Geothermal Systems
Open Loop Geothermal Systems
Open Loop Geothermal Systems
1-800-831-8883
Open Loop Geothermal Heat Pumps
Cushing and Sons has successfully completed dozens of open loop heat pump systems. Commonly in New England these are deep bedrock boreholes that will recirculate the water across a long length of bedrock. Commonly 80-125 lineal feet of water column is required per ton of heating capacity.
These wells will commonly deliver the water to the heat pump at 3 gallons per minute (GPM) per tom of heating equipment. Approximately 90% of the water that passes through the heat pump is discharged back into the well. The remaining 10% goes out to “bleed” and is commonly delivered to a dry well or discharge ditch. It is prefered that this water be discharged in such a manner as to be returned to the surfacial ground water.
These systems frequently will have a well head above grade – like a common water well. However, these wells are usually constructed differently than a normal water well, utilizing larger cast casing sizes than residential and large pump systems; all dependent on the size of the equipment to be supported.
Often, these wells are used for the potable water supply in a home where allowed.
Commonly, domestic heating/cooling systems have wells that are 400-500 feet deep, recirculating 15 GPM, bleed rates of 1.5 GPM, and have a 1.5 HP variable speed pump system. Commercial installations can have wells to 1,500 feet deep with 8″ casings, 4″ diffuser pipes, and pump sizes to 10 HP – moving 75 GPM with bleed rates uf 7.5 GPM.
Cushing and Sons can drill the well, perform the recommended pump drawdown testing, and install the permanent pump system to support the ground source heat pump (GSHP) system. We work with dozens of GSHP installers throughout New England and have worked with engineers in design and equipment recommendations.
Check our growing list of geothermal projects from around New England.