8 Reasons Why Your Dehumidifier Freezes Up

Your dehumidifier freezing up is not normal.

Some reasons your dehumidifier is freezing up include:

  • internal components
  • fan motor
  • humidity control sensor
  • thermostat
  • the coils are dirty
  • airflow is blocked

Below you can find out exactly how to diagnose your dehumidifier freezing and how to prevent it from happening in the future.

Let’s get started.

Why Your Dehumidifier Freezes Up

1. Operating Temperature

The most common reason why your dehumidifier freezes up is that it’s being used below its optimal operating temperature.

For most dehumidifiers, it’s recommended to use the dehumidifier at 65°F or above.

If you use your dehumidifier in cold temperatures, the moisture that is removed from the air will freeze on your condenser coils.

2. Fan Motor

The blower wheel and fan blade are responsible for moving the air through your dehumidifier.

If the blower wheel or fan blade aren’t working properly, your condenser coils will freeze up.

If your filter is clean and you don’t feel any air coming out of your dehumidifier, then you should take apart your dehumidifier to check the internal coils.

Check if there is any debris that would block the airflow and then check the blower wheel and fan motor to ensure that they can move freely.

If you have a faulty fan motor or blower, then you will need to source a replacement.

3. Thermostat is broken

Some dehumidifiers have a defrost mode.

The bi-metal thermostat is responsible for sensing the temperature of the evaporator. It tells the fan to run without the compressor so the coils can defrost.

If the bi-metal thermostat is broken, then your dehumidifier will not be able to defrost your evaporator coils.

Check if the bi-metal thermostat is making positive contact with the condenser coil.

If it’s making positive contact but the coils remain frozen, you will need to purchase a new one.

You can also opt to take your dehumidifier to a professional technician for servicing.

4. Humidity or Temperature Sensor

If your dehumidifier has humidity control or temperature sensors, then it may not be functioning properly.

It works by measuring the outside humidity levels and tells your dehumidifier when to turn off and on.

The humidity control sensors must be working properly so the compressor shuts off and keeps the coils from icing over.

If the sensors are aligned with the control board, you may have an issue with your humidity or temperature sensor.

5. Air Filter is Dirty

If you have a clogged air filter, your dehumidifier will not be able to pull in new outside air which can lead to your dehumidifier freezing up.

To fix this, simply take out your filter and give it a good rinse.

Once replaced, your dehumidifier should work normally again.

6. Coils are Dirty

If your condenser coils haven’t been cleaned in a while, it can lead to your dehumidifier working extra hard and causing the condensation to freeze on your dehumidifier.

To clean your coils, you will have to take apart your dehumidifier.

The video below can help you service your dehumidifier.

7. Air Flow is Blocked

If your dehumidifier is unable to bring in new air, then it may lead to your evaporator coils freezing.

If you notice your dehumidifier is pushed up against furniture or it’s against a wall, give it some breathing room so it can bring in the fresh air.

8. Internal Components are Damaged

If the internal components of your dehumidifier are damaged, it can lead to your dehumidifier freezing up.

If you’ve checked everything and it is operating in an ambient temperature above 65F, then the internals are likely to blame.

How to Prevent Your Dehumidifier from Freezing

1. Clean your coils

Giving your dehumidifier coils a regular cleaning allows your dehumidifier to work at full capacity.

Dirty coils can cause your dehumidifier to be less efficient and cause your dehumidifier to malfunction.

2. Check the airflow

Ensure your dehumidifier has ample airflow.

If you don’t feel any air being pulled in or exhausted from your dehumidifier, it means you have a faulty fan motor or blower wheel.

Never put your dehumidifier up against any furniture or walls so it can work properly.

3. Check the temperature

Most dehumidifiers need to work in temperatures above 65 degrees Fahrenheit.

If you turn on a dehumidifier in cold environments, it will lead to the condenser coils freezing over.

To prevent this from happening, ensure your dehumidifier is rated for the ambient temperature of your environment.

During the winter months, you don’t need to use a dehumidifier unless you live in a tropical location.

4. Clean your dehumidifier

Routinely clean the outside of your dehumidifier to keep your dehumidifier working properly all year round.

Depending on how much you use your dehumidifier, you may need to clean it once to twice a year.

5. Don’t use your dehumidifier if the evaporator coil is frozen

If you find that the evaporator coils are frozen, unplug your dehumidifier and allow your dehumidifier to defrost before using it again.

Using the dehumidifier with frozen coils, it can cause the internal components to be overworked and cause your dehumidifier to malfunction.

6. Keep the air filter clean

Wash the air filter once or twice a month depending on how often you use your dehumidifier.

Cleaning the air filter will allow airflow to move through your dehumidifier and will decrease your electric bill.

7. Take your dehumidifier to a technician for repair

If you notice that your dehumidifier has an issue with the internals or has a faulty humidity sensor or defective fan motor, then you should take it to a technician if you aren’t comfortable repairing it yourself.

You can rely on our technicians to service your dehumidifier and get it back to tip-top shape in no time.

Should I Use My Dehumidifier in the Winter?

During the winter months, the cold air is likely to not be humid.

If you live in a tropical climate, then it may be that you have humid winters, but for most average winters you will not need to use a dehumidifier during winter.

How Do You Defrost a Dehumidifier?

Most newer dehumidifiers have an auto defrost feature that will defrost your dehumidifier for you. If you don’t have this feature, then it’s recommended to turn off your dehumidifier until the ice buildup melts completely.

How to Know if Your Dehumidifier Compressor is Bad?

If your dehumidifier is working above 65 degrees Fahrenheit and you can feel that it isn’t pulling any new air in, then it could mean you have a faulty compressor.

Final Thoughts

While it is normal to have cold evaporator coils, it is not normal to have ice buildup.

The most common issue with frozen dehumidifier coils is from using your dehumidifier below the recommended ambient temperature.

If you’re using it above 65 degrees Fahrenheit, then you may have an issue with a clogged air filter, broken internal components, faulty bi-metal thermostat, your coils are dirty or the airflow is restricted.

If you don’t know how to repair a dehumidifier yourself, then you should take it to a professional who can diagnose and repair the issue.

You can find repair parts for most residential dehumidifiers online.

Image Credit: Flickr.com

About Roy Cohen

Roy Cohen has a burning passion for heating, cooling, and ventilation. He aims to help you save money on expensive repairs and bring you the best HVAC products. He has years of experience behind him in HVAC repair and garage maintenance.

You can find Roy at his LinkedIn or his email: [email protected]

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