What Does An AC Condenser Do?

Air conditioner systems rely on several components to help cool the warm air in your home or office. One of the most important of these components is the AC condenser.

Q: What Does An AC Condenser Do?

A: The AC condenser is responsible for cooling the refrigerant and condensing it from a vapor into a liquid. It is a necessary step in the air conditioning process. Without it, your AC system will stop functioning.

Understanding How Air Conditioners Work

To fully understand the function of an AC condenser, you need to know how AC systems work. The condenser is one of the following three primary components in a standard air conditioner system:

  • AC compressor
  • AC evaporator
  • AC condenser

From small window air conditioners to large industrial AC systems, all types of AC units typically include these key parts.

Central air conditioners typically include a compressor and condenser housed inside a unit that is placed outside the house. In a small window unit, the condenser is in the back half of the unit, where it is exposed to the outdoors.

The condenser and evaporator are coils that are connected by a series of pipes. The compressor is an electric pump that is used to pressurize the gas.

Most AC systems also include an expansion valve, which is responsible for regulating the transfer of refrigerant into the evaporator coils.

Refrigerant Travels through the AC System

The compressor, condenser, and evaporator form a sealed system containing the refrigerant. These liquids are also commonly called Freon, which was a popular brand name for many decades. Refrigerants are basically liquids that easily absorb heat and can convert from liquid to gas at low temperatures.

These refrigerants do not dissipate, which means that your AC system should never run out of refrigerant. One of the only causes of low refrigerant is a refrigerant leak, which is typically the result of a worn seal or cracked coil.

The refrigerant passes through the three key components, transforming from a gas to a liquid. When the refrigerant reaches the compressor, the refrigerant is a gas. The compressor then compresses the gaseous molecules, which increases the temperature of the gas.

The high-pressure, high-heat gas then passes to the condenser coils, which are typically made from copper. The condenser unit also contains a fan and a set of metal fins. The metal fins and fan help to dissipate heat from the gas that is traveling through the condenser coils, allowing the gas to cool.

As the gas cools it converts back to its liquid state. It is then sent to back to the indoor unit of the AC system where it passes through the evaporator coil. However, it must first pass through a small hole, which increases the pressure of the refrigerant.

Inside the evaporator coil, the refrigerant begins to absorb heat and convert back into a gas. As the refrigerant absorbs heat, the air around the evaporator coils cools. The cool air is then delivered to the house or room by a fan.

The gaseous refrigerant is then sent back to the compressor to repeat this process. This cycle continues until the air inside your house reaches the temperature that you set.

Split System Air Conditioners

Split system air conditioners and window units share many of the same elements. However, there are also several major differences. With a split system air conditioner, the evaporator and condenser are housed in different units.

The evaporator is placed inside the house, typically in the basement or near the furnace, where it can connect to the duct system of your house. The condenser unit is placed outside, where it can get rid of the heat absorbed by the refrigerant.

Window Air Conditioning Units

With a window air conditioner, these elements are packed together in a small unit that is placed in a window. The evaporator coils are near the front, while the condenser coils are near the back. The back of the AC unit should include vents, where the heat escapes from the condenser coil.

Vehicle Air Conditioning Units

Vehicle air conditioning systems are very similar to home AC systems. They still use evaporators and condensers. However, the AC condenser is placed near the engine radiator. It typically includes metal fins that resemble a radiator and performs the same function as AC condensers for home AC systems.

Top Signs of AC Condenser Problems

The AC condenser is essential to the air conditioner process, as it helps cool the refrigerant and convert it back to a liquid. If the condenser coils become dirty, clogged, or damaged, the refrigerant may still convert to a liquid and continue traveling through the AC system. However, without cooling the refrigerant, the AC system becomes less efficient.

One of the top signs of problems with your AC condenser is a lack of cool air. If you notice warm air blowing through the vents, the condenser may be damaged.

When the AC condenser is not functioning properly, the AC system needs to work harder to cool your home or vehicle to the set temperature. With a home AC system, this decreased efficiency often leads to increased energy costs. With the AC system in your vehicle, decreased efficiency can lower the fuel efficiency of your vehicle, eating up more gas.

A lack of cool air may also be the result of a refrigerant leak. These leaks are difficult to detect and repair, especially if the leak is the result of a crack in the evaporator or condenser coil. In fact, many HVAC technicians will not attempt to repair a cracked coil.

The time that it would take to repair the coil and ensure that the repair was successful is not cost-effective. In many cases, it is more affordable to replace the condenser coil or condenser unit than to deal with the challenge of repairing the crack.

How to Protect Your AC Condenser

Air conditioner systems do not require a lot of DIY maintenance. If repairs are needed, they should only be performed by qualified HVAC technicians. However, there are a few steps that you can take to protect your AC condenser.

For your car AC system, the best way to protect the condenser is to have your vehicle serviced regularly. Whenever you take your vehicle to an auto body shop, you should ensure that the mechanic checks all major components, including the AC system.

While window AC units are designed to be exposed to the elements, operating your AC system during a rainstorm may lead to excess moisture accumulating inside the condenser. This increases the risk of corrosion, which may eventually result in a cracked coil and a refrigerant leak. You should avoid using your window air conditioner during severe storms to minimize this risk.

To protect your split unit AC system, you should get it serviced annually. Allow an experienced HVAC technician to examine all the major components and check the refrigerant.

You should also examine the area around the condenser unit. These units are often placed next to the house. Some homes may have bushes, trees, and other plants near the condenser. During the fall, leaves, berries, nuts, and other items may fall and end up inside the condenser unit.

You can keep debris out of your condenser unit by trimming back foliage and plants that grow near the unit. If these plants continue to pose a problem, you can add a cover to the unit during the fall season. However, covers are not needed year-round, as they can trap in moisture.

Last Thoughts on AC Condensers

Air conditioners are not overly complicated appliances. While the designs and configurations can vary, most AC systems include an evaporator, condenser, and compressor. The AC condenser condenses the gaseous refrigerant into a liquid by helping to expel heat.

With a typical split unit AC system used for central cooling, the condenser is placed in a separate unit outside the house. With a window unit, the condenser sits outside the window. Inside your vehicle, the condenser is found near the engine radiator.

When the condenser stops working properly, the AC system may not be as effective at cooling your home or car. You may notice that the air coming from the vents is warmer or not as cool as usual. This may be caused by clogs, cracks, or other damage.

The best way to protect the condenser is to get your AC system serviced regularly. Unfortunately, this is not always an option for window AC units. With a window unit, you typically use the appliance until it stops working. However, you can avoid using it during severe storms.

For a split system AC unit, you should get your system serviced each year. The typical recommendation is to have it inspected early in the year before you plan to start using the AC system regularly.

Your car AC system should be inspected when you take your car in for a checkup. Follow your manufacturer’s recommendations for vehicle servicing, especially if your car is still under warranty.

The main takeaway is that the AC condenser is an important component of any AC system. From car AC systems to industrial AC units, these air conditioners all use a condenser to help get rid of heat.