Which HVAC system uses underground temperatures as an operating factor?

Which HVAC system uses underground temperatures as an operating factor?

• A. Geothermal heat pump
• B. Air-source heat pump
• C. Conventional furnace
• D. Water heater

Answer: (A)

Geothermal heat pumps use underground temperatures as an operating factor. A loop of pipe is buried in the ground, where temperatures stay relatively constant year-round. In heating mode, heat is drawn from the ground into the refrigerant; in cooling mode, heat is transferred from the building into the ground. That steady underground temperature makes the system more efficient than others that rely on outdoor air or combustion. Air-source heat pumps depend on outdoor air and lose efficiency in cold weather; conventional furnaces burn fuel; water heaters provide domestic hot water and don’t use underground temperatures.

Geothermal heat pumps use underground temperatures as an operating factor. A loop of pipe is buried in the ground, where temperatures stay relatively constant year-round. In heating mode, heat is drawn from the ground into the refrigerant; in cooling mode, heat is transferred from the building into the ground. That steady underground temperature makes the system more efficient than others that rely on outdoor air or combustion. Air-source heat pumps depend on outdoor air and lose efficiency in cold weather; conventional furnaces burn fuel; water heaters provide domestic hot water and don’t use underground temperatures.