Furnace vs. Air Handler

What is the difference between a Furnace and an Air Handler?

Have you ever wondered if you have a furnace or air handler? In all the jargon and technical details surrounding the installation of HVAC systems in your home, it’s easy to get mixed up on which devices do what. This applies particularly when it comes to the difference between equipment that heats and cools your home.

You would be surprised at how much confusion there is in the distinction between furnaces and air handlers. Both are used in HVAC systems, and they look very similar while delivering certain comparable functions. However, each has their own particular mechanics, which can easily cause confusion between the two.

Let’s start out with some basic definitions of these units first.

Furnace: Structure in which heat is produced with the help of combustion. The various types of furnaces differ in how they work— single-stage, two-stage, variable speed, and the fuels that power them— gas, oil, and electric. While the basic operation remains the same, these have specific characteristics, costs, and efficiency ratings.

Air Handler: They move air through a refrigeration coil and into the ductwork. They also have electric heating elements similar to a clothes dryer for emergency heat or auxiliary heat to assist a heat pump. Typically partnered with heating and cooling components, such as heat pumps or in some cases, a hot water coil from a boiler.

Let’s get into what a furnace is and does:

If you take a close look at the heating system in your home and you notice that it has more than four different parts, then you’re probably dealing with a furnace.

If you have a gas fired furnace, you are either on propane, heating oil or natural gas, depending on what your area offers and if you prefer one over the other. Gas fired furnaces can produce large amounts of heat and will heat larger areas quickly and efficiently. With furnaces, you can have a single stage, two stage, or modulating gas operation. When you have a furnace that requires duct work, you can couple that with a refrigeration coil and a heat pump, and you got yourself a split system (not to be confused with a mini-split, we will cover that in another post). All gas furnaces have main components that consist of an internal combustion chamber in which the fuel itself is burned and turned into heat energy. It also has a channeling system that pushes heat into your home’s ventilation system while another part of the furnace works at filtering out byproducts.

Unlike gas furnaces that lose some of that heat, there are also electric furnace that don’t burn anything at all. Instead, they produce heat through electric resistance and then transfer it throughout your home. Electric furnaces work kind of like a hair dryer. They pull air into the system and across the heating elements. The electric heating elements warm the air and then the blower delivers the heated air throughout your home or business. Electric furnaces are typically less expensive and do not a require the exhaust ventilation system like a gas furnace, but the cost is a little more to operate, so you might find that having a propane or natural gas fueled home will save you some money on your electric bill.

Let’s get into what an air handler is and does:

Air handler can also be referred to as a Fan coil unit and it is basically a box, shaped like a furnace. They typically have a refrigeration coil and blower inside. In most cases, an air handler is paired with a heat pump or another source for heating and cooling. Within the air handler there could be electric resistant heat as stated earlier. This will then push conditioned air through your ductwork and into your home or business.

Unlike a furnace, air handlers by themselves don’t actually burn fuel to produce heat, they instead work on the dynamics of electric, refrigeration and coil heating to cool or warm up air as it’s forced in and out of your home or business. The air they move is heated through an electric heat pump that’s attached to the air handler itself or it may be air that has been cooled by an air conditioner.

In essence, an air handler is a forced air blowing system that includes a fan called a blower, which circulates air around pipes in your home and business. This blower “handles” your cooled or heated air (this is where the name air handler comes from). This

can make them extremely inefficient in exceptionally cold climates, while also making them highly useful in warmer climates.

How Air handlers and furnaces are similar:

In both furnaces and air handlers, there will be a blower fan that pushes air throughout the ductwork in your home. With furnaces, the air is only heated and not cooled before warming your home, while with an air handler, air can be moderately heated or cooled as needed.

Another thing they have in common is that they are both controlled by a thermostat that regulates the heating and cooling in your home and business when they are turned on or off. However, in the case of an air handler, the thermostat can control your AC, which a fuel burning furnace doesn’t offer.

To sum up what we now know about these units:

The most crucial difference between a furnace and an air handler is a furnace actually produces its own heat while an air handler doesn’t create heat at all.

Air handlers and furnaces aren’t often found together, if at all. Air handlers tend to be used with a heat pump and helps manage air flow throughout your home or business. Some units also provide backup heating elements to help out the heat pump.

Most air handlers connect to both a heat pump and an AC coil in order to heat and cool your home as needed.

A furnace works on a different concept. Utilizing a fossil fuel and a combustion chamber, heat is transferred to the air stream by air passing over the heat exchanger as it warms from the combustion of said fuel. These systems require regular maintenance to keep up on the components that provide its ability to light the fuel each and every time the system is called upon.

Safety of gas fired furnaces is a priority. Regular inspections of your furnace will ensure the integrity of all components and keep you and your family safe.

It’s the heat channeling system that we mentioned above which causes the main confusion between furnaces and air handlers. Both of these devices can heat your home or business, but while a furnace also produces heat an air handler can heat and cool.

Which one is right for you?

Generally speaking, if you live in a location with extreme winters and mild summers, a furnace is a much better option that’s also cost and energy efficient.

If, on the other hand, you have mild winters and hot summers, an air handler, in combination with a heat pump, might be better suited for you.

Whether you go for or have an existing furnace or air handler, Cozy Heating can help you maintain and keep your units running, giving you the perfect comfort for your home or business in any season.