezing on the coil.

Since your AC system won’t run low on refrigerant naturally, an issue with your refrigerant levels will likely come from a leak. Simply adding more refrigerant into your system won’t fix the problem, as it will continue to leak out of your system. A qualified professional can find any cracks or other sources of the leak. They’ll then perform AC repairs to fix the leak and ensure your AC doesn’t see drops in refrigerant levels.

3. Blocked Airflow

Another major source of ice and frost build-up in your AC is blocked airflow. When your AC doesn’t have a consistent airflow, humidity will start to gather on the coils and freeze. One major source of inefficient airflow in an AC system is a dirty filter.

Dirty filters make it more difficult for air to pass through them, leading to greater humidity in the filter. If a dirty filter is left too long, it can become entirely clogged, preventing any airflow in your system. Homeowners can prevent this issue by turning to a company with maintenance services that will come to your home and change out filters periodically.

4. Cold Outside Temperatures

Naturally, air conditioning units are meant to cool warm air. As such, they are not designed to handle cold outside temperatures. When an AC unit runs in cold temperatures—specifically those below 60-degrees—its internal parts can start to freeze, which creates ice and frost.

Since AC units are made to handle particular temperature thresholds, it’s crucial they don’t run when drawing in colder air than what they were designed to handle.

Investing in a programmable thermostat that shuts down your AC system when the outside temperatures get too cold can help prevent frost and ice build-up. You can also prevent it manually by shutting off your AC unit whenever you see temperatures drop below 60.

5. Mechanical or Wiring Failures

Mechanical and wiring issues can cause ice to build up in your AC system. For example, a problem with writing in your thermostat or an issue with electrical contacts in an outdoor unit can cause your AC’s compressor to continue to run after it reaches the temperature you set it at. When an AC’s compressor stays on but its fans stop, the lack of airflow and the still running compressor can cause ice to form.

Besides faulty wiring, various mechanical failures can cause ice and frost to form in your system. Some common examples of mechanical issues include broken valves, blocked drains, and damaged fans. Since mechanical and wiring repairs can be dangerous work, it’s crucial you reach out to an HVAC professional trained in proper electrical safety to fix the issue.

Choose Newcomb and Company for Air Conditioning Repair in Raleigh

If you’re in Raleigh, Wilmington, or the surrounding areas, you can turn to Newcomb and Company for AC inspections and repair services. Our team will quickly spot why you might have ice and frost in your HVAC system. After we identify the source of the issue, we’ll provide appropriate AC repair services to prevent ice from building up again.

Besides responding to issues once they’ve already occurred, we can also protect your AC system from having ice and frost build-up in the future. When you purchase our comfort contracts, our team will make regular visits to your home. During these visits, our specialists will inspect your system and perform maintenance tasks to ensure your AC performs at its best.

Review our HVAC repair and replacement services today. If you have any questions or want to schedule AC service, please feel free to contact us.

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