Open loop geothermal systems use water from a well. If there is sufficient water quantity and water quality, the home’s water may well serve a dual purpose and provide the water for domestic household purposes as well as for the geothermal system. There will be a discharge of water to a drain, ditch, stream or pond.
Well water is pumped from the pressure tank to the geothermal unit and heat is either extracted from it (heating) or added to it (cooling). There is no contamination or change to the water. Geothermal systems require 1.5 to 2 gallons per minute per ton of capacity. Most homes will use between 5-8 gallons per minute while the geothermal system is operating. Because the home’s water well can serve a dual purpose, an open loop system can provide the lowest installation cost for a geothermal system.