Air conditioners use a type of coolant known as refrigerant. There are a few different types of refrigerants used in AC systems, but all of them are chemical compounds that are extremely good at absorbing heat. The refrigerant allows an AC system to capture and remove heat from within a building to lower its temperature. The refrigerant also carries the heat outside and then releases it. This article will explain why having the proper refrigerant level in an AC system is essential and how to know if your AC doesn’t have the right level.
The Role Refrigerant Plays in Air Conditioning
Air conditioning systems operate on a closed loop, meaning the refrigerant continually circulates between the outside condenser unit and the inside evaporator coil. Initially, the refrigerant enters the evaporator coil as a cool liquid. As it flows through the coil, it absorbs heat from the indoor air, causing it to evaporate and change into a warm gas. This warm gas then travels back to the outdoor unit, entering the compressor. The compressor increases the pressure of the refrigerant, which raises its temperature, turning it into a hot, high-pressure gas. This hot gas then moves through the condenser coil. As air flows over the condenser coil, the refrigerant releases its heat and condenses back into a high-pressure liquid. Before returning to the evaporator coil, the refrigerant passes through an expansion valve, where its pressure drops. This pressure reduction lowers the temperature of the refrigerant, turning it back into a cool liquid, ready to absorb heat once again in the evaporator coil.
Why Refrigerant Level Matters for an AC System
As you can see, the refrigerant’s pressure directly impacts its temperature. The refrigerant is extremely hot when under high pressure and quite cold when its pressure is low. Maintaining the proper refrigerant level in an AC system is important to ensure it is under the correct amount of pressure and, thus, at the right temperature during each step of the cooling process.
If the level is too low, the refrigerant will be under lower pressure when it flows to the evaporator coil. This is an issue since low pressure can cause the refrigerant to be so cold that the condensation on this coil quickly starts to freeze.
If the level is too high, the refrigerant will not get nearly as cold as it should. That means it will not be able to absorb as much heat, leading to the AC system cooling less effectively and thus more slowly. If the level and thus pressure are too high, it also makes it more difficult for the compressor to pump the refrigerant throughout the system. This obviously makes the compressor work harder than it should, which can damage its motor or lead to it overheating.
It is rare for an AC system’s refrigerant level to be too high. There are only two situations where it can happen: if the system wasn’t installed correctly or if it was low on refrigerant and someone added too much when recharging it.
Having the refrigerant level in your AC be too low is much more common and almost always indicates a leak in one of the coils or refrigerant lines. It suggests the system has a leak because the refrigerant flows in a closed loop, which means the level should always remain the same.
Signs That Your AC Is Low on Refrigerant
The most common sign that the refrigerant level in an AC system is low is if it starts freezing up almost every time it runs. However, an AC can also freeze due to airflow issues caused by a dirty air filter or malfunctioning blower. If the evaporator coil isn’t cleaned regularly and gets too dirty, it can also lead to the system freezing up. The fact that an AC can freeze for various reasons means you’ll need to have a technician perform an inspection to determine why your system keeps freezing up. During this inspection, the technician will measure the refrigerant charge or level and add refrigerant if necessary. They may also change the filter and clean the evaporator coils and blower if they have become covered in dirt and grime.
Contact the Pros
At Simply Mechanical, we have been serving the residents of Littleton and the surrounding areas since 2018. We install, maintain, and repair heating and cooling systems. We also offer indoor air quality services and can upgrade your thermostat to a smart model. If your air conditioner is not performing as it should, contact us today to schedule an appointment with one of our experienced team members.
