How Does a Heat Pump Work in the Winter?

All over Iowa, homeowners are looking for an energy-efficient HVAC system for their homes, and many are choosing heat pumps. Since heat pumps resemble air conditioners, many people think that heat pumps are for cooling their homes only. However, heat pumps can also provide heat to your home in the winter. The expert team at Novak Heating, Air, and Duct Cleaning in Cedar Rapids, IA has the answers to all your heat pump questions. If you’ve ever wondered “how does a heat pump work in winter,” we’ve got you covered.

How Do Heat Pumps Work in the Summer?

There are two kinds of heat pumps, but they both work the same way. Heat pumps work by following the laws of thermodynamics. Heat flows naturally from high temperatures to colder temperatures. The two types of heat pumps are air source heat pumps and ground source heat pumps. Air source heat pumps move heat between the air outside a home and the air inside a home, while ground source heat pumps rely on coils that transfer heat from the consistent temperature of the earth.

A heat pump is composed of an indoor unit and an outdoor unit. Each unit has coils inside that are connected between the indoor and outdoor units. If you’ve ever looked at the back of your refrigerator and have seen the coils behind it, they are very similar to what you might see inside your heat pump. In the summer, the interior coils work as an evaporator, absorbing heat from inside and releasing it outside, while the exterior coils condense the hot air to make it cool and transfer it inside. 

How Do Heat Pumps Work in the Winter?

In the winter, even though it’s much colder, an air source heat pump can still pull heat from the cold air. Heat pumps work in the winter by reversing operation. The outdoor coil becomes the evaporator and the indoor coil becomes the condenser.

The indoor coil warms the air with the refrigerant. Even though “refrigerant” sounds like something that would make things colder, it can actually heat the air too. Despite the cold temperatures outside, the refrigerant is actually so cold that it can absorb heat from the outside air and warm it up. The warm refrigerant then goes inside where it is condensed, and then the warm air is transferred to your home. 

Are Heat Pumps a Reliable Heating System for Winters In Cedar Rapids, IA?

You may have heard that air source heat pumps are not reliable or efficient in the extreme cold, and that they are best suited for warmer climates. While heat pumps are definitely more popular in warmer climates, recent advancements in technology have improved the heat pump’s efficiency in the winter, making them ideal for colder climates too. If we didn’t think heat pumps were a good idea in Cedar Rapids, we wouldn’t install them in so many homes.

An important thing to remember about your heat pump unit in the winter is to watch out for ice accumulation inside your outdoor unit. Occasionally you might notice that your heat pump is in “defrost” mode. This is a way that the heat pump keeps ice from accumulating. When defrost mode kicks on, the coils run to make the heat pump the proper temperature. It usually takes about 10 minutes to heat up. If you’ve noticed that your heat pump is in defrost mode for a long time, or goes into defrost mode frequently, that is a sign that your heat pump needs help. Try changing the air filter, and if that doesn’t help, call Novak for heat pump service.

Call Novak for Heat Pump Service

If your heat pump is frequently switching into defrost mode, or is not getting up to the set temperature, call Novak right away. We can inspect and repair heat pumps and get them working to make your home comfortable again. Call Novak for heat pump repairs and heat pump maintenance in the Cedar Rapids, RobinsMarionNorth Liberty, or Hiawatha, Iowa areas today.

Why You Should Pay Attention to Your Furnace’s AFUE Rating

When shopping for a new furnace, you’re going to have a lot of numbers thrown at you about the furnace’s performance. One of these numbers is the furnace’s AFUE rating. AFUE stands for annual fuel utilization efficiency and is a measurement of the furnace’s efficiency. It’s important to pay attention not only to the furnace AFUE rating but also to understand how it is calculated so you can make the right purchase for your home.

The furnace experts at Novak Heating, Air, and Duct Cleaning are here to help you not only find the best furnace for your home but install it and maintain its efficiency throughout its life. Trust us, your only Carrier Factory Authorized Dealer in Cedar Rapids, IA to set you up with some of the best furnaces in the business.

What Is an AFUE Rating?

AFUE is the energy-efficiency standard for all heating units manufactured in the United States. A furnace AFUE rating is similar to the mile-per-gallon rating on your car. AFUE measures the percent of heat produced for every dollar of fuel consumed. The higher the AFUE rating, the more efficient your furnace is.

When your furnace heats your home, gasses need to escape through an air vent or a chimney. This is necessary to prevent natural gas from filling up your home. Another factor that contributes to AFUE ratings is the type of burner used during the heating process. AFUE ratings do not account for leaks in ductwork. It’s a good idea to call Novak for air duct sealing, cleaning, and repairs before installing a new furnace to make sure it is working as efficiently as advertised.

According to, furnaces with an AFUE rating of 90%-98.5% are considered high efficiency. A mid-efficiency furnace has an AFUE rating of 80%-83%. An AFUE rating lower than this is considered low efficiency. 

How Is a Furnace’s AFUE Rating Calculated?

Now that we know what an AFUE rating is, let’s see how it is calculated. The AFUE rating is derived by finding the total annual heat output in BTUs divided by the total energy input in BTUs, multiplied by 100. The formula looks like this:

AFUE = (total annual heat output in BTUs / total energy output in BTUs) x 100

BTUs, or British Thermal Units, is a measurement that shows how much energy your furnace uses to create heat. A professional technician can use sensors to determine the heat output of your furnace.

So when you’re looking at AFUE ratings, think of it in terms of money. If a furnace has an AFUE rating of 100%, that means that all of the money that goes into heating your home is converted directly into usable heat. An AFUE rating of 85% means that 85% of the money you pay for heating is getting used, while 15% is wasted on escaped heat. This is why it’s important to pay attention to your furnace’s AFUE rating so you can see how much money you’re potentially wasting on heat. 

Other Things to Consider When Looking at New Electric or Gas Furnaces

While you might think that you should just go out and buy the furnace with the best AFUE rating, there are a few catches. For one, most high-efficiency furnaces are electric, not gas. This could make your electricity bills rise immensely. Pay attention to the fuel source type of any furnace you’re considering purchasing. High-efficiency furnaces also tend to be more expensive. Although you might love the energy savings, there’s a chance a high-efficiency furnace might be out of your budget.

Also remember that your furnace’s efficiency depends on how well it is maintained. Your AFUE rating won’t stay consistent for its whole life if you don’t have your furnace inspected and cleaned once a year. Be sure to schedule annual furnace tune ups with Novak every fall. 

Call Novak to Learn More About Furnace AFUE Ratings

When you’re ready to purchase a furnace or heating system, talk to the HVAC experts at Novak. We can find you an electric or gas furnace with the right furnace AFUE ratings to keep your furnace running efficiently. Call Novak today to schedule your new furnace installation.