Why Your Dehumidifier Freezes Up (And How To Fix)

Dehumidifiers work to remove excess moisture from the air in a home but as with many other appliances they need to be used within a certain range of conditions in order to operate efficiently.

A dehumidifier that’s freezing up can be one of the main problems associated with not using a dehumidifier within this optimal condition range.

A dehumidifier can freeze up if the room temperature is too cold, typically below 41 degrees Fahrenheit (5 degrees C). Other reasons for a frozen dehumidifier can include faulty fans and sensors, a dirty air filter, and bad airflow through the machine.

Understanding how your dehumidifier is supposed to work, and knowing the reasons why it’s not, can help you find a solution to the issue of it freezing up.

We found that our dehumidifier was performing poorly due to dust and dirt build up on the air filters, but there can be other factors that can cause a dehumidifier to freeze up depending on the local conditions.

Dusty air filter

Read on to discover all you need to know about a dehumidifier that freezes up.

How A Dehumidifier Should Work

Humidity in the air can cause a lot of issues, especially in a basement. Whether your basement is finished or not, excess moisture in the air can be a cause for concern.

The extra water content in the air can make everything feel damp. Moreover, it can cause mold, discolorization, and other problems.

A dehumidifier removes that excess water from the air.

If you’ve found that your dehumidifier is no longer properly removing the water from the air, then its coils may be frozen. So, how is a dehumidifier supposed to work?

  • A dehumidifier will take moisture from the air and turn it into water droplets.
  • The water droplets will drop down into a bucket.
  • When the bucket is full, the dehumidifier will turn off, and you must empty the bucket.
  • A dehumidifier will not cool the air that it’s maintaining.

While a dehumidifier works almost the same way as an air conditioner, it will not cool the air outside of it.

However, a refrigerant form of dehumidifier does have cooling coils that turn the water content of the air into the water droplets, thereby removing excess moisture from the air.

Since there are cooling coils within refrigerant dehumidifiers, there is the possibility of them freezing up.

A refrigerant dehumidifier, that may freeze up if used in very low temperatures

Not all types of dehumidifier will freeze up, however.

Refrigerant dehumidifiers, which use coils to remove moisture from the air, can typically work down to around 41 degrees F, but this can depend on the model.

Desiccant dehumidifiers, which use absorbent chemicals such as silica gel rather than coils, may not freeze up at all until much lower temperatures.

For example, the manual to our own desiccant dehumidifier explains that it can be used effectively within the range of 34°F (1°C) and 90°F (31°C).

Dehumidifier Plugged In
Our desiccant dehumidifier, which can be used in lower temperatures if required

Reasons Why A Dehumidifier Freezes Up

If your dehumidifier is not working properly, it may be frozen.

Understanding the reasons behind why a dehumidifier freezes up can help you to figure out how to fix it and how to help prevent it from occurring in the first place.

Consider the following reasons why the dehumidifier you have may be freezing up.

  • The air temperature is too cold. Most dehumidifiers can operate in temperatures down to around 41 degrees Fahrenheit or 5 degrees Celsius (GE Appliances). For many, this is not an issue because they use their unit mostly in the summer months. If the room temperature is too cold, it can cause the dehumidifier to freeze.
Dehumidifier Controls
A dehumidifier may be able to display room temperature
  • The air filter is too dirty. You’ll need to replace and/or clean the air filter of a dehumidifier regularly to help prevent the unit from freezing up. When the air filter gets clogged with dirt and dust, it can compromise the airflow. This will lead to the coils freezing up because there isn’t sufficient air circulation.
Dust building up on our dehumidifier
  • The condenser coils are too dirty. Likewise, the condenser coils may also be too dirty. Dirty condenser coils will also interrupt proper airflow, which will lead to the coils freezing up. It is important to note that even if the air filter is clean, some dirt and dust can make it to the coils, so it is important to monitor them.
  • The fan motor may be faulty. For the fans to work, the motor needs to be in good, working condition. When it is not, the fans will not work, which will lead to improper airflow. The warm air needs to be constantly moving because if it does not then the unit may begin to frost.
  • The fan may be broken. Possibly the fan itself is broken. This is why it is important to regularly check the working components of your dehumidifier to make sure everything is properly working. If the fan breaks, the airflow will be interrupted, which can permanently damage the appliance.
  • The frost detection sensors are not working. Many dehumidifiers have sensors that monitor the frost buildup inside the unit. When it detects that frost is building up, it will automatically shut off the unit. However, if the sensor is broken, this safety feature will not work, which can lead to it becoming completely frozen.

Airflow is one of the most important factors when considering a dehumidifier that freezes up.

If the airflow is not constant, it can lead to problems. You should therefore periodically check all the working parts of a dehumidifier to help prevent it from freezing up.

How To Fix A Frozen Dehumidifier

Dehumidifiers may freeze from time to time.

Consider the following solutions when you discover that your dehumidifier has begun to freeze from use.

  • Clean the air filter. The air filter is important to maintain. You can easily clean the air filter by removing it and cleaning it with soap and water. Be sure to use a cloth or sponge. You don’t want to use anything that is abrasive on the air filter. Once it is completely dry, you can reattach it.
An old and new air filter
  • Monitor the air temperature. If you find that the air temperature is to blame, try to turn the thermostat up to whatever the minimum temperature the unit can handle. If you cannot change the air temperature, you may need to get a special dehumidifier that can work in very cold temperatures.
  • Replace the fan. If the fan is broken, it is possible to replace it. Make sure, however, that the fan is clean and the motor is clean. When these components are dirty they can work improperly. If they are clean, but the fan still does not work, it may be time to replace the fan.
  • Defrost the coils. When you see that ice has formed over the coils, you should turn the unit off and let the coils completely defrost. Additionally, it is best to avoid using the dehumidifier for a short period before restarting it.
  • Call a technician. If the issue is electrical, or you are not comfortable replacing certain mechanical parts, you should call a technician who will have the expertise to fix your dehumidifier.

If the issue is not resolved by cleaning, replacement parts, or a technician’s expertise, then it may simply be time to get a new dehumidifier.

Remember, proper maintenance done regularly will help prolong the lifespan of your dehumidifier and keep it working efficiently for a long time.

Should You Use A Dehumidifier That Freezes?

If your dehumidifier freezes and you can fix it, then it is okay to keep using it. The issue arises when the dehumidifier keeps freezing.

Repeated freezing of the coils can permanently damage them.

When the unit is not working properly, it will try to overcompensate for the frozen coils. This can lead to your dehumidifier burning out. Moreover, a dehumidifier that keeps freezing is a sign that something is wrong with the internal mechanisms.

When troubleshooting does not work, it is best to either call a technician or to get a new dehumidifier. You’ll want to make sure you have a properly working unit as soon as you can.

Why Does A Dehumidifier Freeze Up?

A dehumidifier may freeze up due to several reasons, such as the air temperature being too cool, the air filter being dirty, or the coils being dirty.

It’s important to monitor the functionality of your dehumidifier. If you perform proper maintenance on your dehumidifier, you shouldn’t have any issues. However, if the dehumidifier does freeze up, it’s possible to fix it at home, either by leaving the coils to defrost or fixing another issue.

Always check the conditions that your particular model of dehumidifier is able to work within, such as the minimum operating temperature.

Further Reading

Do Dehumidifiers Lose Effectiveness?

Do Dehumidifiers Blow Hot or Cold Air?

When Should I Turn Off My Dehumidifier?

Do Dehumidifiers Need Ventilation?

Do Dehumidifiers Contain Freon?