Portable AC Not Cooling – Fix Cold Air Problems Today!

Portable AC Not CoolingIn the summer, you may find your portable air conditioner not cooling the room the way it did a few months back.

Therefore, it is time to find cold air problems with it and fix them.

A malfunctioning AC will also raise the energy bill. In addition, the air conditioner will remain inefficient and may cause severe concerns with continuous use.

Let’s understand the common reasons that cause cooling issues and then find how to resolve them to enjoy cold air.

Many reasons can cause your portable AC not to produce the required cooling. A portable air conditioner not blowing cold may occur due to a lack of airflow or less available power.

Leaked refrigerant can be a more severe issue, requiring servicing and repair. Here are some common reasons why portable air conditioners fail to work:

No Power

The portable air conditioner may be blowing warm air. One possible cause is that the compressor is not receiving the necessary power.

Therefore, it would help to always look for power issues first, as they are the easiest to spot.

Clogged Air Filter

A clogged air filter may also be responsible for a portable AC not cooling the room. The air filter rids the incoming air of dust and other contaminants but starts clogging up after a few months.

Therefore, it can cause the air conditioner to lose its cooling capacity.

Faulty Thermostat Sensor

A faulty thermostat sensor will read an incorrect temperature value, causing variable portable AC performance.

As a result, the compressor will keep turning off and disturb the cooling cycle. Hence, it will stop cooling the room before it has reached the desired temperature.

Low Refrigerant Level

Portable air conditions typically employ Freon as the refrigerant gas. This chemical carries out the cooling cycle through phase changes between liquid and gas.

Therefore, a low Freon level will mean insufficient coolant to provide the required cooling in the space.

Related ArticleHow to Check the Freon in an AC

Incorrect Portable AC Size

Incorrect Sizing

A portable air conditioner may be blowing cold air but won’t cool the room.

This problem occurs when the unit is small and doesn’t have the thermal capacity to cool the required space.

For example, a 5000 BTU air conditioner can cool a room of around 100 to 150 square feet.

How To Fix A Portable Air Conditioner That’s Not Cooling

You can learn how to fix a portable air conditioner that is not cooling by finding solutions to the problems discussed in the section above. Here are some ways that you can use to improve your portable ACs without professional help:

No Power

You should take a multimeter and check the current levels at different components of your portable air conditioner.

Typically, you would check the primary appliance’s electricity parameters and the compressor’s power.

If the AC is plugged in but not providing power, check if the circuit breaker is in the on position. Then, please turn it on and closely listen to your portable AC.

If there is any noise, the air conditioner may have a faulty electrical component, causing cooling loss. If resetting the circuit breaker still produces power issues, you will need to consult a certified electrician.

Clogged Air Filter

A clogged air filter stops the airflow and doesn’t let it cool by passing over the evaporating refrigerant.

It would help if you had a screwdriver, detergent solution, and compressed air blower for cleaning the air filter. Here is the process:

  1. Remove the protecting casing of the portable air conditioner
  2. Remove the air filter and wash it thoroughly with the detergent solution
  3. Use compressed air to dry the air filter quickly
  4. Replace the air filter and close the protective panel

Clogged Air Filter

Faulty Thermostat Sensor

A portable air conditioner not cooling the room is often caused by a faulty thermostat sensor. It is usually placed near the filter area where the unit draws warm air.

However, you will need a replacement thermostat and the skills to put the new component in the same place.

Consequently, it is possible to damage your portable AC or affect its performance when you change this sensor by yourself.

A good practice is to call your air conditioner company’s service provider and let them replace the faulty component.

Low Refrigerant Level

The low refrigerant level will stop the portable air conditioner from cooling the required space. Remember, refrigerants don’t get used up in an AC, and therefore, a low level will mainly be caused by a leak.

You can fix this problem by thoroughly checking the unit for leaks and treating them using sealants and other methods.

As a result, you can restore the portable air conditioner’s cooling after filling the refrigerant back to the original level.

However, this problem is typically complex, and you should avoid fixing this problem by yourself.

Instead, get a trained AC specialist for this job who will use the necessary precautions while providing a long-term fix.

Incorrect Sizing

Incorrect sizing is not a mechanical or electrical problem. Unfortunately, you cannot perform any repairs to resolve portable AC not cooling.

However, cleaning the air filter and recharging the gas may improve the current situation.

