How do you heat and cool your home? Modern HVAC systems can comprise gas furnaces, heat pumps, air handlers, and other options. What are your choices, and which combinations will work best for your house?
How It Works: Gas Furnace
Most gas furnaces burn propane (LPG) or natural gas.
The Heat Exchanger
Combustible gas fumes can be dangerous, so furnaces separate the hot gas from the home’s air by sending both through metal tubes and chambers inside a heat exchanger. The heat radiating from the gas tubes warms the air in the adjacent chambers without mingling the two streams.
Gas furnaces heat the air in a series of metal tubes called a heat exchanger. When the furnace is activated, it draws air inside a burner unit, then ignites a gas-powered pilot light to heat the heat exchanger. Air flows over the heat exchanger and absorbs heat, and combustion gases are vented via an exhaust pipe.
A network of ducts and vents then distributes the heat generated by the furnace throughout your home. This is called a forced-air system because it uses an air blower to force hot air into the duct network.
How It Works: Heat Pump
An electric heat pump is a furnace and AC alternative that works not by generating heat, as a furnace does, but by moving it from one place to another. The technology heat pumps use to move heat is similar to the tech that a refrigerator uses to move heat.
In heating mode, heat pumps work by extracting heat from the outdoors, either from the air or the ground. The outdoor compressor part of the unit uses that heat to convert a liquid refrigerant into a gas. The gaseous refrigerant is then transferred to the indoor part of the heat pump (called the air handler), and the heat is released inside. As the heat is released, the refrigerant is converted back into a liquid and then transferred back outside to start the cycle again.
One key difference between a heat pump and a furnace or air conditioner is that a heat pump can both heat and cool your home. In contrast, furnaces can only heat your home, and AC units can only cool. A heat pump can do both. It has technology that lets it both transfer heat into the home and remove heat from the home, depending on the mode you select.
In cooling mode, the heat pump essentially does the same thing, but in reverse. The air handler extracts heat from indoors and transfers it to the outdoor compressor for release.
An air handler is a component of heat pump-based HVAC systems. It takes the place of certain components of furnace and AC cooling systems. In a heat pump system, the air handler does the work of distributing the heat that is extracted by the compressor in the outdoor part of the heat pump.
Gas Furnace vs Heat Pump: Comparison
There are four main differences when it comes to a heat pump vs furnace.
Heat generation and efficiency: Heat pumps work by moving heat from one place to another, while furnaces work by generating heat. This gives heat pumps a higher efficiency potential in comparison to furnaces. Heat pumps are generally more energy-efficient and can reduce your energy bill.
The flip side is that because heat pumps extract air from outdoors, they don’t work as efficiently in very cold or very hot climates. Some heat pumps contain a heating coil in the air handler. This coil switches on when the temperature outside is too cold for the heat pump to extract enough warm air. This helps with heating, but the coil is less efficient at heating air. Because of this, running costs increase when the heating coil is active.
Heating and cooling modes: Heat pumps have both a heating and a cooling mode. Depending on your heating and cooling needs and your local climate, you can rely on your heat pump-based HVAC system all year round. In contrast, a furnace can only provide heating. If you have a furnace, you also need some kind of AC for summer use.
Fuel source: Heat pumps run on electricity, exclusively. Furnaces run on gas alone, or a combination of electricity and gas, propane, or oil. Because heat pumps don’t burn fuel, they provide a cleaner source of heating and cooling, in comparison to a furnace.
Indoor air quality: Like AC units, heat pumps also improve indoor air quality by reducing humidity. By reducing the humidity, you may also be reducing the potential for growth of mold, mildew, and funguses in the home.
Which Option Is Best in North Texas?
North Texas has a relatively mild climate in comparison to mid and northern states. This means that heat pumps can provide adequate heating on most winter days. However, there are still occasional freezing days. On those very cold days where the temperature dips below 40 degrees, heat pumps don’t provide as much heating as a furnace.
The main advantage of a heat pump is that it’s more energy-efficient than a furnace, so the long-term operating costs are lower. However, the up-front cost for purchasing and installing a heat pump system tends to be a bit higher than the up-front cost of a furnace.
Another benefit of heat pumps is that in older or smaller homes, there’s not always room for the duct network that a furnace and AC combo needs. In these homes a heat pump or mini split system is the best choice for whole-house heating and cooling.
Choose a heat pump if:
- You can pay the higher up-front cost and want to minimize long-term running costs.
- You’re unable to install a furnace/AC combo due to space restrictions.
- You are in an area where temperatures tend to stay above 40 degrees Fahrenheit.
The main reason to choose a furnace-based heating system is that they’re more consistent at low temperatures in comparison to heat pumps. Furnaces don’t lose efficiency at lower temperatures, so with a furnace you’ll never have to worry about inadequate heating on the coldest days. Furnaces are also cheaper to purchase and install. The exception may be if you are installing a completely new furnace system, with new ductwork, vents, and gas installation. In this case it’ll likely cost more to install a furnace than a heat pump.
Choose a furnace if:
- You prefer a lower up-front cost, paired with higher running costs.
- You have the space for duct installation, or already have a duct network installed.
- You want a more consistent heat source that provides powerful heating even on the coldest days.
- Your home has a larger square footage to heat.
Another option is to go for a system that combines both a furnace and a heat pump. With these combination systems, the heat pump acts as the main heat source. The furnace is a backup that kicks in when the temperature dips below a certain point. This option lets you take advantage of the efficiency and reduced running costs of a heat pump on most days, but ensures you have the heat-generating power of a furnace for the coldest winter days. These are a great choice for homeowners in the Dallas area.
When Do You Need an Air Handler?
If your home relies on a combination of furnace and AC for heating and cooling, you don’t need an air handler. Your furnace already has all the components needed to heat air and move it around your home. And if you pair your furnace with an air conditioning system, the AC has an air handler, so the cooling side of the equation is also covered.
However, if your home uses a heat pump-based system for heating and cooling, then an air handler will be part of that system.
In short: If you have a furnace, you don’t need an air handler. If you have a mini split HVAC system or a heat pump, it’s installed as an integral part of that system.
What Is a Mini Split System?
A mini split is a ductless heat pump, meaning it doesn’t use ductwork to move heat around your home. Instead, the ductless system is made up of several linked but independent heat pumps. Each unit has its own thermostat and controls the temperature for the room in which it’s installed.
A mini split system is a good option if you have an older or smaller home without room for a duct system or if you want to add heat to another part of your house and be able to control the temperature independently.
Need Help Choosing the Right HVAC System? CW Service Pros Offers Expert Advice
It’s always good to get professional help when making important decisions for your home. The HVAC components you choose will serve your home for the next 10 to 15 years, so it’s important to make good choices! For solid professional advice, call the professionals at CW Service Pros. We can help you pick the best system for your needs, and we can also perform installations, repairs, and regular service checks.