“If you make a purchase using our provided links, we may receive a commission. Learn more here.
About mid-August, I start getting a lot of calls about people's portable ACs not working, or not being able to keep up.
I know that keeping cool is a top priority in the summer, and fortunately, there are a few fixes that I recommend trying before calling in the pros.
In this guide, I'll share the most common reasons why your portable AC isn't working, and their solutions.
Common reasons why your portable AC is not cooling (Plus solutions)
No power or power failure
The number one reason that the portable AC could be blowing warm air or not cooling at all is that its not receiving enough power.
I always look for power issues first, as they are the easiest to spot.
ACLAB note:
Electrical troubleshooting should always be done by a trained and licensed technician.
Solutions
The Portable AC condensation pan is full
Some newer portable AC models have an auto-evaporation feature, and you won't need to worry about condensation. However, for most portable ACs, all that condensate is directed to a bucket within the unit.
Once full, the float in the bucket has triggered the safety switch, and the unit will not run until you manually drain the bucket.
Solutions
ACLAB note:
The more you run your portable AC, the more often you have to drain it. I recommend the following steps to prevent frequent draining of the condensate bucket:
- Turn off the unit when you leave or put it on a timer.
- Shut the door. Portable AC’s are typically used in bedrooms. If you leave the door open then you are cooling the entire house and the condensation bucket will fill up quickly.
- Keep the unit’s thermostat at a reasonable setting. I’d keep mine at 75℉. Use a fan to compensate if your room doesn’t feel cool enough.
Portable AC has a 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.
Solutions
- 1Remove the protecting casing of the portable air conditioner
- 2Remove the air filter and wash it thoroughly with the detergent solution
- 3Use compressed air to dry the air filter quickly
- 4Replace the air filter and close the protective panel
ACLAB note:
Most portable air conditioners have a washable filter. I always recommend checking your user manual ahead of time, though, as some filters may need to be entirely replaced.
Faulty thermostat sensor within the AC
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.
Solutions
ACLAB note:
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.
Portable AC has a 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.
Solutions
ACLAB note:
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. Furthermore, you must carry a Section 608 Technician Certificate in order to purchase and handle any type of refrigerant.
Your portable AC is not correctly sized to the coverage area
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 small portable air conditioner can cool a room of around 100 to 150 square feet. If you have a large 600 square foot room, you will perhaps need to look into the larger dual hose portable units.
Solutions
AC has inadequate or improper ventilation
All portable ACs need to be vented. Not providing ample space for the hot air to escape will lead to the portable AC not cooling effectively.
Proper airflow is crucial for your ACs performance. If the intake or the exhaust vents are blocked then that may reduce your ACs cooling.
This also happens when users mistakenly vent out the AC into an enclosed space.
Solutions
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 at least ten minutes. This should help bring the portable AC to its default settings.
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, resetting the air conditioner is not a magical solution.
You will still need to ensure that all the persisting and underlying problems are fixed.
FAQs
Can I run my portable AC all day?
Yes, you can run your portable AC all day. Its cooling 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.
Related article: Best portable ACs with heating elements
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.
What temperature should I set for my portable air conditioner?
Seventy-five 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.
