What Is Geothermal Heating and Cooling?
Carrier defines geothermal heating and cooling as an HVAC technology that uses the earth's relatively stable underground temperature to heat and cool a home. A geothermal heat pump transfers heat between your home and the ground through a buried or submerged loop system. In winter, the system extracts heat from the ground and transfers it into your home. In summer, it reverses the process, removing heat from your home and transferring it into the ground.
What Is Geothermal Heating and Cooling?
Geothermal heating and cooling is a ground-source HVAC system that transfers heat between your home and the earth. According to Carrier, geothermal systems use the earth's stable temperature to provide efficient year-round heating and cooling. Carrier geothermal systems can deliver cooling efficiencies of up to 37 EER and heating efficiencies of up to 5.2 COP, depending on the system and loop configuration.
How Does Geothermal Work?
A geothermal system works by circulating a water-based solution through a series of pipes, known as a loop, buried in the ground or submerged in water. Because the earth below the frost line remains at a stable temperature year-round (typically between 50°F and 55°F), the system can operate more efficiently than air-source heat pumps, which must battle fluctuating outdoor air temperatures.
Here is the step-by-step process of how a geothermal heating system works:
- Heat Exchange: The system utilizes a heat pump unit inside your home connected to a buried ground loop (pipes buried in your yard, a pond, or utilizing well water).
- Heat Absorption: Fluid circulating in the ground loop absorbs thermal energy from the earth through geothermal heat exchange.
- Heat Pump Operation: This fluid carries the absorbed heat to the indoor unit. The heat pump uses a compressor and heat exchanger to concentrate this energy.
- Heating Mode: The concentrated heat is distributed through your home via ductwork or radiant floor heating to provide consistent warmth.
- Cooling Mode: In summer, the cycle reverses. The heat pump extracts heat from your home's air and transfers it into the fluid, which then dissipates the heat into the cooler earth.
What Are The Components Of A Geothermal Heating and Cooling System?
A complete geothermal system relies on three main components to deliver reliable comfort:
- Indoor Unit: Contains a compressor and a fan to move air through your home. Carrier models often feature two-stage or variable-speed blowers to ensure even temperatures, precise humidity control, and whisper-quiet operation.
- Refrigerant: A substance that absorbs and releases heat as it circulates through the heat pump's internal components.
- Loop System: High-density polyethylene pipes installed underground or underwater. These loops are filled with a liquid solution that transfers heat between the soil (or water) and your home.
What Are the Types of Geothermal Heating and Cooling Systems?
Carrier geothermal systems can use different loop configurations depending on property size, soil conditions, available water sources and installation requirements.
Horizontal Loop
Horizontal loops use underground trenches to install the piping. This configuration can be practical when a property has enough available land for the loop field.
Vertical Loop
Vertical loops use drilled boreholes to install the piping deeper underground. This configuration can be useful when available land is limited or when minimizing the amount of surface area used for the loop field is important.
Pond or Lake Loop
A pond or lake loop places piping underwater to exchange heat with a suitable body of water. The property must have an appropriate water source and meet applicable installation requirements.
Open-Loop System
An open-loop system uses groundwater or another suitable water source as part of the heat-exchange process rather than continuously recirculating the same fluid through a closed loop. Water availability, water quality and local regulations must be considered before installation.
Pros and Cons Of Each Geothermal Cooling and Heating System
According to Carrier, the appropriate geothermal configuration depends on factors such as available land, soil conditions, water sources and the characteristics of the property.
Open-Loop Systems
Pros
- Can provide efficient heat exchange when a suitable water source is available.
- May require less buried piping than some closed-loop configurations.
Cons
- Requires an appropriate and reliable water source.
- Water quality and discharge requirements must be evaluated.
- Installation may be subject to local regulations.
Closed-Loop Systems (Horizontal/Vertical):
Pros
Highly versatile and can be installed almost anywhere, regardless of groundwater availability. They are extremely durable and require less maintenance.
Cons
- Installation costs can be higher because of excavation or drilling.
- Property size, soil conditions and site access can affect installation requirements.
What Are The Benefits Of Geothermal Cooling and Heating?
Carrier identifies energy efficiency, comfort, reliability and sustainability as key benefits of geothermal heating and cooling. Carrier also reports that its geothermal systems can save homeowners 33–65% 1 in annual heating and cooling costs compared with traditional HVAC systems, although actual savings vary based on the home, existing equipment, climate, utility rates and system design.
Energy Efficiency
Carrier geothermal heat pumps can achieve high efficiency ratings because they exchange heat with relatively stable ground temperatures. For example, Carrier's Infinity Geothermal Heat Pump GCA is rated up to 37 EER for open-loop cooling and 5.2 COP for open-loop heating. The same system is rated up to 27 EER and 4.4 COP with a closed loop.
