How to Fix Air Conditioner Not Cooling

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Can you imagine life before air conditioning? In cooler places where summers are short, and humidity is not a problem, it may not be too difficult to live without it. However, for most of the world and in places closer to the equator and to sea level it would be much different. There would be no way to escape the heat, the humidity, and the weakness that the two combined bring on.

It has long since been proved that too much of just about anything can be deadly, heat included. So, when you have problems with your air conditioner not cooling the air in your home or office, it can be a major pain and one that could be costly to repair. However, before you throw in the towel and call the experts here are few things you should know may save you from having to pay as much or even needing to call at all.


The Necessity of Air Conditioning 

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Air conditioning provides a way for buildings of any shape and size to stay at comfortable temperatures and humidity levels even in the warmest and wettest of climates. We can not only get out of the sun but out of the heat, it brings. This allows us to be healthier and have more energy for needed tasks. It also allows many of our household staples such as dry and canned food items, household cleaners, and even many of our decorative items to stay at temperatures that will make them last until we no longer have a use for them.

This makes properly working air conditioning units a necessity to most of us living in the developed world. When your current unit breaks or fails to keep your space cool, you immediately can tell, and it becomes a huge problem.  


What You Will Need

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If you have a problem with your air conditioner not cooling your space, there are a few things you can check out before you call the experts. Getting a basic knowledge of the main components of your AC is the first thing to do. If you end up needing to call for a repair or replacement expert, they will probably ask you some questions about your AC unit and how it is acting such as what make and model it is, what, if any, noises is it making, and what the current settings are.

So getting to know the basics of your AC unit and how it is supposed to run can help you help them what is wrong with it. Once you have this knowledge, it is easy to check various places in your home or building, as well as parts of the AC unit itself for malfunctions or problems.


Air Conditioner Not Cooling – Troubleshooting & Repairs

If there is an issue with your air conditioner not cooling, there are a number of potential causes whose repairs you can handle yourself with very little difficulty or even much prior knowledge of your specific AC unit.


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The thermostat is what controls the air temperature and settings of your AC unit. While replacing this unit and fixing malfunctions on this piece can be difficult and something an expert should handle, there are few things you can manage in regards to it. First of all, check to see if the face is blank or not. If there is no information showing on your thermostat face, then you have found your problem and will need to call a repair expert to fix it as it could be a number of different electrical issues.

If it is on and appears to be working, check to see what fan setting is being used. It may be set to “ON,” which means that the fan is continuously running whether the air is actually being cooled or not. A simple solution to this is to change it to the “AUTO” setting. This will allow your air conditioner to begin cooling automatically when air inside rises above the selected temperature of your choosing.

Outside Unit

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Your outside unit is called the condenser. It works by condensing the heat from the air that the inside unit (called the evaporator) sends to it. It needs to take in air from the outdoors to get enough airflow to do this. However, one of the common issues with your air conditioner not cooling is that the vents allowing this air into the condenser get clogged up and blocked from the outside. You will need to check to make sure this hasn’t happened.

Make sure that the grass or nature around your outside unit is not too tall and inhibiting this air flow. You will also want to clear any debris such as dirt, leaves, and twigs from vents. Simply spray the unit with a hose on a low setting to clean it and remove any weeds or tall plants from the direct path of air flow. In the future, you will want to keep that area well maintained allowing as much airflow as possible into the vents.

Inside Air Filters

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Another common problem with your air conditioner not cooling may be that the inside air filters are dirty. These filters are placed in vents around your home or building to make sure that the air passing through from your AC unit is clean and free as much dust and dirt as possible. However, over time the dust and dirt that it stops accumulate on the filter decreasing the airflow.

A good way to check and see if there is enough airflow coming through them without removing them is to hold up a lighter or flame to the vents. If the flame flickers and continues to flicker as you move away from the vent to the opposite side of the room, then your air flow is fine. The solution to not enough air flow is to replace the filters with clean air filters. You will be able to see if they are dirty or not when you remove them.

Evaporator Coils

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Inside your unit and behind your air filter are what the evaporator coils. This part of your unit is charged with cooling the air. However, these can freeze. Yes, they will freeze and literally be covered in ice. This ice prevents the air from coming into contact with the refrigerant inside the evaporator coils which stops the air from being cooled and also prevents the dehumidifying of your air. If these are frozen and covered in ice, you will need to let them thaw out. This means you will need to turn your AC off completely until they are thawed.

While the AC is off and your coils are thawed out, check to make sure that they aren’t dirty. If they are you can try to clean them gently using a soft brush and if need be a little water. However, you must be careful not to bend the fins or the coils at all. If you feel you aren’t making any progress, an AC expert will have to proper tools and experience to clean your coils properly. After they are completely thawed and cleaned, you may once again turn on your AC.


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This is not something that you can or should fix or adjust on your own, but you may at least be able to identify the signs which can save you and the professionals some time and money. The refrigerant is the liquid that absorbs the heat from your air. If you don’t have enough in your AC system, your air won’t get cold. If you don’t have enough, it means you have a leak. There are some signs you should know about in case there is a leak in your refrigerant line.

  • There will be ice build-up on your refrigerant line and outside your unit.
  • There will be a hissing or bubbling noise coming from your unit.
  • Your AC will work fine on cooler days and nights but will struggle to keep the air cold on very hot days.

Let the Professionals Do It

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If you have tried all of these troubleshooting tips with no real change in the behavior of your air conditioner not cooling, it is time to call a professional for help. They will have all the knowledge and tools to get the job done in no time. They may even be able to teach you a few more things about your specific unit you may not know or that will help you further understand the basics of how your system works.



Air conditioners are complicated and complex machines. When something goes wrong, and there is a problem or issue with your air conditioner not cooling, it can ruin your day or even your week. However, we hope that by following this advice and running through these simple tips you may be able to save yourself and your family a lot of time, money, and hassle. You may just end up being the hero of the office or your children, at least for the week.


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