The right way to solve this issue is to carefully measure the area that requires air conditioning. You will then have to order a replacement portable air conditioner to resolve this problem.

How Do I Reset My Portable Air Conditioner?

Most portable air conditioners have a reset button on their control panel. You can find where it lies on your AC unit’s manual.

If you cannot find it, you can remove the power plug and let it remain disconnected for a while. Then, it will remove all the settings and return the portable unit to its original settings.

Resetting your portable air conditioner will resolve many nagging issues.

It will remove the error displays on the unit as long as you have tackled them, like restoring the required power, replacing the filter, and ensuring a sufficient refrigerant level.

However, learning how do I reset my portable air conditioner is not a magical solution.

You will still need to ensure that all the problems are fixed, and only the control panel displays must also show that to start using the AC.

Reset Portable AC

Troubleshooting Popular Portable AC Brands

Popular portable AC brands have their characteristic issues that may require your care. Here is a short discourse on different portable air conditioners:

Arctic King Portable Air Conditioner Not Cooling

This problem usually occurs with Arctic King portable air conditioners due to loss of airflow. These air conditioners can quickly return to their regular operations after cleaning their filters.

Sometimes, you may need to replace a filter altogether to ensure optimal cooling.

Black & Decker Air Conditioner Not Cooling

A Black & Decker air conditioner not cooling may occur due to freezing coils. First, remove the protective panel when the AC is running to see if it has frozen coils.

You will need to check the unit for any refrigerant leaks, too. Otherwise, use compressed air to remove the icy deposits and let your portable unit return to standard cooling.

Haier Portable Air Conditioner Not Cooling

Haier portable air conditioner not cooling the room typically occurs due to a clogged filter. The company recommends cleaning the filter every week to ensure smooth airflow.

This recommendation works well with a unit that operates all the time, especially in a place where dust is an issue.

Hisense Portable Air Conditioner Not Cooling

Hisense portable ACs face problems due to blocked air intakes and incorrect sizing. Make sure that your room size matches well with the BTU values of your portable air conditioner unit.

Remember, a room with more windows may require more cooling than a standard room. Getting the right sized portable air conditioner will resolve this issue.

Honeywell Portable Air Conditioner Not Cooling

Honeywell portable air conditioner not cooling may often occur due to wrong settings. Read the instruction manual and ensure that the AC is in the correct mode.

Additionally, clean the air filter and check the room for any escaping cold air.

LG Portable Air Conditioner Not Cooling

LG recommends restarting the portable air conditioner by unplugging it for a few minutes. This method will reset the AC and ensure that it returns to its default setting.

First, however, always ensure that your air conditioner’s air filter is clean and provides smooth airflow.

Toshiba Portable Air Conditioner Not Cooling

Toshiba portable air conditioner not cooling is often due to lofty expectations. Remember, portable AC’s have lower efficiency and take more time to cool the same space with window air conditioners or mini-splits.

So you just need a larger capacity portable AC in most scenarios.

People Also Ask (FAQ)

Can I run my portable AC all day?

Yes, you can run your portable AC all day. Its ventilation and heating values are designed to ensure constant running. However, it would help if you gave your portable air conditioner regular breaks to prolong its life.

How can I make my portable air conditioner colder?

You can make your portable air conditioner run colder by placing it in an ideal location in the room. As a result, it should not suffer from the loss of cold air. In addition, always ensure that your air filter is clean.

How long do portable air conditioners last?

Portable air conditioners last from 5 to 10 years. You can prolong their life by performing regular maintenance and storing it properly after every use. However, their cooling capacity may decrease after some years of service.

What temperature should I set for my portable air conditioner?

Seventy-eight degrees Fahrenheit is an excellent temperature value to set on your portable air conditioner. This value will allow people to enjoy a comfortable atmosphere while not taxing the AC excessively. However, you can decrease or increase this temperature based on your comfort or ambient temperature.


If a portable air conditioner is not cooling, the problem can occur due to clogged filters, loss of power, or leaked refrigerant. Moreover, you can also resolve many issues by resetting your portable AC to its default settings.

Was This Article Helpful?

Josh Mitchell


Josh Mitchell
My name is Josh and I am obsessed with home appliances. From portable AC units to heaters and air purifiers, I enjoy testing, learning and using these devices to improve the air quality inside my family home.

My Favorite Home Appliance?

Midea U Shaped Window Air Conditioner

See Our Editorial Processes

Meet Our Team

Share Feedback