How to Tell What Kind of HVAC System You Have
What Type of AC and Heating System Do I Have?
Outdoor unit on a split HVAC system
If you’ve just moved into a new house, you may not know what type of HVAC system you have. Maybe it’s been too many years since you paid attention to your existing system. When you check your thermostat or walk outside to inspect your unit, you may find it a little too complicated and give up.
Either way, homeowners should be aware of the type of heating and cooling system they have, how it works, and if it’s efficient enough for their needs. That way, they’ll have a stronger idea of their options for affordable maintenance and potential upgrades in the future.
In this post, we’ll explore the four main types of the HVAC systems and units most commonly found, all the benefits they have for homeowners, and which system types are right for your home.
Split System
What is a split system?
A split HVAC system is when you have an outdoor unit connected to an indoor unit by copper refrigeration lines.
The most popular type of home heating and cooling system installed is the split system. When you think about air conditioning units, your first mental image will probably be of the split system.
Your outdoor HVAC unit is a traditional condensing unit that works with indoor components like your evaporator coil, blower, and/or furnace. The condenser for these cooling systems is the most archetypal version of an air conditioner unit in the United States.
It’s very common for homeowners to assume split means, one unit upstairs and one unit down. This is not the case.
How to tell if it’s a split system?
Look at the above image. First of all, notice the shape and size. All major brands have split outdoor units that are similar in shape and size. Now notice that the only things connecting the unit to your home are the whip (electrical power cable connected to the disconnect) and the insulated copper lines penetrating the wall into your home.
The indoor unit will be in a utility room, basement, closet, or attic. It will sometimes be in a crawlspace. The easiest way to find it is to follow your return duct. If it’s ductless, then you’ll most likely have a wall-mounted unit. But it could also be floor mounted.
Possible combinations or configurations for a split system
Heat pump with air handler: Combines an outdoor heat pump unit with an air handler. The air handler will contain the blower, indoor coil, and electric heater kit. The heat pump heats your home until outdoor temperatures reach about 40 degrees. Then electric heat comes on to supplement the heat pump, also called emergency heat. The emergency heat will also come on when your thermostat setting is 3 degrees higher than your home temperature or to defrost your outdoor unit.
Straight cool air conditioner with gas furnace: Combines an outdoor straight cool condensing unit with an indoor cased evaporator coil and gas furnace (pictured in the below image). The blower and furnace heat exchanger are contained within the furnace cabinet and are in a separate case from the evaporator coil. In the below image, the evaporator coil is sitting on top of the furnace. But it could also be beside it in a horizontal application or under it in a downflow application.
Heat pump with gas furnace (also known as hybrid or dual fuel): Described below.
Manufactured homes: Nearly all manufactured homes (unless customized or modified aftermarket) will be a split system. The indoor unit will typically be an electric downflow furnace. Your outdoor unit should be a heat pump if possible. Electric resistance heat will cause high utility bills.
Packaged System
Packaged HVAC systems have the entire refrigeration system contained within one single enclosure and are connected to the home or business by ductwork.
Many homeowners have packaged heating and cooling systems. These heating and cooling systems include both furnaces and air conditioners and are a somewhat common form of home central air conditioning systems. If you have a packaged system, you’ll likely have a large outdoor unit covered by a metal hood. This hood protects against debris, rain, and small animals and insects.
These all-in-one heating and cooling systems vary in appearance but tend to be larger metal boxes with plenty of ductwork and wiring leading to and from the unit and your home. They function in much the same way as other HVAC units and at similar efficiency when providing cool air through traditional ducts.
You’ll sometimes find units in these in commercial settings as well – especially if your building lacks adequate space for the usually larger components of split systems.
Hybrid Split System
Hybrid split systems combine an indoor gas furnace with an outdoor heat pump condenser.
Hybrid air conditioning systems, also known as dual fuel, are very similar to normal split systems except for one key difference: they can switch between heating power sources. Hybrid air conditioner systems give you a choice between natural gas and electric heat.
Hybrid split systems are set to shift heating sources at lower outdoor air temperatures. Conventional heat pumps do not heat well when outdoor temperatures are 40 degrees or less. When outdoor temperatures are this low, your dual fuel system will shut off the outdoor heat pump and use the gas furnace for heat. This is different than a typical heat pump split system where the heat pump continues to run and electric heaters supplement it.
It’s important to note that inverter-driven heat pumps like the ductless unit work down to as low as -10 degrees.
How do I tell if my furnace is 80% or +90% AFUE?
