The portable AC unit is reasonably cheap and takes up little space, making it the perfect model for cooling tiny apartments.

It is frequent among owners; why does portable AC keep shutting off? A malfunctioning portable AC, though, could disturb your sleep. If your portable AC turns off, which is frequent, it might start to frustrate you, and it is also known as short cycling.

However, since portable air conditioner issues are challenging to identify and fix, you must identify issues as soon as possible.

You might be worried and frustrated if your portable AC keeps turning on and off. We can understand your concern. Keep reading this blog; it will surely help you find the culprit so you can fix it!

Reasons Of Portable AC Keeps Turning On And Off

Reasons Of Portable AC Keeps Turning On And Off

There are various causes of short cycling in portable air conditioners. Below are some of the most likely causes of your portable air conditioner turning on and off, along with possible fixes. It is best to start with the most straightforward and clear diagnosis.

Airflow Blockage

Airflow into and out of the room must be sufficient for your portable AC. The compressor must work harder to compensate for the air loss whenever the airflow is insufficient.

Why Portable AC Fills With Water? – 5 Common Reasons
One of the common methods for chilling a room is portable, self-contained air conditioners set on the floor. Ordinary window air conditioners discharge extra moisture through the unit’s rear, where it drips to the ground.

The compressor in your unit will consequently overheat and eventually stop working. Until the compressor temperature decreases, it won't switch on.

Evaporator coils freezing is another issue that could develop due to airflow restriction. Airflow rates for evaporator coils must be specified. The coils' temperature will drop below the required level if, somehow, the airflow rate is less than the predetermined limit. Coils will freeze up if they get too cold.

In addition to moisture accumulation and airflow obstruction, another drawback of the coils icing up will be that the ice will continue to melt. The condensate pan will rapidly fill up and drip water continually.

See Also: How to Turn Off Fresh Air Intake on Air Conditioner?


Leave some room around your portable air conditioner to solve the problem. Plants, furniture, decorative items, and other obstructions should have enough space between them and your unit.

Additionally, look within the vent hose for any obstructions or solid objects. Make sure nothing outside the window or outlet is blocking the hose's open end.

Dirty Filter

A filthy filter is one of the most frequent causes of a portable air conditioner that keeps shutting off. Your portable air conditioner's air filters purify the air as it travels through the evaporator coils before being released into the room. Filters need to be cleaned because, over time, they become clogged with debris and dust.

The filter will get too dirty if it isn't cleaned. Airflow will begin to be restricted by this. As a result, the rate at which the AC releases air will slow down. After a certain number of cooling operating hours, the filter must be cleaned.

The air's quality, or the amount of dust and other particles, determines how long it takes.

The compressor will need to exert more effort to compensate for this loss. As a result, the system can overheat and shut down just before the cycle is finished. This can result in the compressor permanently failing if it continues for a suitably long time.


Filter reset indicators are found on the majority of air conditioners. It turns on whenever the filter is filthy or after a predetermined number of hours of operation. Once the filter has been removed, cleaned, and replaced, the air conditioner won't switch on until you do so.

So inspect the air filter in your portable air conditioner. The filter should be removed and cleaned.

Since air conditioner filters are virtually often washable, you won't need to replace them. Rinse the air filter carefully with lukewarm water. Before re-inserting it, give it time to dry completely.

Error In The Compressor Unit

Error In The Compressor Unit
The compressor is the most crucial part of every air conditioner using a vapor compression cycle. The refrigerant is expanded afterward to produce the cooling sensation that helps to cool your home after being pressurized by the compressor.

A failing compressor unit is another uncommon factor that could cause the machine to cycle less frequently (short cycle). The compressor will overheat and turn off if a buildup prevents the refrigerant from flowing through it. As soon as it cools down, it will turn back on. As a result of dirt and filth inside the compressor unit, the cycle will repeat itself, causing the machine to switch off continuously.

How to Drain Your Portable Air Conditioner? - DIY Hacks
One of the most convenient ways to keep the environment of your home cool is to install a portable air conditioner. These air conditioners maintain the temperature at best without requiring troublesome installation.


If so, you can choose between replacing it and repairing it. Call a licensed AC expert to fix this issue for you in any scenario. The air conditioner's compressor is the costliest part to replace or fix.

Determine whether it is cost-effective, considering the worth of your current portable AC, before making a choice. Usually, purchasing a new product is preferable.

Condenser Coils That Are Clogged

Condenser coils that are clogged or constrained may be the cause of your portable air conditioner turning off. The refrigerant must be kept in liquid form, which is done by the condenser coils.

Condenser coils that are blocked will work much harder. And the condenser begins to overheat when it has to work harder than before, which leads to short cycling.


Most portable AC units make it simple to resolve this issue. For you to easily clean the condenser coils, manufacturers typically provide easy access to them. But if you don't have access, it will be a little trickier, but you can do it. Clean the coils softly by moving the brush up and down and side to side.

This cleaning will prevent the AC from cycling short. You are also recommended to clean the condenser coil once a year, and avoid making the AC stay near any plant.

Insufficient Refrigerant

Vapor compression is the cooling method used by portable air conditioners. The refrigerant travels through the AC system's pipes and is never reduced. The refrigerant's only function is to continue changing liquids into gasses to produce the cooling effect.

The leakage in the pipes is one of the main reasons for dropping the refrigerant level. An air conditioner must keep the required refrigerant level to operate properly regardless of how long the air conditioner is on. Low pressure and this leakage can cause the system to turn on and off frequently.


Finding the source of the leak is the first step in fixing the issue. There may be a leak in the same location if your portable air conditioner took a hit somewhere or if you notice a bend. After identifying and repairing the leak, slowly add small amounts of refrigerant to that line.

It is better to ensure that your refrigerant is appropriate for your portable air conditioner. Recharging your portable air conditioner takes practice and is not very simple. If you don't know how to do it, call a professional.

Problems With Electrical Wiring

Electrical wiring can be one of the reasons for continuously shutting on and off your portable air conditioner. When it comes to a portable air conditioner's electrical system, two issues can arise.

Wiring issues or defective electrical components, such as a capacitor or relay, could be to blame.

Check the wires thoroughly to see if they are okay. If the wires are working fine, the capacitor must be wrong, causing the AC to turn on and off constantly. Your air conditioners will not turn on if the relay is at fault.


You won't need to spend much money to solve this issue because electrical components are typically quite affordable and easily accessible. Replace the wiring if they are the culprit. Contact a technician if you have no experience with changing the capacitor or relay.

Power Supply Issue

A constant power supply is required to operate the system correctly. Any disturbance in it can cause your portable air conditioner to shut off without giving any warning signs.

The plug is the first thing you need to check if the portable AC is shutting off. An incorrectly plugged unit can cause this issue.

If everything is going with the plug, you should have to look to see if the system is receiving good power from the socket. An unstable power supply can also cause short cycling.


Plug the switch of the AC if you feel that is the cause of it. But if the wall socket is the issue, you need to plug it into another socket or change the old one. And if these things are going well, there must be some internal damage. Fix it as soon as you can.


In this blog, we have presented some potential causes of short cycling. It is difficult to identify the thing causing the issue; if you have found it, fixation is simple.

Most of them can be fixed at home, but contact a professional if you feel it is impossible. We hope this article will help you identify and solve it. So, fix your portable AC as soon as possible and enjoy your summer in a cool and comfortable room!

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