Category - Air Conditioning
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Nils Berg

31 Jan : Updated 12 Apr ● 4 min read

What is an air conditioning condenser unit?

Many of us depend on our air conditioning unit to keep cool throughout those hot months, but what actually goes on behind the scenes? It is extremely beneficial to know what your air conditioning condenser unit is and its role in your A/C system, so that you can maintain it properly and understand how to fix any issues if they occur. This helpful guide from BOXT, will help you do exactly that. 


So, what is a condenser unit? 

An air conditioning condenser unit is the outdoor part of your system. The outdoor unit contains the fan, the condenser and a compressor. Both the indoor unit and the outdoor unit are required to work together to provide cool air to the rooms of your home. 

The condenser is the most vital part of the outdoor unit. The condenser coils are made out of copper. Within the condenser, there are a series of fans with aluminium fins. 

The compressor, an electric pump, is also an important part of the outdoor unit as it pressurises the refrigerant, a cooling agent, and transfers it to the condenser coil. 

What is the role of a condenser unit?

The outdoor unit, also known as the condenser unit, houses the compressor. The refrigerant gas enters the compressor where the molecules are compressed and become very hot. The compressor then sends the refrigerant gas to the condenser where the fans work to remove the heat from the refrigerant. The refrigerant becomes a liquid and then returns the refrigerant to the indoor unit for it to do its part. 

When the indoor unit has collected the heated air, it is sent back to the outside where it is disposed of.  This process is repeated until the air in your home reaches the temperature that you set on the thermostat. 

So, that’s the role of the condenser unit. The role of the actual condenser within it is to pump the refrigerant and cool it, converting it into liquid form. Without it, the system is useless.

Issues with your A/C condenser 

Sometimes things can go wrong. Spotting the issues at an early stage can save you money and stop your air conditioning system from completely shutting down. 

Over time, with wear and tear, you may notice you have a clogged condenser or damaged condenser coils. The system may still work, but it will not work efficiently. If the refrigerant isn't cooled to the correct temperature your system is inefficient and at risk of completely shutting down. You should contact a qualified engineer to sort this. 

The system working harder to generate cool air will result in a rise in energy bills and an increased carbon footprint (and we don’t want that). 


How to recognise any issues with your A/C condenser 

Well, if your energy bills are rising this may be an issue with your air conditioning

If you find yourself refuelling the system a lot more than normal, there may be a problem. 

If you notice that there is a lack of cool air, there is an issue with your A/C system. A lack of cool air can be caused by a system that is leaking (check for pools of fluid around the units). 

If the units are making strange noises - there’s likely to be an issue.

But don’t panic - with a well maintained system these issues are pretty unlikely. 

Maintaining the condenser 

You should always let a qualified air conditioning engineer fix any issues with your A/C system. It is possible to fix some things yourself but if you don’t know what you are doing this can cause further problems. 

Have your air conditioning serviced at least once a year to ensure your system continues to work effectively. 

Change the air filter every 90 days. You should be able to find information on this in the air conditioning manual. 

Make sure that the vents are always clean and free of debris. Pour a mixture of bleach and water down the outside drain. Dust off any dirt from the indoor vent.  

If your house has an air conditioning system over 12kW, you must have a TM44 inspection around every five years. This consists of an energy assessor carrying out an inspection of the units. 

If your air conditioning breaks and you’re in need of help, call BOXT.

At BOXT, you can call us on 0800 193 7777 and our specialists will dispatch an engineer to fix any issues with your BOXT air conditioning system. It may even be something simple - we provide guidance over the phone to help you overcome any problem. Don’t want to call us? Use our live chat service and speak to a specialist. 

If you are looking to purchase a new system, BOXT can help. We’ll provide you with a quote for a new, quality air conditioning system. You can also use our Find an A/C System Tool, which helps you find the perfect air conditioner for your home. 

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