January 21, 2021

You are tired of dealing with a furnace and the variable gas prices that go with it. You have heard great things about transitioning to a geothermal system, both in terms of operating costs and ecofriendliness. But you have also heard questions about how well these systems work during the coldest points of the Illinois winter. How does this system work, and will it be able to keep up with the bitter cold?

How Do Geothermal Systems Work?

To begin answering how well geothermal systems work in the bitter cold, you need to understand the basics of the system. The idea behind geothermal systems is that they use the heat from the ground rather than a burned fuel or electric heating element.

These systems cycle some form or coolant through pipes to absorb the warmth from the ground. That coolant then travels into the heat exchanger, where it warms the air moving through the heating system.

The piping for the coolant has to move through the ground below the frost line. So your contractor must be familiar with this to know the depth at which to lay the system. If you live near a body of deep water, you can also run the system through the water below the ice line.

The idea is that these deeper areas maintain a constant temperature throughout the year. The ground maintains a temperature between 50 and 60 degrees. However, the pressure in the coolant pipes causes the system to produce much greater temperatures.

What Are the Differences in Geothermal Systems?

There are two broad types of geothermal systems, with a total of four different specific types. The two broad categories are sealed and open systems. A sealed system is the most common and continues to circulate the same coolant throughout the system. An open system draws in water, usually from a well, circulates it, and then discharges it afterward.

Two of the sealed systems run the coolant lines through the ground. One system runs these lines horizontally, which means it requires more land to make it work. In this method, you will need to be able to bury the lines at least 4 feet down.

For people with smaller lots, they use a vertical system. In order to run the lines vertically, you have to be able to run the lines deep enough without running into bedrock or the water table. This would require a series of holes that descend 100 feet to 400 feet.

The third option for a sealed system is to run the coolant lines through the water. In these systems, the lines are run underground to the water. Then they are coiled on the bed of the water body. The key is that the water must be at least 8 feet deep for this to be effective during the winter.

What Happens in the Bitter Cold?

Even during the bitterly cold weather, geothermal heat pumps continue to work very well. This is because once you get about 10 feet below the surface, the ground maintains a constant temperature of about 55 degrees. So whether it is 100 degrees outside or -15 degrees, your pump should continue to run very effectively.

Do You Need a Backup Heating Source?

Some people suggest you need to maintain a traditional furnace or heating system as a backup for the extreme winter days. This all depends on if your heat pump is sized properly for your situation. If you have a properly sized system, then your geothermal system should be sufficient because of the constant temperature underground.

How Do You Size a Geothermal System for Illinois Winters?

There are two variables at play to determine what size geothermal system you need. The first is the size of your home, and the second is how cold it gets in your area. In Peoria, the lowest recorded temperature was -27 degrees in 1884. The coldest wind chill was set in 1983 at -52 degrees.

If you use these record temps to size your system, you ensure it will operate regardless of the outside temperature. Your authorized installer will take this and the size of your home to determine your proper system size. Ideally, your system would run continuously on the coldest day to keep your home comfortable. On less extreme days, it would cycle on and off like a normal furnace system.

Bratcher Heating & Air Conditioning, Inc. has provided trusted heating and cooling service to the Peoria area since 1983. Our team offers expert conversion of traditional systems to geothermal, in addition to installation, maintenance, and repair of all heating and cooling systems. Call to schedule your geothermal system consultation today.

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