Some common HVAC condenser unit problems

Heating and air conditioning unit in back of a residence

Is your HVAC unit blowing warm air inside? Are you facing issues with your outdoor condenser fan? If your answer is yes, then chances are that the condenser unit of your HVAC is having some problems. An HVAC system has various components but, the components of the outdoor unit are the ones that perform most of the heavy work. Therefore, it is a very important part, and if your outside unit starts malfunctioning, your system will not be able to perform the functions that it is supposed to. Here, we are going to discuss some common HVAC condenser unit problems, so that you can notice them on time and get them fixed.

What is a condenser unit?

The outdoor unit of your HVAC is known as the condenser unit. It includes various vital components of the system such as the compressor, condenser coil, fan, and refrigerant lines. The condenser unit mainly works as the heat exchanger, as it condenses and converts the refrigerant from its gaseous state to a liquid state.

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The functioning of the condenser unit

The compressor increases the temperature to help the refrigerant change its state. Then the condenser coils remove the heat from the refrigerant and release it into the outside air with the help of the fan. The fan performs the function of cooling down the condenser coils and blowing the hot air outside. The refrigerant lines then circulate this cooled-down air, through the HVAC system, into your home. 

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Common HVAC condenser unit problems

Following are some problems that can cause your HVAC unit to malfunction:

  1. Blocked airflow:

    As the condenser unit is located outside the house, it may face blockage issues due to fallen leaves and debris. The condenser unit needs some free space around it so that it can perform efficiently. If there is any kind of blockage then the heat will not be completely released from the unit and get trapped inside it. This accumulated heat causes the system to overheat and some heat can even get released into the indoor air, negating the function of an air conditioner. Therefore, it is advised to keep your condenser unit away from trees, plants, and any other type of obstructions. You can even put a safety net around it, to keep the debris away from the unit.

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  2. Dirty condenser coils:

    When the dirt and debris keep accumulating around the condenser unit, some dirt finds its way inside the unit and to the condenser coils. Dirty condenser coils are inadequate at transferring the outside thus, your house will be hotter than you want it to be. Also, the regular heat being transferred because of the dirty coils will make the system work longer and harder to cool your house down. This will result in higher energy consumption as well as higher energy bills. If you fail to clean the coils as soon as they start malfunctioning, it may also lead to system overheating or breakdown. In that case, the repair cost will be much higher. Contact an expert at the earliest to get your condenser coils cleaned for better performance from your HVAC system.

  3. Bent fins:

    The outside unit of the HVAC system has fins surrounding it. The fins have gaps between them that allow the air to pass through easily. But, in case the fins are clogged or if they get bent due to any reason, then it will restrict the airflow. This restricted airflow will then affect the working efficiency of the entire system. If you notice any bent fins on your outside unit, you can straighten them yourself or call in an expert. 

  4. Fan problems:

    The fan contained in your outside unit is also known as a condenser fan and it helps with the airflow. It is also responsible for removing the heat from the condenser coils and blowing it outside. The condenser fan can develop several issues such as a blown capacitor, electrical issues with wiring, fan motor issues, bent or loose blades, and/or worn fan belt. If any of these issues arise with the condenser fan, it will fail to cool down the coils and release the heat outside. This malfunctioning will lead to hot indoor air, resulting in increased energy usage, higher bills, decreased efficiency, and decreased lifespan of the system. So, if you start hearing any type of unusual sound from your outside unit or if your condenser unit stops working, call in for an expert immediately.

  5. Refrigerant leaks:

    The refrigerant lines present in the outside unit of an HVAC provide a passageway to the refrigerant throughout the system. But, if the refrigerant starts to leak for any reason, the air will not be as cool as you want it to be, and you will also have to do frequent refrigerant recharges causing increased costs. The leak can happen either inside the condenser unit or in the refrigerant lines that connect the condenser and the evaporator coils. No matter where the leak is, it can cause problems such as warm indoor air, compressor issues, or icing issues. Refrigerant leak increases the work pressure on the system and causes increased energy consumption and higher bills. As soon as you see any leakage from your HVAC system, contact an expert and get it fixed to increase your system’s efficiency and lifespan.

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The condenser unit contains all the key components of your HVAC system, making it vital for its working. So, when you notice any of the above-mentioned common HVAC condenser unit problems, contact a professional and get it repaired. If the repair is done on smaller issues from the beginning, it will protect you from higher repair bills and energy bills, also improving the lifespan of your HVAC system.

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  1. 1

    I recently just became an HVAC-R Technician and your article has been helping me out in multiple scenarios so far mapquest. Keep the great content coming.

  2. 2

    Airflow was obstructed. Your condenser unit must be able to breathe in order to function effectively. If you have plants, dino game trees, or other obstructions near your condenser unit, they will restrict the airflow and make it more difficult for your unit to blow the appropriate quantity of air over the coils.

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