If you own a home here in Mesa, AZ, there’s a good chance you’re interested in having the most efficient HVAC system possible. They can both heat and cool your home, eliminating the need for a separate furnace and air conditioner. If you’ve gone looking for one, there’s no doubt you’ve come across heat pumps. However, heat pumps are often misunderstood, and plenty of misinformation about them is circulating online. That can lead you to question whether or not a heat pump is a good HVAC solution for your Mesa home. So, here’s everything you need to know about heat pumps to make a well-informed decision on whether or not to buy one as your home’s next HVAC solution.

What Is a Heat Pump?

Although it may seem like heat pumps recently appeared out of nowhere, they’re far from new. Heat pumps date back to the mid-1850s and have served various buildings and homes’ heating and cooling needs since then. Of course, they didn’t gain much traction among American homeowners until the energy crisis in the 1970s made HVAC energy efficiency a priority for most people. The problem was that heat pump technology wasn’t yet sufficiently advanced to make heat pumps a practical option everywhere, especially in places with extremely cold winters.

Heat pumps are mechanical devices that allow you to collect heat in one location, transport it elsewhere, and release it. They rely on the same kind of technology you’ll find in your kitchen refrigerator or a standard air conditioner. In fact, modern heat pumps are quite similar to air conditioners, except that they include a reversing valve that allows them to also heat your home in the winter.

How Heat Pumps Work

Heat pumps rely on the refrigeration cycle to collect and transport heat from place to place. They manipulate the refrigerant’s pressure, phase, and temperature to allow it to alternately absorb heat and then release it elsewhere. Transporting heat in that way is relatively simple in the summer. However, it’s often harder for most people to grasp how a heat pump works when it’s cold out.

In the winter, a heat pump collects available heat energy from the outside air and brings it inside to heat your home. The process begins when the heat pump runs its liquid refrigerant through an expansion valve, which lowers its pressure. Doing that makes the refrigerant much colder—as low as -15 degrees Fahrenheit in some cases—and also lowers its boiling point.

Next, the cold liquid refrigerant passes through a large heat exchanger in the heat pump’s outdoor unit. There, a large fan blows outside air across the heat exchanger. As that happens, the refrigerant warms up by absorbing heat from the air. As long as the refrigerant is colder than the air temperature, it will continue absorbing heat. Eventually, the refrigerant’s temperature reaches its boiling point, which turns the refrigerant into a warm vapor.

The warm refrigerant vapor then moves to the heat pump’s compressor. There, the compressor increases the refrigerant’s pressure, which also increases its temperature. Depending on the refrigerant’s starting temperature, it may reach up to 130 degrees Fahrenheit at this stage. After passing through the compressor, the now-hot refrigerant vapor travels into your home and through another heat exchanger.

This time, another large fan circulates your home’s indoor air across the heat exchanger, warming the air up to heat your home. When the refrigerant releases enough heat energy, it condenses into a high-pressure liquid. At that point, it can travel back outside and to the expansion valve to begin the process again. In the summer, the process works exactly the same, except in reverse, courtesy of the heat pump’s reversing valve.

The Fascinating Science Behind Heat Pumps

You may be wondering how heat pumps can extract heat from the air when it’s cold outside. The explanation lies in a few scientific principles that allow heat pumps to work. The most important among these is a particular part of the second law of thermodynamics. It states that heat will spontaneously move from warmer substances to colder substances. This is the same reason why ice cubes melt when you put them in hot water. In that case, the heat energy from the hot water is transferred into the ice cube until it reaches its melting point.

That scientific principle is only half of the equation, though. The second part is that the outside air always contains heat energy, even on very cold days. The outside temperature would need to reach −459.67 degrees Fahrenheit before no heat energy is left in the air. Therefore, as long as the heat pump contains a refrigerant capable of reaching a colder temperature than the outside air, it can collect heat.

The final bit of interesting science involves the relationship between the pressure, temperature, and boiling point of substances. Generally, when you lower the pressure on a liquid or a gas, it gets colder, and its boiling point drops. This is the same reason you must modify certain recipes when you cook at higher altitudes. The inverse happens when you increase the pressure on a liquid or a gas. The temperatures involved in this process change depending on the properties of the substance. This is why heat pumps use specially designed refrigerants capable of such wide temperature variances. If they used water or something similar instead, it would freeze long before it could pass through the heat exchanger to do its job.

So, Is a Heat Pump a Good Idea in Mesa?

Saying that a heat pump is a good idea here in Mesa is a massive understatement. This is because heat pumps operate most efficiently in winter climates that don’t drop too far below freezing. In our kind of climate, a heat pump can operate at up to 400% efficiency during most winter days. And they’re also tremendously efficient in the summer, too. The average heat pump on the market today has a SEER rating of 20 or higher, putting heat pumps among the most efficient cooling options you can buy. That all-weather efficiency can reduce your home’s energy costs by up to 40%!

Plus, there are now some very generous federal tax credits and subsidies that can make purchasing a heat pump significantly cheaper. Under the Inflation Reduction Act (IRA), you might qualify for a tax credit worth up to 30% of the heat pump cost up to a maximum of $2,000. And this year, another provision of the IRA will kick in to offer point-of-sale rebates for heat pumps of up to $8,000, depending on your household income.

Your Local Heat Pump Specialists

By now, you shouldn’t be wondering if heat pumps are a good idea in Mesa anymore. You should be wondering how soon you can install one in your Mesa home. For that, count on Honest Air Conditioning. We’ve served homeowners here for over 36 years, offering HVAC installation, repair, and maintenance services, as well as indoor air quality solutions. We’re Better Business Bureau accredited with an A+ rating and have a sterling reputation for customer service and workmanship. We even offer financing options on approved credit if you need help affording a new heat pump. So, when you’re ready to upgrade your Mesa home to a new energy-efficient heat pump, call Honest Air Conditioning right away!