This is an important question because the price difference is significant and because the installation materials needed are much different. The main physical difference in the flue vent piping. In the image above, notice the flue vent piping coming out of the top is sheet metal. This is a sure indicator that it’s an 80% AFUE gas furnace.
AFUE for a high efficiency furnace can vary between 90 and 97%. So, in the industry it is typically generalized by calling it a 90% furnace when it may actually be 92 or 97%. A 90% furnace will have PVC for the flue vent instead of sheet metal. It will also have a second penetration in the top for fresh air return. Depending on the location of the furnace it may be connected by PVC to an outdoor vent or could be a short piece of PVC sticking up a few inches off the top. A 90% furnace will also have a PVC drain for the furnace. The condensation is created secondary heat exchanger and must be drained.
Ductless Mini Split Systems
Ductless mini-split heat pump used in a commercial application.
This is another option typically installed for homeowners in more temperate climates. Ductless split systems operate with several smaller air conditioning units connected through an outdoor compressor. The treated air they provide can be changed from room to room as the units tend to be installed directly into the zones that need heat and cooling.
Ductless systems are also excellent for properties where a lack of traditional ducts makes installing ductwork too difficult or altogether impossible.
The downside of a mini-split system is the maintenance factor. Because there are so many smaller sections of the system, you may need more frequent maintenance to ensure every part works at optimal efficiency. It can also be difficult to source repair parts.
What About a Heat Pump?
When you hear the term heat pump, you might expect it’ll only be used during the winter months. The term heat pump heater is something of a misnomer – heat pumps are very similar to traditional air conditioners.
The only difference is that when you need to reverse its function, it supplies heat. If your house is in a part of the world where temperatures rarely dip below freezing, a heat pump may be just right for you.
Similar to the way heat pump in your refrigerator works, a heat pump uses electricity to move heated air from areas with cool air to areas with warm air. Heat pumps typically operate like mini-split systems with both an indoor cabinet and an outdoor cabinet.
Determining Make and Model
If you need to find out more specific information regarding your HVAC system, you don’t need to have a thorough understanding of all the components. Instead, you can simply look for the logo or label. Once you find it, you should know your HVAC system’s brand and model number.
Afterward, you can Google and find out more detailed information like the efficiency ratings of your air conditioning system and what categories it falls under. This can be especially helpful for homeowners who aren’t sure whether they have a heat pump, electric hybrid heating system, electric hybrid heating system, split system, or one of many other HVAC systems.
What Type of HVAC System is Right for You?
Now that you know the types of common HVAC systems, you may wonder if your current system is ideal for your house. Some heating systems are outdated, and older furnace and air conditioner models may not be as efficient as newer ones. HVAC units are pieces of technology that should be kept up-to-date – in other words, it’s not just about keeping a fresh air filter year-round.
Consider Climate Zones
Think about this: if you live in Las Vegas, you probably have a very different climate than you would living in Miami. The heating systems most common in Minnesota (where they hardly need an air conditioner!) will be dramatically different from those systems found in New Mexico. Mild climates and moderate climates may also require different heating and air conditioning systems for their indoor air needs.
Consider where you live and the type of furnace and HVAC systems you see regularly. Additionally, consider what your desired temperature might be throughout the year for your indoor environment.
Conclusion
Trust the Experts
Each HVAC unit and system type we’ve described has its own benefits, for heat and cool air. They also have their downsides, depending on your specific needs for heat, utility bills, moving air in your building, and so on.
That’s why your next best step is to reach out to a professional HVAC company. Find out what heating and air system types are most common in your area. If you have specific, heating system needs, your HVAC contractor can let you know which furnace systems will suit your needs the best.
If you want to know the type of system they recommend most, they’ll provide you with a range of affordable choices that suit your family, your budget, and your home.
Frequently Asked Questions
What type of HVAC system do I have at home?
Identify your system by checking your thermostat or examining the outdoor unit. Common types include split systems, packaged units, and ductless mini-splits.
How often should I replace my HVAC filter?
Filter replacement frequency depends on factors like filter type and household conditions. As a general rule, check and replace disposable filters every 1-3 months.
What's the optimal temperature setting for my HVAC system?
A comfortable temperature setting typically falls between 72-78°F. Adjust based on personal preference and energy efficiency goals.
How can I improve energy efficiency with my HVAC system?
Regular maintenance, proper insulation, and investing in a programmable thermostat are effective ways to enhance energy efficiency.
What are the signs that my HVAC system needs professional maintenance?
Look out for irregular heating or cooling, strange noises, increased energy bills, or frequent cycling. These may indicate the need for professional inspection and maintenance.
