Portable Air Conditioner is not cooling ,How can this be fixed?

What’s wrong with my portable air Conditioner? Why is it not cooling enough?

Troubleshooting an appliance can be terrifying, especially during the hot summer months. Above all these events need to be addressed quickly.

To make your life easier, we have to combat service manuals and manufacturer troubleshooting guides. We have organized the guidelines that will help you find the source of your trouble depending on the way your air conditioner is behaving.

Portable Air Conditioner is not cooling, How can this be fixed?


In this guidebook, we’ll go over some steps that will help you fix the issue with your air conditioner.

Your compact air conditioner is not chilling.

If your portable air conditioner is blowing air but it’s not freezing enough, then there are a few things that can lead to such behaviour.  Here are a few things that you can consider before calling an expert.

Check the AC mode setting

Ensure your air conditioner mode is set to the right setting. Nearly all portable air conditioners have 3 settings namely Cool, Dry and Fan. Check that you have set that to Cool mode and see if it blows cold air

Investigate your thermostat temperature 

Another parameter you need to check is if your portable AC is set at a temperature that is low enough to enable cooling. For example, if your room’s temperature is 60 degrees, but your AC’s thermostat is set to 70 degrees, then the AC won’t cool.
With the help of a thermostat, set the temperature of your AC as low as it can go and see if it starts cooking

Your portable air conditioner is barely cooling

If your portable air conditioner is puffing cold but your room isn’t getting any cooler, there can be many different causes to this. Being one of the most common issues, it can be an easy fix too.

Close all doors and windows

As obvious as it may sound, close all your doors and windows when you switch on your portable AC. Open doors and windows are a pathway for warm air to come in that will nullify the effect of cold air in the room. 

Ensure you keep the doors and windows shut to minimize air transfer between your conditioned and unconditioned spaces. Even a small breach between windows and underneath doors can let cool air depart from your room.

Vent the exhaust hose outside

One of the most conventional issues of insufficient cooling from a portable AC is the leaking of the exhaust hose. The exhaust hose needs to be able to vent hot air outside your home in order for your portable AC to work adequately. If your exhaust hose is leaking hot air or is not blowing it outside then the heat that your AC is eliminating is going right back into your room.

If your exhaust hose successfully vents the heat outside, I suggest you go outside and confirm that hot air is blowing out of the portable AC from the other side. Sometimes, hindrances can block airflows such as leaves, debris, or bird nests!

There is too much heat outside.

Sometimes, it is just plain and simple that it’s too hot outside for your air conditioner to keep up with it! If the heat load coming in from external sources is way too much then your portable AC will struggle to cool your space. If you live in a space where the external temperature goes high on a frequent basis then there are 2 ways to deal with such situations, solution one is to get a larger-sized AC and the second solution ensure that your portable AC is sized in accordance with the room that you need to cool.

If your space is constantly exposed to sunlight, then there will be a drastic increase in the heat load. Places exposed to the sun get hotter than those that aren’t. 

One easy solution is to use curtains to suspend the sunlight from getting into your room. Recurrently, just blocking the sun’s heat is not enough. In this case, you’ll have to check that your portable AC is rated for more cooling than normal. 

Sources of heat load can come from within your home as well. Many electronic devices that are powered on contribute to the heat load within your space. If you are using the portable AC  to cool your kitchen, then the stove and oven will add lots of heat to your space if they’re on.

Your portable air conditioner won’t start

Is your portable AC not starting when you turn it on?

This could be due to one of several reasons:

No power to the AC unit

The main reason for an air conditioner that won’t start is that it has no power. Check to see if your air conditioner is plugged in.

Check that the outlet has power if it’s plugged in but not starting. Another thing to check is the circuit breakers. Make sure the breakers are in good working order:

  • AC’s Plugs are built into circuit breakers. Make sure they are operational.
  • If the circuit breaker in your electrical panel is not working, check it.

The tripping of circuit breakers indicates another issue.

Reset the circuit breaker and turn the AC back on. Try listening to your AC as it starts up – see if you can spot any noisy components. In many cases, an AC component malfunctions and trips the circuit breaker.

The condensate tank is full

An air conditioner also removes moisture from the air. Cool air doesn’t hold as much moisture as warm air, so water comes into the air as it cools down. 

Portable AC on cooling collects water in the tank. Some portable ACs have a pipe that drains condensate directly out of the unit. In this case, you’ll want to ensure that the condensing pipe is clear and that it drains out properly. 

Majorly this is not an issue, since the condensate tends to dissipate back into your room as your AC runs. However, water will accumulate inside the tank, particularly on hot, muggy days.

To vacate the condensate tank, you’ll need to shut off and unplug the AC from the socket board. Next, put it on a raised surface such as a stool. 

Make sure that the drain spout is hanging over the edge of the surface. Place a plastic bucket or a bowl underneath the spout. Check the used container is large enough to collect all the water that comes out of the tank of your AC. 

Nearly all portable ACs have condensate tanks that can hold about 1 litre of water, so ensure that your container can hold more than that.

Finally, open the cap on the spout and allow the water to flow out. Once all the water is out, you can replace the cap and return the AC to its initial set-up to get it up and running for use.

Few portable ACs have a bucket inside the unit that you can remove and drain out the water in your sink. Here, you don’t need to elevate your portable AC, you need to remove the bucket and dispose of the water.

Clearing the condensate tank regular basis rules out the probability of it shutting down due to  a full tank

Portable air conditioner warning lights

Portable ACs mostly send signals that let you know when their condensate tank is full. The alarm codes that your portable AC makes can be hard to decode sometimes. 

