Dehumidifier Blowing Cold Air? 5 Causes & Solutions

A dehumidifier is a useful home appliance for controlling indoor humidity levels. However, when it comes to output air temperature, many people are unsure of what is normal.

If your dehumidifier is blowing cold air, there is likely something wrong with your device. The problem could be caused by frozen chilled coils, a damaged compressor, or a low room temperature. Furthermore, when the fan is turned on, the air feels colder.

I will carefully analyze each cause and guide you on how to fix it in this post. Follow it and I believe you can fix it on your own.

Is it normal for a dehumidifier to blow cold air?

No, a dehumidifier typically blows warm air instead of cold air.

If you have a compressor dehumidifier, the compressor will generate heat, and the air will be reheated before being returned to the room.

Desiccant humidifiers can produce warmer air than compressor models because moisture absorption generates heat, and the internal heater for reactivation raises the temperature of the air.

To put it simply, a dehumidifier does not normally blow cold air while dehumidifying.

What temperature should the air be coming out of a dehumidifier?

Normal exhaust air temperatures range between 70°F and 90°F. A dehumidifier can raise the ambient temperature by 5°F to 15°F, but a compressor model will not function properly if the air temperature is below 65°F.

Why is your dehumidifier blowing cold air, and how to fix it?

Even though a dehumidifier doesn’t normally produce cold air, you shouldn’t worry too much about it. You can often determine the cause and fix this issue quickly.

1. The fan mode is on 

Many dehumidifiers nowadays come with a fan or ventilating mode. My Hisense, for example, has such a mode, as shown in the image above.

When this model is turned on, the compressor stops working and only the fan continues to draw and expel air. As a result, the air will feel a little colder because it increases air circulation and allows sweat in your body to evaporate, making you feel cooler.

How to fix it?

Check if the indicator of a fan mode is green. If so, turn it off and turn on the dehumidifying mode to see if there is any change in air temperature. 

2. Your target humidity level is reached

If you can set the humidity level on the control board, it indicates that your dehumidifier has a built-in humidistat. When it detects that the room humidity level has dropped to a certain level, the compressor will automatically shut off.

Some models will cease to function entirely, while others will continue to blow air with a fan. If it is the latter, you will notice that the air is a little cold, as the fan mode is activated.

How to fix it?

There is nothing to fix. If you don’t want your dehumidifier to produce cold air like your fan, just turn it off or set it to a continuous working mode.

3. The evaporator coil is icing up, and the defrost mode is on

When we talk about a dehumidifier icing up, we’re referring to a frozen evaporator coil.

A clogged filter, dirty coil, faulty humidistat, or cold climate can cause a dehumidifier to freeze and stop collecting water.

Because this is such a common problem, manufacturers include a defrost mode in the machine to combat it.

When the defrost mode is activated, the compressor turns off to allow the evaporator coil to thaw by ambient warm air. The air from the dehumidifier will be cooler during this process.

How to fix it?

When the ice on the coils melts, the machine will return to normal operation. Some models will automatically switch to the dehumidifying mode, while others will require you to change the settings manually.

4. Damaged compressor

When the compressor is dysfunctional, it will not be able to facilitate the heat exchange process, making the air not cool down and reheat up. Similar to the situations I mentioned above, your dehumidifier turns out to be a fan under this circumstance. 

How to fix it?

If your machine is still under warranty, contact the manufacturer to see if it can be repaired or replaced. Otherwise, getting a brand one is a better option.

5. The ambient temperature is low 

Again, the compressor humidifier is recommended in an environment higher than 65°F. When the ambient temperature is low, the compressor may not be able to kick in or will have a low performance. 

Even if the humidifier can operate normally, you may still feel the air blowing out is cold since the device can’t raise the air temperature too much and the air in the room is already cold.

How to fix it?

Moving your humidifier to a warmer location, such as a room with a heater on, can often solve the problem. If your local climate is humid and cold, a desiccant model may be a better choice because it is not so susceptible to temperature changes.

Conclusion 

A dehumidifier doesn’t blow cold air normally. You should be careful when you notice the cold air coming out of your humidifier. 

Sometimes, it is because the fan mode is on or the humidity level is reached. When the evaporator is frozen, and the defrost mode is on, it will also blow cold air. A damaged compressor and low temperature can be the culprits too.

Except for replacing the compressor, you can fix this issue by yourself. 

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Liz Yang is the founder of Airsmartly. She has been working at home for a few years and realizes that the performance of the HVAC system plays such an important role in our life. She has tested a lot of products in person, like humidifiers, air purifiers, dehumidifiers, and ACs, and wants to share tips about using or troubleshooting these products with you. Her uncle is an HVAC expert with over 30 years of experience in the field, and often offers assistance when she is unsure how to handle a situation. He is also in charge of reviewing the articles on this site.

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