Heat pumps are gaining popularity here in the Pacific Northwest. They offer extraordinary energy efficiency and excellent performance, even through our region’s cold winters. Since they operate on different principles than traditional heating and cooling systems, however, plenty of homeowners don’t quite understand how they work. One question that the team here at Apollo Plumbing, Heating & Air Conditioning hears all the time has to do with why heat pumps rely on Freon.
The question makes sense, given that most people’s experience with Freon comes from old air conditioners and refrigerators. Since they associate Freon with cooling systems, they wonder why heat pumps use it. To answer that question, we’ve put together this guide to how heat pumps work and how Freon’s involved in the process.
A Family of Refrigerants
Before we delve into how and why heat pumps use Freon, there’s something we should clarify. It’s that the term Freon doesn’t refer to a single substance. It’s the trade name for a specific refrigerant first created by the DuPont corporation. Like Band-Aids, the product proved so popular that people now call every similar refrigerant Freon.
That’s somewhat ironic since Freon — known as R-22 — is now illegal to manufacture almost everywhere in the world. It’s a member of a class of refrigerants that scientists discovered were damaging the Earth’s ozone layer and contributing to climate change. There are very few remaining air conditioners or refrigerators that still use it, and Freon itself is getting harder and harder to find.
In Freon’s place, most newer AC and refrigeration systems use a variety of more environmentally-friendly refrigerants. Each new generation is less harmful to the environment than the last. Nevertheless, people still refer to these new refrigerants by the name Freon. For simplicity’s sake, we will too.
How Heat Pumps Work
Now that you know what Freon is — and what it isn’t — we can explain how heat pumps use it. Let’s begin with how heat pumps operate. A heat pump is similar to an air conditioning system in that it collects heat from inside your home and vents it to the outside environment. In doing so, it replaces the hot air in your home with cool, more comfortable air. It only operates that way in the summer, however.
In the winter, heat pumps, unlike air conditioners, can operate in reverse. They absorb heat from the outdoor air and use it to raise the temperature of the air inside your home. Unlike traditional heating systems, heat pumps typically don’t use energy to create heat, except when outdoor temperatures are low enough to warrant some auxiliary heating capacity.
Freon is the key to both processes. In the summer, it’s what absorbs the heat from inside your home and carries it outside to dissipate in the outdoor air. In the winter, it absorbs the heat from the outdoor air and brings it indoors to heat your home. It’s all possible because Freon isn’t only a refrigerant. That’s something of a misnomer. It’s a heat transfer fluid.
How Freon Moves Heat
To understand how Freon works to move heat around, you need to understand a bit about its chemical properties. Freon, and all other types of heat transfer fluids, take advantage of how their temperature changes as they move from a liquid to a gaseous state and back. We’ll begin with how it works in the summer.
When Freon exists as a gas, it remains very cold. Since heat naturally moves toward cold and vice-versa, that allows it to absorb heat as it passes through a set of indoor coils. As it does, a blower fan passes warm indoor air over the coils. The Freon absorbs the heat and cools the air as it does so. Then, the Freon moves outside to the heat pump’s outdoor unit.
There, a compressor raises the gas’s pressure, making it even hotter in the process. The superhot compressed gas then passes through the outdoor coils as a fan blows outside air through them. Since the compressed gas is far hotter than the outdoor air, the Freon releases its heat into the environment, turning back into a liquid state as it does. The process doesn’t end there, though.
The Freon then passes through a device called an expansion valve. It controls the flow of the liquid Freon, giving it enough room to expand. When liquid Freon expands, it evaporates back into a gaseous state. Then it’s ready to begin the cooling process in your home all over again.
In the winter, the process reverses. When you ask your heat pump to warm up your home, it uses the compressed Freon to carry warmth into your home where it can heat the indoor air. As that happens, the Freon’s pressure drops, and it gets cold. Since the Freon’s temperature will drop below that of the outdoor air — even in the middle of winter — it will still absorb heat energy in the outdoor air to carry back into your home.
There’s Heat in Cold Air?
That part of the process is what seems to cause the most confusion. It’s because humans perceive heat and cold within a narrow range. In reality, though, there’s some heat energy still in the air all the way down to absolute zero. In case you’re wondering, absolute zero is approximately −459.67 degrees Fahrenheit.
Of course, we don’t notice much heat in the air once it gets to around 32 degrees Fahrenheit or below outside. A heat pump, however, will still be capable of extracting heat energy from the cold winter air. That’s because the Freon’s temperature is far lower than the outdoor air temperature, even in the winter. The lower the outdoor temperature gets, though, the less efficient a heat pump becomes.
That’s the reason why most modern heat pumps come equipped with small electric heaters that can augment your heat supply when the outdoor temperature goes well below freezing. Even then, heat pumps still use far less energy than comparable traditional heating systems. In other words, they’re cheaper for you to operate even when they’re not running at peak efficiency. It’s also worth noting that the latest heat pumps can even maintain peak efficiency at temperatures as low as 0 degrees Fahrenheit —making them even more attractive as heating systems in our area.
Consult the Heat Pump Experts
Now that you understand how and why heat pumps use Freon, perhaps you’re ready to learn even more about them. Heat pumps make an excellent and budget-friendly upgrade to traditional heating and cooling systems. Here in the Pacific Northwest, they can save you a great deal of money on your winter heating costs. The experts here at Apollo Plumbing, Heating & Air Conditioning know all there is to know about the latest heat pump technology and are happy to answer any questions you have.
We’re a family-owned and operated business that’s served the area since 1984, so we have the kind of experience that our competitors can’t match. Plus, we install, maintain, and repair heat pump systems for both residential and commercial customers. That means we’re a one-stop shop for your heating and cooling needs both now and into the future.
So, if you’re ready to find out how a heat pump can be the answer to your heating and cooling needs, contact Apollo Plumbing, Heating & Air Conditioning today!
