At Greentech Engineering Heating and Air, we believe the more you know about your home’s HVAC system, the better you can care for it—and get the most comfort and efficiency from it. Let’s take a walk through the main components of a residential central split HVAC system, how they work together, and how setups may vary depending on your home.
🧊 What Is a “Split” HVAC System?
A split system means your heating and cooling equipment is divided into two parts:
– Outdoor unit: where heat exchange takes place (condenser or heat pump)
– Indoor unit: where air is heated or cooled and pushed through your home
🔧 Key Components of a Central Split HVAC System
1. Outdoor Unit (Straight Cool Condenser or Heat Pump)
– Contains the compressor, condenser coil, and fan
– Connected with indoor coil by two copper refrigerant lines
– Releases heat to the outside during cooling (or gathers it in heating mode if it’s a heat pump)
*In most cases, a straight cool condenser and a heat pump unit looks identical. It’s hard to tell which type of unit you have in your home. Searching your unit’s model number will be the most effective way to determine your system type. Or by checking your thermostat, if you have an “Emergency Heat” function on your thermostat, more than likely your unit is a heat pump. Otherwise, it’s a straight cool condenser.
📸 Outdoor condenser unit (for cooling or heat pump systems)
2. Indoor Coil (Evaporator Coil)
– Sits inside the air handler
– Connect to the gas furnace *right next to the furnace with horizontal application or sits on top of the furnace with up-flow application
– Cools your home by absorbing heat from air that flows over it
– Also helps dehumidify the air in summer
📸 Evaporator coil inside indoor unit
3. Furnace or Air Handler
– Gas Furnace: Burns natural gas to create warm air in winter. Has a blower to move air year-round.
– Air Handler: Fully electric version of a furnace that uses an electric heat kit to provide heat in winter. Also has a blower to move air year-round. You can think an air handler is a compact version of gas furnace + coil.
📸 Gas furnace or air handler cabinet
4. Supply and Return Plenums + Ductwork
– Return Ductwork: Pulls in air from your rooms and sends it back to the HVAC system to be heated or cooled
– Supply Ductwork: Delivers the conditioned air from the system into your home
– Plenums are the large metal boxes attached to your indoor unit where ductwork connects
📸 Supply and return duct connections to furnace/air handler
👉 Why it matters:
Leaks, clogs, or insulation problems in ductwork can cause uneven heating/cooling and raise your energy bills. We inspect all this during maintenance!
5. Thermostat
Your wall-mounted control panel that tells your HVAC system what temperature you want, and when to switch modes.
🔁 Common Residential HVAC System Setups
- Straight-Cool + Gas Furnace
– Cooling: Outdoor condenser & indoor evaporator coil
– Heating: Gas burners
– Ideal where natural gas is available2. Straight-Cool + Air Handler
– Cooling: Outdoor condenser & indoor coil in air handler
– Heating: Electric heat kit
– All-electric setup3. Heat Pump System
– Cooling & Heating: Outdoor heat pump + indoor coil
– Backup Heat: Electric heat kit
– Energy-efficient in mild climates
🧼 System Health = Home Comfort
Maintaining your HVAC system includes:
– Changing filters every 1–3 months
– Keeping outdoor units clear of debris
– Scheduling an annual system tune-up
– Having ducts inspected for leaks or dust buildup
🏡 We’re Here to Help
Understanding your HVAC system helps you make informed decisions, reduce energy costs, and stay comfortable year-round. At Greentech Engineering Heating and Air, we’re committed to honest service, smart solutions, and customer education.
📞 Have a question or need a system check-up? Call Greentech today!
469-511-6806
