West Haven, Connecticut
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West Haven, CT 06516
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5 Key Components of an Air Conditioner July 3, 2019

West Haven, New Haven County
5 Key Components of an Air Conditioner, West Haven, Connecticut

Air conditioners depend on several vital components to produce the cool air that keeps you comfortable throughout summer. When it runs efficiently, you don’t need to think about it much. But if the unit suddenly stops working, it could be difficult to explain the issue to an HVAC contractor. Understanding how the key parts of the system function will help you determine what the problem is and explain it to a technician. 

The Key Parts of an AC System

1. Refrigerant

In order for your air conditioner to cool the house, your HVAC contractor must supply it with refrigerant, or coolant. This substance is carried through a closed loop system that transports indoor heat to the outdoor unit. As it absorbs that heat, it transforms from gas to liquid. The refrigerant then continues its journey to the exterior unit, where the heat is extracted.

2. Compressor

HVAC contractorThe compressor plays a vital role in applying pressure to the refrigerant in order to raise its temperature. This is necessary for the system to expel the heated air outside, which occurs when it comes into contact with colder air. The pressure is exerted with such force that the refrigerant temperature becomes higher than the temperature outside.

3. Condenser Coil

Situated in the exterior unit, the condenser coil is the receiving point for the pressurized refrigerant as it arrives from the compressor. The coil transfers heated air to the outdoors. For the process to work, the condenser fan must emit air over the coil. The heat is expelled, and the refrigerant begins its journey back inside.

4. Expansion Valve

Although the refrigerant expels heat as it leaves the condenser coil, it remains very hot as it makes its way to the evaporator coil. The expansion valve is designed to cool it down by decreasing pressure, which lowers its temperature.

5. Evaporator Coil

The expansion valve sends this low-pressure substance to the evaporator coil. As the air inside your home blows over this now cold coil, its heat is naturally absorbed. At that point, the refrigerant evaporates and returns to its original vapor form.


When you need AC repairs, contact the HVAC contractors at Apple Oil. They are committed to your comfort and satisfaction. They’ve served homeowners and business owners throughout Fairfield and New Haven counties, CT, for more than 50 years. They’re proud to offer a wide range of services, including air conditioning maintenance, oil furnace repairs, and same-day heating oil delivery if you call by noon. New customers also receive a discount on their first delivery. Visit them online to learn more about their services, or call (203) 934-3835 to speak to an HVAC contractor.