In this guide to geothermal heat pump installation, we’ll explain what a geothermal system is and explain its benefits, the types available, and the steps to planning and installation. Sky Heating & Air Conditioning can help you with every step of the process. The type of system you choose depends on your needs. There are many factors to consider. If you’ve never delved into this technology before and are looking for an upgrade, here’s a resource to help provide clarity and insight.
What Is a Geothermal Heat Pump?
It is a system that draws heat from the Earth and extracts this heat to provide warmth in your home. It does so without using fossil fuels. Also called a ground-source, GeoExchange, earth-coupled, water-source, or earth-energy heat pump, it can heat or cool your home. Rather than generating heat like a furnace, it moves heat from one place to another. Heat is transferred from the ground using a series of coils known as geothermal ground loops.
Benefits of Geothermal Heat Pump Installation
Air-source heat pumps are more common, but geothermal systems are more energy efficient. That’s because the temperature underground is more consistent than air temperatures. A geothermal heat pump can reduce energy consumption by 25% to 50% compared to an air source system, which results in a substantial drop in cooling costs.¹ Other benefits include:
- Return on Investment: A geothermal system costs more to install than other HVAC equipment. However, the cost savings become apparent just a couple of years after installation. Tax benefits also contribute to savings.
- Eco-Friendly: Geothermal heat pumps use less energy and lower your carbon footprint. They also don’t release harmful greenhouse gases and other pollutants.
- Improved Comfort/Indoor Air Quality: A geothermal system is highly effective at heating or cooling a space. It also has superior air purification and dehumidification capabilities compared to a traditional air conditioner.
- Safety: No combustible materials are used by a geothermal system, so it’s much safer to operate and clean than a traditional HVAC unit.
- Quiet: Geothermal heat pumps don’t make as much noise as other AC or heating equipment when they turn on and off.
- Can Be Installed Anywhere: A geothermal system can be installed in a newly constructed home or as a retrofit (and can be connected to existing ductwork).
- Longer-Lasting: Indoor components can last as long as 25 years, far outlasting other types of HVAC systems. However, the ground loop system can last up to 50 years.
Types of Geothermal Heat Pumps
When planning for geothermal heat pump installation, it’s important to weigh the different types of units. The best type depends on the size of your home, the local climate, and soil conditions. Installation costs can influence your decision too. The most common types of geothermal heat pump systems include:
- Horizontal Loops: Layered coils and pipes are laid in four- to six-foot trenches and require sufficient ground space (about 400 square feet). Horizontal ground loops are generally suited for homes of approximately 2,000 square feet. The trenches aren’t very deep, so a horizontal system is generally cost-effective to install.
- Vertical Loops: If you have a limited amount of ground space or shallow soil, a vertical loop can be a better option. It requires four-inch diameter holes to be drilled 100 to 400 feet into soil and bedrock. There’s little disturbance to the landscape, but installing vertical geothermal systems is generally more expensive.
- Pond/Lake Loops: A supply pipe runs from the building to a water source that meets water quality, volume, and depth criteria. The coils are buried at least eight to 10 feet to prevent them from freezing. They’re also anchored onto racks to help generate heat.
- Open Loops: These water source heat pumps circulate well or surface water directly through the system to facilitate heat exchange. After circulating and delivering heat to your home, the water is pumped back into the well or discharged at the surface. The system requires a relatively clean water source and must meet local codes for groundwater discharge.
How to Prepare for Installation
Site evaluation is a crucial step in preparing for geothermal heat pump installation. Unlike with other HVAC systems, ground conditions are a significant factor. Your local installer will need to consider the geology around your home; the heat transfer properties of the soil determine the amount of piping needed (the less effective at heat transfer the soil is, the more pipes will be needed).
Hydrology is another factor. The quality, depth, and volume of a ground or surface water source help determine the type of system to install. Depending on hydrological conditions, installing a geothermal heat pump can risk groundwater contamination, aquifer depletion, and other environmental hazards. Lastly, the installer will consider land availability, where underground utilities are located, and your landscaping.
Using this information, they’ll determine the ideal location for the system. They will also evaluate your home and perform a Manual J load calculation. Its square footage, insulation, number of windows and doors, and how many people live there are used to calculate the size of the system and the amount of energy needed to provide enough heating and cooling. They’ll also help acquire permits and approvals from local officials.
The Installation Process
Once the site evaluation, load calculation, and planning process are complete, your local contractor will proceed with the geothermal heat pump installation. In general, the installation process entails:
- Trenching/Drilling/Ground Loop Installation: Trenches are dug to install horizontal ground loops and large drilling machinery is used to create holes for vertical loops. The piping will be installed in the ground before the contractor proceeds with the rest of the system.
- Ductwork Installation: If your home doesn’t have ductwork or existing ducts are outdated, new ductwork will be installed and run throughout your home. It will be connected with the heat pump’s ground loops.
- Heat Pump Installation: Your old air conditioner, furnace, or boiler will be removed and the heat pump will be installed in its place. The technicians will connect it to the ground loop and your ducts.
- Electrical Connections: The heat pump system will be wired and connected to your electrical system. Upgrades such as rewiring or installing a higher capacity breaker panel may be necessary. The heat pump is then tested to ensure it operates safely and effectively.
Cost/Affordability
On average, a 3-ton geothermal heat pump costs $7,500 to install. Systems cost about $2,500 per ton of capacity, but that doesn’t include drilling and installation costs. Since every home’s requirements are different, costs can vary considerably. However, you can save hundreds of dollars per year in utilities and may qualify for tax credits, rebates, and other opportunities to save. With energy savings considered, the system can pay for itself within a few years.
Contact Sky Heating & Air Conditioning
If you’re looking for a more efficient, environmentally friendly way to heat and cool your home, Sky can install a geothermal heat pump. We consider every factor when planning installation projects in Oregon homes. Since 1979, we’ve been delivering high-quality workmanship from licensed geothermal specialists. To learn more or schedule geothermal heat pump installation in the Portland area, call (503) 676-6945.
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