HVAC Diagram
Our HVAC Diagram helps you understand the different components of your residential heating and cooling system. Learn from the experts at Standard Heating.

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Air Conditioner Equipment
The outdoor condenser unit is not the only part of your A/C. The air conditioning system includes the following components:
Evaporator Coil: In a system with a furnace, the evaporator coils sits on top of the furnace and is the critical component that cools air inside a home. The furnace blower passes air across the evaporator coil. During this process, the air cools as it comes in contact with the cold coil and heat transfers from the air to the refrigerant.
Condenser Coil: This part of the air conditioning system cools (removes heat) from refrigerant and is located in the outdoor condenser unit.
Compressor: A machine used to supply air or other gas at increased pressure, located in the outdoor condenser unit.
Fan: A mechanical device that creates a current of air.
Refrigerant Filled Tubing: Circulates refrigerant between outdoor condenser unit and indoor evaporator coil.
Gas Forced Air Furnace Equipment
Return Air Duct (from rooms): A duct carrying air from a conditioned space to the mixing air duct or plenum unit.
Filter: A porous device for removing impurities or solid particles from the air that passes through it.
Blower: a mechanical device that creates a current of air. See fan also.
Air Handling Unit (AHU): a device used to condition and circulate air as part of a heating, ventilating, and air-conditioning (HVAC) system. An air handler is usually a large metal box containing a blower, heating or cooling elements, filter racks or chambers, sound attenuators, and dampers. Air handlers usually connect to a ductwork ventilation system that distributes the conditioned air through the building and returns it to the AHU.
Air Supply Duct (to rooms): A duct that carries conditioned air from air supply units to room diffusers or grilles.
For a full HVAC glossary see the Whole Building Design Guide.