Home Systems 101: Your home's HVAC System
Your home's HVAC system is more than just a collection of mechanical parts; it's the heart of your home's comfort and air quality. Whether it's keeping you cool in the summer or warm in the winter, a well-functioning HVAC system ensures that your living environment is pleasant and healthy year-round. Understanding the different components of this system can help you appreciate how it works and why regular maintenance is essential.
In the following sections, we'll break down the key parts of your HVAC system and explain how each one contributes to your home's overall comfort. From the thermostat on your wall to the ducts hidden behind your walls, you'll learn what each component does and why it matters. Let's dive in and explore the essentials of your home's air handler and condensing unit.
Air Handler
Getting a handle on your air handler
The air handler is the indoor unit for the A/C and Heating system. We can think of it as the central nervous system of your HVAC. Your air handler works alongside your HVAC system's ductwork to deliver air to your indoor spaces through vents and pull air in through the return vents. Curious about a specific part of the air handler? Click an area on the diagram to learn more.
Contactor
The contactor is an electrically controlled switch that allows high-voltage power to flow to the system's components, like the blower motor and compressor.Ignitor
The circuit board is the brain of the system. Its job is to distribute high and low voltage components as needed.Blower
The blower is in charge of dispersing air throughout the house.Auxiliary Heat
Also known as “emergency heat” or “electric heat,” this component is heated by high voltage electricity passing through the metal coils, causing them to get very hot, warming the air pushed by the blower into the home.Metering Device
This device can be a TXV, EEV, or a piston. Regardless of the type, its job is to regulate the flow of refrigerant into the coils.Evaporator Coils
An evap coil absorbs heat from the indoor air, causing the refrigerant inside the coil to change state from a gas to a liquid. That cools the air as it passes through the coil. With a heat pump in heating mode, the evaporator coil and condensing coils’ jobs are reversed.Drain Line
Usually made of PVC pipe, the drain line takes the condensation built up from the evap coil and redirects it to a drain in the floor, into a condensate pump, or outside the home.Float Switch
This safety device protects the home from flooding if the drain line clogs. It will shut off the HVAC system until the water backup is cleared.Condensing Unit
Your condensing unit, condensed
The condenser is the outdoor unit of the A/C system. Depending on the time of year, the condenser works to release or collect heat. Click an area on the diagram to learn more about the specific components that make up your HVAC system’s condenser unit.
Contactor
The contactor is an electrically controlled switch that allows high-voltage power to flow to the system’s components, like the blower motor and compressor–when activated by a control voltage signal from the thermostat or circuit board.Capacitor
This component stores the extra energy needed to start the compressor and condenser fan motor.Condenser Fan Motor
The condenser fan motor is responsible for pulling air through the condenser coil, thereby cooling the refrigerant within.Compressor
The compressor is the heart of the system. This motor is solely responsible for pushing refrigerant throughout the system. When the compressor pushes the refrigerant, it is also compressing the incoming low pressure gas into the discharge as a high pressure gas into the condenser coil.Condensing Coil
The condensing coil receives refrigerant from the compressor, as the fan motor pulls air through the coil to change the temperature of the refrigerant.Service Valves
These are the entry and exit point of the refrigerant lines into and out of the condensing unit. This is where a technician can use their gauges to test the refrigerant levels of the system.
Was this article helpful?