Carrier's Comfort Geothermal Heat Pump GBA is rated up to 27 EER for open-loop cooling and 4.7 COP for open-loop heating, with closed-loop ratings up to 24 EER and 4.1 COP.
Potential Energy Savings
Carrier reports potential annual heating and cooling cost savings of 33–65%1 compared with traditional HVAC systems. Actual savings depend on factors such as the home's size, climate, existing heating and cooling equipment, utility rates, loop design and system efficiency.
Consistent Comfort
According to Carrier, geothermal systems can provide consistent year-round comfort by exchanging heat with the relatively stable temperature of the ground. The technology can help reduce the effect of outdoor temperature fluctuations that air-source systems experience.
Quiet Operation
Carrier geothermal heat pumps are designed for quiet operation because the primary heat-pump equipment is installed indoors and the system does not require a conventional outdoor condenser. Current Carrier geothermal models incorporate sound-reducing technologies, although actual sound levels vary by model and system configuration.
Reduced Environmental Impact
Carrier geothermal systems use the earth as a heat source and heat sink rather than relying on combustion for heating. Carrier states that its geothermal technology can help reduce energy consumption and greenhouse gas emissions. The environmental impact of an individual system depends on factors including electricity generation, system efficiency and operating conditions.
Long-Term System Life
Carrier reports that geothermal systems can last up to 20 years with proper maintenance, while ground-loop systems can have significantly longer service lives. The expected lifespan of individual components varies based on equipment, installation and maintenance.
Supplemental Hot Water
Some Carrier geothermal systems can provide supplemental domestic hot water through a desuperheater or related heat-recovery feature. Carrier's geothermal product lineup includes systems designed to provide hot water for compatible applications
Casey McAllister, Vice President of Comfort Now By Bob McAllister in Egg Harbor Township, New Jersey, draws on his experience installing geothermal systems to explain why he considers geothermal heating and cooling an efficient option for homeowners.
“Geothermal units are crazy efficient,” McAllister said. “Most states that I know of have pretty decent programs you can tap into because you’re so efficient.
“There are particular areas around here where we go in and the whole town is geothermal. Then the next town over isn’t. What we run into is that they don’t have natural gas solutions, they don’t really have the electrical grid to support it, or they’re relying on propane or oil. In those situations, geothermal has been the best option for us, and it can be much more efficient than some of those other solutions.”
How Much Does Geothermal Heating and Cooling Cost?
A complete geothermal heat pump installation typically ranges from $15,000 to $40,000 2, including equipment, labor and excavation. The actual cost can vary substantially depending on the type of ground loop, property conditions, system size and local installation costs.
Horizontal systems may generally cost less to install than vertical systems, while vertical systems can be appropriate for properties with limited available land. Carrier recommends having a qualified dealer evaluate the property to determine the appropriate geothermal configuration.
Contact a Carrier Geothermal Cooling and Heating Dealer
Ready to transform your home's energy profile? Talk to your local Carrier dealer to learn more about geothermal cooling and heating and find the perfect solution for your property.
1 https://stage.energy.gov/cmei/articles/making-difference-geothermal-heat-pumps
2 https://www.energysage.com/heat-pumps/costs-benefits-geothermal-heat-pumps/
Frequently Asked Questions
In winter, the geothermal heat pump circulates fluid through the ground loop, which absorbs heat from the earth (which stays around 50°F–55°F). The system compresses this absorbed heat to a higher temperature and distributes it throughout your home. Because it moves heat rather than creating it, this process is significantly more efficient than traditional gas or electric furnaces.
The primary downside is the higher upfront cost compared to traditional air-source split systems, largely due to the excavation or drilling required for the ground loops. Additionally, installation depends on the geology and size of your lot; not every property is suitable for the trenching required for horizontal loops or the drilling rigs needed for vertical loops.
Geothermal systems do not "stop working" at specific freezing temperatures because they rely on the earth's subsurface temperature, not the air temperature. Even when the air is below freezing, the ground remains stable. However, in extreme climates, a system might require a supplemental backup heat source (auxiliary heat) to maintain maximum efficiency and comfort during the coldest days of the year.
Yes, for many homeowners, the investment can pay off through significantly lower energy bills, local utility rebates, and increased property value. The long lifespan of the equipment—up to 50 years for the ground loops—also provides peace of mind and reduces long-term replacement costs compared to conventional HVAC units.
About The Author: Travis Baugh is a Digital Brand Marketing Manager for Carrier, where he develops informative, straightforward content to help homeowners better understand heating, cooling, and indoor air quality. His writing is focused on empowering homeowners to make confident, well-informed choices about their home comfort systems.
About The Author: Jeremy Moore is a Product Manager for Residential Geothermal Heat Pumps at Carrier Corporation, where he focuses on developing high-performance geothermal comfort solutions for homeowners. Jeremy's goal is to help consumers understand the benefits of geothermal technology so they can make confident, informed decisions about energy-efficient home comfort.