Geothermal is by far the highest efficiency heating and cooling system available today. While the systems require up to three times more investment upfront than a conventional heating and cooling system the payback rate can be as much as three times faster when compared against the least efficient types of systems available today.
Geothermal works by tapping into very large low temperature heat sources such as the earth itself or water from a well, pond or other large sources. The earth under our feet and large volumes of water constantly maintain their temperature and measure from 40F to50F in most Northern U.S. Climates, the temperature of the ground at a depth of 30 feet or deeper remains very stable and the same holds true for well water sources as they too are very deep. As you approach the surface of the ground the temperatures will decrease in stability, the closer to the surface the greater the range, at 6 feet deep you can expect up to a 20 degree range in temperature. Other factors such as soil type and moisture saturation levels also effect the capacity of the soil to transfer that heat so these things also need to considered when designing a system.
The mechanics of the systems are relatively simple as they are essentially just a heat pump, a heat pump is an air conditioner that reverses itself. In other words a conventional A/C unit absorbs the heat from the home using the low pressure side of the refrigerant and releases that heat outside at the condensing unit or A/C unit using the high pressure side of the refrigerant. A heat pump just reverses the flow of the refrigerant so that the heat is absorbed from outside and released inside the home. The difference with geothermal is that instead of using the outside air it uses circulating water to either absorb or release the heat to or from the ground or the well water.
Ameri-Serv, Inc, Heating and Cooling sells Climate Master GeoThermal Systems and we can service and repair all brands and system types.
The systems take this circulated water and pump it through the geothermal unit at a specified flow rate depending upon the water temperature, this water flows through a heat exchanger which is normally two coiled pipes, one inside the other with the refrigerant flowing in the inner pipe and the water flowing through the outer pipe. The flow rate is crucial to the proper operation of the system and the temperature of the water can change the required flow rates. Most systems are set at one flow rate for all conditions and others self regulate this flow rate for changing conditions.
The well water systems typically will pump well water through the unit and inject it back into another well a sufficient distance away. The ground source system uses one of two methods, the first is by far the best choice and consists of deep bore holes, up to 300 feet or more, with either coiled or looped pipes extending down into the bore hole, these are the best because the temperatures are more stable the deeper you go and the water saturation levels are usually higher. The other type requires a lot of surface area and consists of trenches, 6 to 10 feet deep with the pipes looped in the trenches.
Both systems require the pipers to be filled with water and antifreeze and the amount of pipe or length depends on both the type of ground system used (bore holes or trenches), the soil temperature and conditions as well as the size of the geothermal system required to heat and cool the home. This ranges from 200 to 300 feet of pipe per ton of energy (1 ton = 12,000 btu's) and a typical home at around 1800 square feet takes about 3 to 4 tons of energy to properly heat and cool the home depending on the home's efficiency.
When considering a ground source system it is very important to place a lot of consideration into who installs the system, or more importantly, who designs the system. A qualified contractor will be able to tell you all the things discussed above and accurately estimate what it will take to make the system work. Most complaints about geothermal systems stem from improperly sized and installed systems. While sizing a system to the home is fairly easy the ground source side of the system is where the mistakes are usually made.
Geothermal works by tapping into very large low temperature heat sources such as the earth itself or water from a well, pond or other large sources. The earth under our feet and large volumes of water constantly maintain their temperature and measure from 40F to50F in most Northern U.S. Climates, the temperature of the ground at a depth of 30 feet or deeper remains very stable and the same holds true for well water sources as they too are very deep. As you approach the surface of the ground the temperatures will decrease in stability, the closer to the surface the greater the range, at 6 feet deep you can expect up to a 20 degree range in temperature. Other factors such as soil type and moisture saturation levels also effect the capacity of the soil to transfer that heat so these things also need to considered when designing a system. 
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