May 21, 2015

7 Essential Elements for Air Conditioner Operation

7 Essential Elements for Air Conditioner OperationAir conditioning systems are vital appliances in any central Arizona home. AC systems use the same principles as a home refrigerator. An air conditioner pulls heat out from indoor air and releases the collected heat outside your home. All of the many parts and processes must all work together smoothly to achieve maximum efficiency.

We’re going to break down the 7 main components of an air conditioning system, explain what they do, and show how they are important.

Key Components of an Efficient A/C System

The following are the essential components and how they work:


Thermostats are temperature-sensitive devices that signal the air conditioning system to start and stop. Modern programmable and smart thermostats offer advanced features that help you save energy dollars with automatic temperature changeovers. If you’re still using a mercury-based or digital thermostat, consider moving to a more modern one. While 7 day programmable thermostats are nice, the benefits of using a smart thermostat far outweigh any initial start-up cost.

Fan Motors

Fan motors power the fans that pull and push airflow through the AC unit’s coils, ductwork, and living spaces. The motors, like most moving parts, should be oiled and cleaned during preventive maintenance each spring. This ensures a long life span and efficient cooling.


An air conditioning system has two fans that pull airflow over the evaporator and condenser coils. The fans are in the outdoor unit and help suck in and expel the air. If you have a traditional cube style AC unit, you can see a fan when looking at the top. This only spins when the unit is running and actively cooling.

If you have a more compact unit like a Daikin FIT, you can see the fan on the front. If it is a variable speed system then this should be spinning any time the unit is on, not just when actively cooling.

Evaporator Coil

In a conventional split-system air conditioner, the evaporator coil is located inside the home or nearby the air handler where the blower fan is. Cold refrigerant vaporizes inside the evaporator and draws heat from warm return airflow. Coils should be cleaned each year for maximum cooling efficiency.

As the air conditioner runs, the compressor’s job is to pull cold, low-pressure liquid refrigerant through the tubes in the evaporator coil. Before the refrigerant enters the evaporator coil, it passes through the expansion valve. The valve relieves pressure which quickly cools it.


Most homes that have a central air conditioning system have a split air conditioning system. In these units, the compressor is located in the outdoor unit. This is typically the noisiest component. The compressor’s job is to receive refrigerant from the evaporator coil and prepare the refrigerant to release heat at the condenser coil.

There is a motor that powers the compressor with a piston and cylinder. The compressor compresses the gaseous refrigerant which raises the refrigerant’s temperature so it will change into a high-pressure gas.

Condenser Coil

Where the evaporator coil extracts heat, the condenser coil releases heat at the outside cabinet. The condenser coil is designed similarly to the indoor evaporator coil, but the difference between the AC unit’s evaporator and the condenser coil is opposite.

The evaporator coil gets heat from indoor air, the condenser coil expels heat into the outdoor air.

Air Filter

The air filter’s primary duty is to protect HVAC components from the accumulation of dirt and debris. It also protects your pocketbook from exorbitant energy bills. A dirty evaporator coil loses cooling efficiency and may ice over.

Filters help keep the fan motor clean and prevent early failure. There are many different kinds of HVAC air filters; pleated filters, electrostatic filters, HEPA filters and more.

AC Maintenance

Annual AC maintenance in the spring is vital to keep all these parts in good working order. If you want to save money and make your unit be as energy-efficient as possible, annual maintenance is a must. To learn more about your central air conditioner and its parts, or to schedule a heating and cooling service call, please contact Wolff Mechanical today. We serve residents across central Arizona.

Our goal is to help educate our customers in the Phoenix Valley area of Arizona about energy and home comfort issues.

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