Zone valves are used to control the flow to a individual plumbing circuit (i.e. zone). In geothermal heat pump systems, they are used to control flow to the heat pump in either closed-loop or open-loop systems. Geo-Flo supplies Taco Zone Sentry and Belimo zone valves for close-loop systems. The Taco Geo-Sentry may be used for closed-loop systems or open-loop systems.
Flow regulators are used to control the volumetric flow rate of a fluid through a device such as a geothermal heat pump. Fixed orifice flow regulators are typically used in open-loop geothermal systems since they are relatively low cost, and the high pressure drop through the valve is not as big of concern since the open-loop well pump provides plenty of head capacity. Fixed orifice flow control valves should be used with caution or avoided in closed-loop systems since the high pressure drop through these valves may require a much larger circulation pump to achieve the required flow rate.