Pretty much all homeowners are familiar with what a home heating or cooling system is. However, when it comes to understanding the core elements that make up each type of system, not all homeowners are familiar with what these are. To help you have a better understanding of your HVAC systems, we’re going to go over some of the main components of both heating and cooling systems below.
Thermostat
Probably the component that many homeowners are most familiar with is your HVAC system’s thermostat. This device is considered the brains of your entire system as it controls when your heating or cooling system turns on or off. With most types of HVAC systems, you’re only going to have one main centrally located thermostat. This thermostat will control the temperature settings for your entire home. If you opt for a zoned HVAC system or a ductless mini-split HVAC system, then you’re going to have multiple thermostats to control the temperature in different areas of your home.
Air Handler Unit
An air handler unit is the indoor part of your HVAC system that works to circulate treated air throughout your home. If you have a furnace, it will have its own built-in air handler unit that can be used for both your furnace and your central air conditioning system. However, if you rely on a heat pump, then you will need to get a dedicated air handler inside your home.
The air handler unit has multiple components inside of it that work to distribute air. These include things like the blower fan, blower motor, fan belt, air filter, and an evaporator coil. As the blower motor turns on, it will force air from your furnace or heat pump to the various supply vents throughout your home. It will also pull air in all your return vents and through its air filter on its way back to your furnace or heat pump.
Ductwork
Most HVAC systems rely on ductwork to deliver treated air throughout the various rooms of your home. Ductwork is comprised of various ducts, branches, plenums, and other features. Ducting will run behind your walls and floors, where they’re out of plain sight. Each duct will connect to a supply or return vent in each room of your home. All the hot or cold air that your HVAC system produces will be circulated through your ductwork via your indoor air handler unit.
Evaporator Coil
Inside your indoor air handler unit is going to be an evaporator coil. Running inside the coil is a substance called refrigerant that’s responsible for absorbing heat from inside your home during the summertime. Your indoor air handler unit will pull hot air from the rooms into your ductwork and pass it over the evaporator coil.
Because heat naturally wants to move to a low-pressure substance, it will move out of the high-pressure air and into the refrigerant inside the coil. During this process, excess humidity will be removed from the air as water droplets form on the surface of the evaporator coil. The water droplets will fall off and go down into a drain and the now hot refrigerant will be pumped to your outdoor condenser unit to get rid of its heat.
Condenser Unit
All air conditioning and heat pump systems will have an outdoor condenser unit. This is the large unit that sits on the outside of your home and is responsible for dispersing heat from inside your home to the outdoors in the summertime. The condenser unit has multiple internal components, including a condenser coil, blower fan, blower motor, fan belt, and more.
Condenser Coil
Just like the evaporator coil, the condenser coil is also filled with refrigerant. Your air conditioning system will have a direct copper line that runs from the indoor air handler unit to the outdoor condenser unit, where your condenser coil is housed. As outdoor air is forced over the condenser coil, heat will naturally move from the high-pressure refrigerant to the low-pressure air. This allows heat to be dispersed into the air outside and the remaining refrigerant to go back inside and do the cooling process all over again.
Heat Exchanger
All furnaces that rely on burning fuel to create heat will have a heat exchanger. This heat exchanger sits inside the furnace and will absorb heat from the combustion process and distribute it through your ducting. It also works to prevent toxic exhaust fumes from the combustion process from entering your home.
Compressor
Inside the outdoor condenser unit for both air conditioning systems and heat pumps is a component known as a compressor. This compressor is essentially responsible for compressing refrigerant gases so that it can enable either heating or cooling your indoor environment. For example, your compressor will receive low-temperature refrigerant from your evaporator coil when it’s cooling. It will work to increase the temperature and pressure of the refrigerant by compressing it. This helps to ensure that once the refrigerant reaches the condenser coil, it can successfully release its heat.
Air Filter
All HVAC systems will have an air filter that sits in the return ducting. This filter is responsible for trapping unwanted airborne particles before they enter the internal components of the HVAC system. As a homeowner, it’s a necessity to ensure that you’re regularly replacing the air filter as an overly dirty filter can restrict the airflow in your system and ultimately lead to overheating of your HVAC system.
Reversing Valve
All heat pumps will have a reversing valve that’s responsible for changing the direction of refrigerant flow. During the summer months, refrigerant will flow from the evaporator coil out to the condenser coil in your outdoor AC unit. However, in the wintertime, refrigerant needs to flow from the outdoor condenser unit to the indoor air handler unit. This is where the reversing valve comes into play as it can switch the flow of refrigerant to go from outside to inside.
Combustion Chamber
All furnaces that physically burn fuel, like heating oil, propane, and natural gas, have an internal combustion chamber. Inside this chamber, there is an igniter, fuel supply line, and burner. Whenever your thermostat tells your furnace it’s time to turn on, its igniter will send a spark to the burner. As fuel flows through the burner, it will be burnt via the burner’s flame. This creates heat energy that flows through the heat exchanger and eventually through your ductwork into the various rooms of your home.
Mini-Split Units
Mini-split units are generally used with a ductless heat pump setup. These essentially work like indoor air handler units except each mini-split unit has its own built-in thermostat. Its internal thermostat will tell it when to turn on and off based on the specific temperature of the room that the mini split unit is in. This type of system doesn’t rely on ductwork.
Trustworthy HVAC Service
CAM Air offers trustworthy HVAC service for Mesa, AZ. Our technicians can help with all your heating, cooling, refrigeration, indoor air quality, heat pump, ductless mini-split, water heater, and commercial needs. Contact us today to schedule a consultation.
