How To Recharge A Dehumidifier? A Complete Guide

More and more people choose to run a dehumidifier at home since it is effective in solving moisture problems. 

Over time, the performance of a dehumidifier can degrade, and many people wonder if it needs a recharge. There are a few types of dehumidifiers available, and only two of them are rechargeable. 

This post will provide all the information you need about recharging a dehumidifier at your fingertip so that you can understand whether or not you should and how to recharge a dehumidifier. 

Which type of dehumidifier is rechargeable?

As I mentioned at the beginning, not every type of dehumidifier needs recharging. In general, rechargeable dehumidifiers include refrigerant dehumidifiers and rechargeable desiccant dehumidifiers. 

The working principle of the refrigerant dehumidifier (also known as a compressor dehumidifier) is similar to that of the air conditioner. It makes use of coolant, which circulates between the evaporator coil and condenser coil. 

The coolant will release heat and convert vapor to liquid when it flows through the condenser coil. When it flows through the evaporator coil, it will absorb heat and convert liquid to vapor. This explains why the moisture in the air can be condensed out when passing through the evaporator coil. 

Coolant can be decreased due to leakage. The performance will be affected when there is less coolant in the system. That’ why you need to recharge it in some cases.

Unlike compressor units, rechargeable desiccant dehumidifiers don’t utilize coolant and are non-electric. They consist of a moisture-absorbent chemical material that can naturally absorb the air’s moisture. 

When the material has absorbed sufficient moisture, it will turn to another color, indicating that it needs a charge. Putting it in a microwave or plugging it in an outlet for a while can make it usable again.

When should you recharge a dehumidifier?

As for rechargeable desiccant dehumidifiers, it is easy to identify when to recharge it. Once the beads change color, it is time to give them a charge. 

However, things can be more complicated when it comes to recharging a refrigerant dehumidifier. Several signs indicate your device is low in the coolant. 

Much less water collected

Every dehumidifier can collect a certain amount of water per day. If you find the machine continues to work but collects much less water than usual, if the outdoor humidity level doesn’t change much recently, it may be due to the lack of coolant.

Humid air

When the machine drains the water through a hose, it is hard to make a judgment through the collected water. Don’t worry. You can identify it through the air that is vented out.

When the machine doesn’t have sufficient refrigerant, it cannot condense too much water vapor out, making the air coming out of it still moist.

Humidity level doesn’t change 

Another way to check if your dehumidifier needs a recharge is to monitor the hygrometer. When the machine keeps working, but there is no change in humidity level, it is a sign that you need to recharge it.

However, recharging a dehumidifier could be costly. If you have used your dehumidifier for a few years, purchasing a new one could be a better choice. 

Can you recharge a dehumidifier on your own?

No. According to laws in many states, you can’t recharge a dehumidifier on your own unless you have the license required. 

This is because many kinds of coolants are dangerous which can pose health risks to human beings and the environment.

While some old models can be recharged easily, we don’t advise you to do that even if you can get the recharge kit required. 

Remember to contact a legal HVAC company or professional if you insist on doing it.

Which refrigerant should you use?

Depending on which model you have, the common refrigerant includes R-12, R-22 and R-410A.

Few dehumidifiers use R-12 these days because it is very dangerous. But dehumidifiers that were made before 2010 may use R-22, which is also called Freon. R-410A is more efficient and safer, which will also cause ozone destruction.

How to recharge a dehumidifier?

Even though you are not allowed to recharge a dehumidifier by yourself, you can still try to understand the basic steps of how to do it. 

Step 1: Purchase a recharge kit that is compatible with your device. 

Step 2: Unplug the machine.

Step 3: Disassemble the dehumidifier. 

Step 4: Remove the dust and dirt on the coil

Step 5: Connect the coolant with the compressor as per instruction. 

Step 6: After the compressor gets charged, disconnect it from the coolant. 

Step 7: Put everything back and test the machine again.

If recharging doesn’t work, what to do?

Again, you should fix the leaks before recharging. Otherwise, the coolant will continue to lose. 

Beyond that,  you should also douche check the condition of the fan and motor to see if there is something wrong. 

How to avoid recharging a dehumidifier frequently?

Not every dehumidifier will need a recharge. The best way to avoid it is to maintain your device regularly. 

Placing your device in a proper room is important. Putting it in a big room can be overloaded because it can’t lower the humidity to your target level. In this case, the coils will ice up and break, causing leaks gradually.

Cleaning the dehumidifier is also crucial. Cleaning the bucket and replacing the air filter regularly can keep the machine in a good state.


This post has illustrated the most important information you need to know about recharging a dehumidifier. While you can’t recharge it on your own according to most local laws, you can have a basic understanding of how to do it anyway. 

Remember to maintain your device regularly so that you can avoid recharging it. 

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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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