Geothermal water source heat pump systems have rapidly gained popularity for residential and commercial applications because of their high efficiency, low carbon emissions and low life cycle costs. While their popularity is somewhat new, geothermal systems have been around for more than 30 years and have been applied in a multitude of applications including offices, schools, healthcare, recreational facilities, apartments, condominiums and single family residences. Both the U.S. Department of Energy and Environmental Protection Agency have long recognized geothermal systems as being among the most environmentally friendly, energy saving systems available for heating and cooling buildings.
With this relatively newfound popularity has come a multitude of benefits that have made the economics of installing a geothermal system more attractive than ever:
Mammoth has been providing water source heat pumps for nearly 50 years, making us one of the earliest providers of both standard and geothermal units. Known for their compact size, quiet operation and quality construction, Mammoth offers a complete line of horizontal, vertical, water-to-water and make-up air units from ½ to 70 tons for commercial and high-rise residential applications. We can provide you with standard units that incorporate advanced features such as FANWALL TECHNOLOGY® or digital scroll compressors, or advanced units that provide super high efficiency, ultra-quiet operation, high efficiency filtration and more.
Vertical Closed Loop (ARI 330 / ISO 13256-1)
Geothermal system is ideally suited for projects with minimum available space, vertical bore holes are drilled150 to 400 feet deep depending on design considerations necessary to condition the building. A plastic polyethylene supply/return pipe is inserted into the holes and wells are connected in a parallel reverse return arrangement to allow water to circulate evenly throughout the bore field. Loop temperatures range from 37°F to 95°F. Experienced designers should be used to determine the number and depth of bore holes.
Horizontal Closed Loop (ARI 330 / ISO 13256-1)
Similar to a vertical loop system except that a series of parallel loops are installed in trenches approximately 5 feet below the ground and then back filled. The piping may be installed using a “four-pipe” or “six-pipe” design. This design is well suited for applications where physical space is available – between 1,500 and 2,000 square feet/ton of cooling is required – or where bore drilling is prohibitive. Horizontal loops are usually not used in urban areas due to the limited availability and high cost of land.
Surface Water Closed Loop (ARI 330 / ISO 13256-1)
Geothermal system where the loop is directly installed in a lake or pond near the building (natural or constructed for aesthetic or drainage reasons), making it an extremely efficient , cost effective application. Bundled polyethylene coils are used in a reverse return design. Experienced designers should be used to ensure that the body of water will meet building loads. Debris problems from flooding or the need for public access may limit the use of this application.
Open Loop Well Water (ARI 325 / ISO 13256-1)
Systems use ground water to remove or add heat to the water loop. Typically used in regions where ground water is plentiful. Water is typically discharged back to the aquifer. Major benefit is the constant well water temperature, approximately 50°F, which provides very efficient operation at a relatively low installed cost. An intermediate heat exchanger is added in many cases to isolate the loop serving the units from the well water to reduce maintenance costs. This system usually has supply wells and return wells. Some states have requirements on the depths of return wells that must be approved by the U.S. Environmental Protection Agency. Water should be tested and strainers are typically required as poor water quality can increase heat exchanger scaling and suspended solids can lead to heat exchanger erosion.
If your application prohibits the use of a geothermal system due to space constraints or other limitations, you can still benefit from the high efficiency of a water source heat pump system. Standard boiler/tower systems are the most widely installed water source heat pump systems, offering high efficiency versus conventional HVAC systems and an economical installed cost.
This system – also called a standard, conventional or water loop system – uses a two pipe water circulating system to add, remove, or transfer rejected heat to other units throughout the building. The system is not geothermal because it typically uses a natural gas or electric boiler located in a mechanical equipment room to provide heat. A cooling tower is used to dissipate waste heat. This system is typically the lowest cost of the loop options.
For more information on how we can support your water source heat pump applications, please contact your local representative.