Geo-Flo NP2 Non-Pressurized 2-Pump Flow Center, (2) Grundfos UPS26-99 3-Speed, 208-230V, Flo-Link

Geo-Flo’s NP Series non-pressurized flow centers are the only non-pressurized flow centers in the industry that provide a truly closed-loop system with controlled pressure and vacuum relief and incorporate 3-way valves for system flushing.  The pressure relief valve allows the system to be pressurized to 13 PSIG, which no other non-pressurized product can claim.  This is important since geothermal HDPE loop pipe contracts when the system is in heating mode increasing system pressure.  Further, our NP products include a vacuum relief valve (built into the cap) that is closed during normal operation, but opens when the system pressure drops below atmospheric pressure.

Geo-Flo’s 3-way flushing valves with Flo-Link double O-ring connections are built into the NP series flow center.  By incorporating flushing valves into the flow center, the ground loop may be flushed without adding external flush ports, saving installation time and additional cost. 

For help calculating the pressure drop of your geothermal system and selecting the appropriate flow center, try GeoDesign Pro.