Why Does a Dehumidifier Freeze up and How to Fix it?

Almost every house now has a dehumidifier to make the atmosphere healthy to breathe. Although most of the dehumidifier’s work, well many users face a common issue. The dehumidifier freezes up, and the reason is unknown to the users. 

If you are facing the same issue, then you are at the right place. We have done good research about the freezing of dehumidifiers, and we have found out the easiest way to fix it. 

So, let’s read more to first know all the possible reasons for freezing dehumidifiers and fixing them. 

Reasons for freezing of dehumidifier

A dehumidifier can freeze for so many reasons, but here are the most common reasons. 

1. Low Temperature 

The first reason for freezing is always a low temperature. When your dehumidifier coil is icing up, you must look at your room temperature first. 

Especially in winters when the temperature gets lower than 65 Fahrenheit, almost every machine hardly operates. As dehumidifier is already dealing with water absorption, it is very likely to freeze up. 

So, you should keep the room temperature normal or buy a dehumidifier with an automatic defrost. Otherwise, it is hard to maintain the operation of a dehumidifier in winters. 

2. Defective humidistat

The humidistat is one of the most important parts of a dehumidifier as it controls the humidity through its sensors. If the dehumidifier has a defective or less efficient humidistat, then it can cause the dehumidifier to freeze up. 

Moreover, a defective humidistat will not let the automatic defrost function, and the whole internal system will collapse. This collapse can cause huge damage to the machine. 

So, if you are keeping a normal temperature but still your dehumidifier is icing up its coils, then the reason might be a defective humidistat. 

3. Defective Bi-metal Thermostat

The bi-metal thermostat keeps the operation of moisture absorption by reading the relative humidity of the evaporator coil. If the bi-metal thermostat is defective, then there are maximum chances that the dehumidifier can freeze up. 

This defect can be a result of any wiring issues or circuit issues within the machine. Sometimes, when the dehumidifier receives a lower voltage than needed, it defects the wiring, and so does this thermostat. 

If you see such an issue, then you should take the dehumidifier to some technical expertise as the user cannot deal with it alone. 

4. Broken fan 

The fans are the essential parts of a dehumidifier in keeping the operation efficient and avoiding setting up any frost. 

Sometimes the fans can break when there is excessive dust, and the users don’t clean up the filters.

The accumulated dust particles can cause hindrance during operation, and the fan breaks as a result or stops functioning. The malfunctioning or breaking of the fan can cause the dehumidifier to freeze up. 

So, you should check that whether the fun is working or not in your dehumidifier. Usually, the fans make a whirring noise which is noticeable for the users.

5. Dirty Air filter 

Another reason for the freezing of dehumidifiers can be the dirty air filters. Sometimes the users don’t realize that the dehumidifier has air filters, and they have to maintain their cleanliness.  

The filters allow the air to pass through the internal parts of the machine, which keeps it running efficiently. The air filters are also catching the dust in the air of your house, and there is no way for this dirt to dispose of. 

When the filter is blocked with dirt, no air passes through them to reach the internal parts of the machine. As a result, the machine starts to be dysfunctional, and it might be freezing it. 

The air filters can be washable, or you might need a replacement for them. We suggest you buy a washable one as you can maintain cleanliness with them more often while the replaceable air filters put the burden on the user’s budget. 

6. Dirty Evaporator Coils 

The evaporator coils are another major part of the dehumidifiers. They also need to be cleaned up by the users on a frequent basis. Still, many users don’t pay attention to cleaning the condenser coils. 

Over time, the coils accumulate dust and other dirt particles and block the way for fresh air to pass through. This results in the malfunctioning of the machine, and it can freeze up your dehumidifier.

7. Improper ventilation 

If the dehumidifier has improper ventilation, then the machine can malfunction. The internal parts need fresh air to pass through them so they can operate better. 

The users must take care of proper ventilation of their dehumidifier. An improper ventilation results when the dehumidifier is attached to the wall with no space between. It can cause the dehumidifier to freeze up as the machine is not working properly. 

8. Electrical issues 

The electrical issues are another reason for the malfunctioning or freezing of dehumidifiers. Sometimes it is the internal mechanical issues in a dehumidifier which includes wiring, circuit, or compressor failures. 

Additionally, it can be a low-quality electrical switch that can cause the malfunctioning of the machine. A single defect in the machine or electricity or of your house can cause the whole operation to fail. 

So, you should look for a quality switch in which you intend to plug the dehumidifier as it can cause you heavy loss. 

How to Fix the Freezing of a Dehumidifier? 

Following are the simple ways through which you can fix the freezing of a dehumidifier 

1. Temperature check

As lower room temperature and cold are one of the major reasons for the freezing of dehumidifiers. So, you should keep checking the room temperature with a thermostat or thermometer. 

You should not operate your dehumidifier when the temperature is lower than 65 Fahrenheit. If it is a special model made to operate at a lower temperature, then you can use that without any anxiety. Otherwise, maintain a normal temperature in the room or turn off the dehumidifier. 

2. Proper Ventilation

Make sure that your dehumidifier is getting proper ventilation, as fresh air is essential for the machine to operate efficiently. Don’t place it too near to the walls leaving no space between the wall and the dehumidifier. 

3. Maintain cleanliness 

It is very important that you maintain the cleanliness of your dehumidifier. Clean the air filters very gently on a frequent basis, so no dirt settles in. 

The users should clean the condenser coils too to avoid any air blockage with accumulated dirt on them. This will keep your machine functioning efficiently, and there would be no icing up in your dehumidifier. 

4. Technical support

If your room temperature is fine and the dehumidifier is getting proper ventilation with frequent cleanliness, but it still freezes. The problem is mechanical or electrical, and it needs the expert’s attention. 

Never disassembly your dehumidifier by yourself, as you might lose your machine forever. It is better to approach technical support.

What to do When the Dehumidifier Ices Up or Freezes Up


The dehumidifier can freeze up for many reasons, including the user’s carelessness, low temperature, or a mechanical error. The users should maintain proper cleanliness, normal room temperature, and proper ventilation of the dehumidifier to avoid icing. 

Icing can damage the dehumidifier, and it can go useless. So, you should follow the steps mentioned above to avoid it.

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