Flow Proving Switch (Differential Pressure)
Flow Proving Switch (Differential Pressure)

Accessories, Geothermal Accessories

Flow Proving Switch (Differential Pressure)

Geothermal accessory from Bosch.

  • Shuts down WSHP before hard lockout fault
  • No water flow through switch; thus no fouling or clogs
  • Easy connection to Bosch hose kits


Why choose Flow Proving Switch?

Flow Proving Switch (Differential Pressure) shuts down the WSHP before unit can go into hard lockout faults due to water flow issues (ie. High head pressure, etc.). Prevents the need to manually reset the WSHP. Features include: waterless flow detection, adjustable differential pressure range, and durable outer shell.

Physical Characteristics

Overall dimensions: 3.64” x 1.25” x 1.69”, ¼” FPT high and low tube/pipe connection, Maximum water pressure: 1000 psi, Maximum differential pressure: 200 psi, Maximum temperature: 2,000℉, Switch SPST (Normally Open), Electrical connections are jacketed (22AWG), Switch rating: 50W – 240 VAC/VDC – 3 amps.

Third-party Requirements

Some third-party materials are needed to install the switch external to the water source heat pump. We recommend the following to successfully install the Flow Proving Switch (Differential Pressure): 4 x ¼” flare nuts, 2 x ¼” copper tubing (2-4’ sections), 2 x ¼” male flare nuts (replaces the P/T plugs in the Bosch hose kits), and flaring tool.

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