Warner Service has covered the basics of an HVAC system. However, with summers arrival, many people ask about the anatomy of their window and central A/C units. Here’s our breakdown:

Window A/C Units:


Photo courtesy of Green Living Ideas

Adjustable louvers: This function helps direct the airflow in the direction of your choice. Most controls have at least up-and-down control of the air. Some units may have left and right louver controls as well.

Blower: This device transfers warm air away from a desired location and returns cold air.

Evaporator coil: Located inside or near the air handler where the blower fan is, they’re made from copper, steel or aluminum to help the coolant become gaseous, absorbing heat from surrounding air

Compressor: This is the part that pressurizes gas.

Condenser coil: This is the area where heated gas becomes a liquid, releasing its heat to the outside air.

Control panel: This feature helps you control the air conditioning functions, from the fan speed and timers to auto random reset and so on.

Fan: The fan inside the window A/C unit's assembly is located between the condenser and the evaporator coil. Its double shaft fits the blower on one side, and the condenser fan on the other side.

Filter: Air filters prevent dust and grime from building up on air conditioner’s coils and improve indoor air quality by keeping dust out of your home.

Front grill(e): The front grill(e) provides a direction to the air that’s being distributed into your home. It also protects you from the mesh filter screen and mechanics of the window air conditioning unit.

Partition: This part separates the fan from the blower, so air can freely flow through the window A/C unit.

Thermostat sensor: This part detects temperatures and sends a resistance signal to the A/C control panel, so automatic adjustments can be made to keep your home at the correct temperature.

Central Air Conditioner

It’s important to realize that window A/C units are smaller versions of central air conditioners, which means the latter still contains a compressor, evaporator and condenser coils, fan, thermostat sensor, air filter, and blower. You can see those parts in the diagram below:


Photo courtesy of Altitude Comfort

Air duct: In a home’s distributed heating and cooling system, air flows through a system of air ducts that evenly distribute heat and air conditioning throughout your home.

Condensation drain tube: This part removes condensation produced by the air conditioner's evaporator coil. It prevents the growth of algae and mold, elevated humidity, musty odors, and water damage inside your home.

Floor drain: This is a plumbing fixture that’s installed in the floor of your home. It’s designed to remove any standing water near it, preventing water damage from a broken condensation drain tube.

Furnace blower switch: A furnace’s blower circulates air throughout your home, and the switch controls whether it’s on or off.

Copper tubes: These tubes keep the flowing air warm. Copper is used instead of aluminium because of its resistance to corrosion, high level of heat transfer, machinability, and consumption of less refrigerant. They’re also easier to repair.

Plenum: This is an enclosed chamber where a treated substance collects for distribution, as heated or conditioned air through a ventilation system.

Room thermostat: You can purchase a traditional, programmable, or smart thermostat for your home. Get more information on each in A Quick Guide To Programmable Thermostats And More.

Shut off switch: This safety switch is simply designed to turn your unit on and off.

We hope that we’ve covered enough basics for you to diagnose small air conditioning problems in your home. If you’d rather call for a professional diagnosis, feel free to contact Warner Service or schedule an air conditioning service appointment today:

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