It’s essential to note that the air conditioning unit is a complex piece of kit. Amongst other things, it consists of coils and coolant, both of which can be dangerous in an untrained or inexperienced hand. 

That’s why it’s advisable to have the number of a reputable air conditioning service to hand. However,  this doesn’t mean you shouldn’t have an awareness of the most common AC faults and how to fix them. Understanding these will allow you to assess the situation and decide which is the better solution, the DIY approach, or calling a professional.

Clogged Air Filters

The air filters can become clogged with dust, debris, even insects. Once they are clogged the air will not be able to flow through your unit and can’t be cooled. If left with the air conditioning unit on it can cause the unit to overheat and create an array of other problems.

The simple fix is to remove the filters. In an ideal world, you will replace them. If you’re waiting for new ones to arrive you can brush them clean, vacuum them, and even rinse them in cool water to remove the larger pieces of debris. Make sure they are fully dried before you put them back into your unit.

This is also a common cause of frozen refrigerator coils, unclogging the air filters could save you a lot of money.

Reduced Air Flow

If the airflow from your air conditioning is light then you probably have a ducting problem. You’ll need to inspect all the ducting on your unit to find the hole.

It will then be a question of whether you can cover the hoe with plastic and/or duck tape, or whether you need to replace the hose.

Warm Air Instead Of Cool

There are several reasons why this could happen but the most common is dirty condenser coils. Dirt on the coils stops the air from coming into contact with the coils properly. This reduces the effectiveness of the condenser at removing heat from the air, allowing warm air to enter your home. 

Leaving this will increase the strain on all the other parts. However, fixing it is as easy as giving the condenser a good clean. You just need a cloth and some elbow grease.


The most common noise issue in an air conditioner is connected to a defective fan. The fan is a simple bit of kit but, if left untreated it can cause the compressor to fail. Considering the cost of replacing the compressor you’ll be better off getting a new air conditioning unit.

Replacing the fan can be done by yourself but you’ll find its simpler and easier to get a professional to help you. This will ensure it's fitted properly and doesn’t place unnecessary strain on the other components of your system.

Temperature Incorrect

If the unit is blowing out cool air but the room or house isn’t getting as cold as it should be then you may have a defective thermostat. This would prevent your air conditioner from getting the right instructions and tell it to push out warm air when it should be doing cold air.