How to Fix a Dehumidifier That’s Freezing Up

Dehumidifiers are usually very reliable products; however, they can be a nightmare to repair when they do fail. One of the most common problems with dehumidifiers is their tendency to freeze up. Dehumidifier freezes up is a fairly easy problem to fix and can be carried out as a DIY job.

Your dehumidifier works by removing air into its vents. The process is like refrigeration; however, rather than remaining cold itself to freeze other things, it only acts to keep their evaporator coil mildly cool.

To do this, the dehumidifier reduces the coil to a temperature below the dew point, which is the point where humidity in the air causes the liquid to condense. This process happens naturally and can be identified by sweat beads on the unit’s evaporator.

If the evaporator coil is frosting over, there will be no condensation present on the evaporator unit as the temperature will not have reached near to the dew point. This means the moisture will remain solidified as frost, which can act as a blockage against any additional air dehumidification.

Why Does My Dehumidifier Freeze Up

The most common cause of ice buildup on a dehumidifier is an ambient temperature that is far too cool for dehumidification to occur naturally. All units will come with a manufacturer’s guide that outlines the operating temperatures for these components.

Typically, dehumidifiers cannot be used when the room temperature drops below 70°F or 65°F, depending on the humidity level in the room. There are special units available on the market known as basement dehumidifiers for applications that demand such operating temperatures.

Suppose you’re operating your unit within the recommended temperatures and are still experiencing a dehumidifier freezing up. In that case, it’s likely down to one of the following:

  • Faulty/broken fan motor.
  • Air blockage within the evaporator, condenser, or filter.
  • Faulty de-icer switch.
  • Low supply of refrigerant gas in the unit.

To determine which one of the above problems has caused the frosting and ice buildup, you’ll have to do a bit of troubleshooting.

How to Troubleshoot a Dehumidifier That Is Freezing Up?

Depending on the severity of the problem, most dehumidifiers can be diagnosed and repaired as a DIY job. This saves you the time, money, and hassle it takes to call out a contractor to carry out the work for you. However, before you jump right in, you’ll need to find out where the problem lies.

Check the Room Temperature

As mentioned, the main cause of frosting is related to your ambient room temperature. If the room temperature is sitting at less than 65°F, then there’s a good chance this is the problem.

Another tell-tale sign of low room temperatures is an even layer of frost along with the evaporator coil. If this frosting has occurred locally, you can rule out room temperature as the problem. 

If you think that ambient temperature is the issue, move your unit to a higher level to check this. Warmer air will always migrate towards the top of rooms, so you can diagnose the problem accordingly by sitting your dehumidifier on a table or ledge. Another way to check this is by directing warm air towards the dehumidifier using a hairdryer or electric heater.

Check the Distance From the Wall

This is because dehumidifiers that are situated close to the wall can suffer from restricted airflow around the unit.

Check to make sure that your dehumidifier is at an ample distance from the wall such that air can move freely around the unit. Be careful not to sit your dehumidifier next to open windows or doors, as this will reduce the local air temperature around the unit and lead to the problems outlined above.

Check Your Condenser Coils

If your coils are clogged with dirt, their efficiency will be dramatically reduced. You can easily check this by unplugging the unit from the mains and removing the condenser coil to check inside. You can clean and clear any blockages and remove this problem by vacuuming around the area.

If your condenser coils are entirely iced up, then you should contact an appliance repair company to replace these parts.

However, suppose they have only partially frosted over. In that case, the problem is likely due to a lack of refrigerant fluid in the unit. Top the fluid up and check to see if this solves the dehumidifier keeps freezing up. Contact an appliance repair company or manufacturer if the issue remains as you will need these coils replaced.

Numerous potential reasons may lead your dehumidifier to freeze up. To prevent this problem and ensure the unit’s functionality, periodic maintenance is necessary.

Mas Broto

Written by: Mas Broto

Mas Broto is a small business owner with 30 years experience in the real estate industry. He is the founder and editor of, the most comprehensive free home improvement website on the planet!