1. Geothermal Heat Pumps How Do They Work? Troubleshooting

2. It’s Not This…

3. What Is GeoExchange? Heat pump technology Heat pump technology Electrically powered Electrically powered Uses a closed or open ground loop as source Uses a closed or open ground loop as source Provides heating, cooling and hot water Provides heating, cooling and hot water

4. How Does It Work? All day long, 365 days a year the earth stores the energy it receives from the sun. All day long, 365 days a year the earth stores the energy it receives from the sun. 48% of our sun’s energy that reaches our planet is absorbed into the ground. 48% of our sun’s energy that reaches our planet is absorbed into the ground. In Colorado, the earth’s temperature 6 feet underground remains 50º-55º year ‘round. In Colorado, the earth’s temperature 6 feet underground remains 50º-55º year ‘round.

5. Three Sub-Systems The Ductwork (or Radiant Floor) The Ductwork (or Radiant Floor) Air Return Air Return Air Supply Air Supply The GeoExchange Unit The GeoExchange Unit Compressor Compressor Pumps Pumps The Ground Loop The Ground Loop Filled with a heat transfer fluid Filled with a heat transfer fluid Because of their rugged construction and by not being located outdoors, GeoExchange systems can reduce maintenance costs by 40-60%. Because of their rugged construction and by not being located outdoors, GeoExchange systems can reduce maintenance costs by 40-60%.

6. Heating Mode Operation

7. Cooling Mode Operation

8. The Heating Cycle Source: IGSHPA Closed Loop/Ground Source Heat Pump Systems

9. How Does It Work? Refrigerants are the key. Refrigerants are the key. Refrigerants have the ability to get extremely cold while remaining flow-able. Refrigerants have the ability to get extremely cold while remaining flow-able. Extremely cold things (20 F) can “harvest” heat from lukewarm things (55 F). Extremely cold things (20 F) can “harvest” heat from lukewarm things (55 F). GeoExchange systems are “heat movers”. GeoExchange systems are “heat movers”. They do not create heat. They move it from one place to another. They do not create heat. They move it from one place to another.

10. How Does It Work? Huh? If the ground is only 55 degrees, how does it heat my building to 75 degrees? Huh? If the ground is only 55 degrees, how does it heat my building to 75 degrees? It’s basic refrigeration. It’s basic refrigeration. Think not in terms of temperature. Think not in terms of temperature. Think in terms of heat content. Think in terms of heat content. How does your air conditioner work? How does your air conditioner work? If it’s 90 degrees outside, how does it cool your house to 70 degrees? If it’s 90 degrees outside, how does it cool your house to 70 degrees?

11. A Furnace vs. Your Backyard Small block of stuff. Small block of stuff. 50 lbs. 50 lbs. 120 degrees F. 120 degrees F. Huge block of stuff. Huge block of stuff. 5,000,000 lbs. 5,000,000 lbs. 55 degrees F. 55 degrees F. Which One Has More Heat?

12. How Does It Work? In fact, a GeoExchange unit concentrates the heat energy from the ground. In fact, a GeoExchange unit concentrates the heat energy from the ground. This brings the temperature up to a more useable level. This brings the temperature up to a more useable level. Advanced fact: Advanced fact: What really happens is the heat from the ground causes the refrigerant to evaporate. What really happens is the heat from the ground causes the refrigerant to evaporate. Changing a substance from liquid to vapor results in a large transfer of energy; called the latent heat of vaporization. Changing a substance from liquid to vapor results in a large transfer of energy; called the latent heat of vaporization. This energy moves from the ground to the refrigerant. This energy moves from the ground to the refrigerant.

13. Troubleshooting Macro Level Problems Macro Level Problems Poor Comfort Poor Comfort High Operating Cost High Operating Cost Poor Reliability Poor Reliability Micro Level Problems Micro Level Problems Heat Pump Unit Breaks Heat Pump Unit Breaks

14. Troubleshooting Macro Level Problems Macro Level Problems Load Calculation Load Calculation Ground Loop Design Ground Loop Design Distribution System Design Distribution System Design Electric Service Electric Service

15. Troubleshooting Micro Level Problems Micro Level Problems Moving Parts Moving Parts Fan/Pump (Load) Fan/Pump (Load) Pump (Source) Pump (Source) Compressor Compressor Metering Device Metering Device Reversing Valve Reversing Valve Controls Controls Thermostats Thermostats Control Boards Control Boards Switches/Relays Switches/Relays Refrigerant Leaks Refrigerant Leaks Can be tested easily, finding is another matter Can be tested easily, finding is another matter