Geomax - Geothermal Operation
Geothermal operation: geoexchange overview
A geothermal heating and cooling system (sometimes referred to as geoexchange or ground source heat pump) uses the consistent temperature of the earth to provide heating, cooling and hot water for both residential and commercial buildings.
 Geoexchange heat amplifiers extract stored solar energy from the earth to heat your home and hot water. In the summer, geothermal units put the heat from your house back into the earth.
The system is comprised of a water-source heat pump inside the building which is connected to loops of polyethylene pipes installed below ground level. Other components include a storage buffer water tank, a control panel and a delivery system, typically radiant floor tubing or forced air ducts.
Geothermal Operation: Closed loops - which can be buried horizontally in 6 foot deep, 100 foot long, 3 feet wide trenches; vertically in drilled holes 150-300 feet deep into the ground; or submersed in a pond - have liquid pumped through them to extract or transfer heat below the earth's surface.
Geothermal Operation: Open loops- pump water form sources such as lakes, streams or wells where the water is returned after running through the heat pump.
Geothermal Operation: Heating
Geothermal Operation: In the heating mode, the water circulating in the earth loop is colder than the surrounding ground. This causes the water to absorb energy, in the form of heat, from the earth. The water carries this energy to the heat exchanger in the pump. In the heat exchanger, refrigerant absorbs the heat energy from the water. The water now leaves the heat exchanger at a colder temperature, and circulates through the earth loop to pick up more energy.
 The refrigerant gas, which contains energy gained from the earth loop, travels from the heat exchanger to the compressor. In the compressor, the refrigerant temperature rises to 160°. From the compressor, the superheated refrigerant travels to the air heat exchanger. Here, the heat pump's blower circulates air across the air coil, increasing the temperature of the air, which is blown through ductwork to heat the home. After refrigerant releases its heat energy to the air, it then flows to the earth loop heat exchanger to start the cycle again.
Geothermal Operation: Cooling
Geothermal Operation: In the cooling mode, water that circulates in the earth loop is warmer than the surrounding ground. This causes the water to release energy, in the form of heat, into the earth. The water, now cooler from traveling through the ground now flows to the heat exchanger in the heat pump. In the heat exchanger, hot refrigerant gas from the compressor releases its heat into the water. This causes the water to increase temperature, which it releases to the ground.
 The refrigerant, which has released its heat energy and became a cold liquid, now travels to the heat exchanger. Here the heat pump's blower circulates warm, humid air across the cold air coil. The air is then blown through ductwork to cool the home. The refrigerant in the air coil picks up the heat energy from the air, and travels to the compressor. When the refrigerant leaves the compressor, it then flows to the earth loop heat exchanger to start the cycle again.
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