Some people find it difficult to acknowledge what their AC is trying to tell them through beeps and flashes. At such times it’s best to consult the owner’s manual for your AC to understand what the beeps and flashes mean.

Low airflow from your portable air conditioner

Occasionally, your portable air conditioner blows cold air… but not nearly as much as it usually does. In this case, it could be one of several probabilities:

The dirty air filter in portable air conditioner

A dirty air filter in your portable air conditioner will interfere with the airflow coming from your AC. Cleaning the air filter periodically will ensure that your air conditioner is getting enough airflow.

To clean the air filter: 

  1. Power off your AC. Ensure that the AC is turned completely off before taking out the air filter.
  1. Get Rid of the plastic grille that is covering the filter: Sometimes the grille gets a little dirty so clean it if needed.
  1. Take off the air filter: Be mindful to ensure that any dust or debris does not fall off the filter to the floor of your home while you take it off. You can put the filter in a trash bag so it won’t get your floors dirty while you transverse it through your house.
  2. Scrape the dust off of the filter: If the filter is slightly tainted, then you can simply dust it off to take off most of the debris.

    For really dirty air filters then you will have to rinse them out with water in your sink. Ensure the filter is completely clean and dry before putting it back into your air conditioner.
  3. The final step is to put the air filter and grille back on the air conditioner after they dry.

The fan is not blowing hard

Issues in the fan or the fan motor affect the quality of airflow Ensure the fan is at high speed for maximum airflow. Portable AC fans will have two, or even three speeds at times. If there are 2-3 speeds then they provide a button to adjust the speed of the fan. 

When the fan is on high and still not blowing as hard as it should, turn off your air conditioner and inspect the fan blade. Sometimes dust can accumulate on the fan blades and cause a reduction in performance.

If you require to clean the fan blades on your portable AC, there will likely be some segregation required. Check with your owner’s manual for guidance to do this.

Use the Fan button on the portable air conditioner to switch between high and low speed. 


The dirty coil in the portable air conditioner

In addition to the filter, there are other things that can get dirty in your air conditioner. The evaporator coil is another part that can get stained as well. 

When removing the filter for cleaning, check to see that the evaporator coil is clean. If the evaporator coil is dirty, then you’ll need to remove the dirt. 

The best-preferred option is to use a vacuum cleaner to extract the dust away. Another alternative is to blow it away using canned air, but that’s don’t recommended unless there is no other option. Plus that’s not budget-friendly. 

For the filthiest of coils, we suggest using an AC coil cleaner solution. AC coil cleaners help remove dirt, grime, and other debris from your air conditioner coils.

Frozen evaporator coil

The evaporator coil is the part that gets cold too while you are using the air conditioner. At times, the evaporator coil gets too cold, and ice starts to accumulate on it. As ice assembles, it gets difficult for air to flow through the coil.

The frozen evaporator coil on your portable air conditioner may be a warning sign for another problem. It’s unlikely for evaporator coils to freeze under normal operation, so you’ll have to check a few other parameters:

  • Inspect if the air filter is dirty. A dirty air filter will slow airflow and lead to the evaporator coil getting frozen more than normal.
  • Check if the evaporator coil is dirty. With a dirty evaporator coil, your AC will not be able to transfer heat efficiently. This causes ice to build on the evaporator coil since it is not capable of absorbing much heat.
  • The Refrigerator is leaking. If you discover that the refrigerant is leaking from your portable AC, there isn’t much you can do as a homeowner. It will take an HVAC technician with an EPA license to locate the leak, fix it, and recharge your portable AC. Oftentimes, it is more convenient to buy a new portable AC compared to getting it recharged.

Once you have altered the above, the only thing left to do is wait until the ice melts. Run the AC in fan-only mode to speed up the defrosting of ice. 

The ice build-up will eventually dissolve and the water will be accumulated in the tank or drain outside the portable AC. So do not forget to empty the tank after the ice melts completely.

Your portable air conditioner won’t stop running

Another case would be the portable air conditioner that runs… but just doesn’t stop running. Even if your room gets cold, the AC keeps working.

At such times, it’s mostly due to an issue with the control board or a sensor. Air conditioners of today use electronic controls to turn on their various components. A control board provides power to the fan and compressor through relays. If the control board has a problem, it can cause the AC to work over and over without any pause even when it is not needed.

Your portable AC’s compressor or fan may continue to run even after the setpoint temperature is reached, which may indicate an issue with the control board, a relay, or a temperature sensor.

One thing that you can try is to turn the AC off. If the compressor or fan stays running while the AC is off, then that indicates an issue with the control board or one of the relays. There is a higher chance of the sensor being damaged if nothing seems to work  

If there is an issue with the temperature sensor, it is likely to give a bad reading to the control board, causing your AC to stay running. 

  • For instance, the AC keeps running when the room temperature is 70 degrees and the setpoint temperature is 80 degrees. In this situation, the temperature sensor may be giving a false reading that’s higher than 80 degrees, causing the AC to stay running.
  • The temperature sensors, relays, and electronic control boards are all innards that are not normally user-serviceable. Check the AC owner’s manual if you find out a component needs replacement. 
  • One other thing to consider is the fact that some portable ACs will keep their fan running even after the temperature is set. In this case, try the different modes on your portable AC to see if it will stop running when your room temperature reaches the set point. Run the AC in “Eco Mode” so the fan turns off when it reaches a set temperature.