Our PN 3565, 0-100 PSI pressure gauge assembly is used to measure static pressure and/or differential pressure (delta-P) in a system via a Pressure-Temperature (PT) plugs. For static pressure measurement, insert the needle into a PT plug when the system pump is not running. To measure delta-P, ensure that the system pump is running then insert the needle into one PT plug, record the value, and repeat for the second PT plug. The differential pressure between the two measurement locations is the difference between the two values recorded. Geothermal and water source heat pump systems should have heat pump elbows with PT plugs on both the entering and leaving water/fluid connections. By determining the delta-P, which in this case is also known as the pressure drop across the unit’s heat exchanger, you can determine the fluid flow rate. Geothermal heat pump manufacturers publish a table of pressure drop versus flow rate for various entering water temperatures for each heat pump that they manufacture, so you simply need to look up your pressure drop to determine the flow rate.
The 2473 pressure gauge is used in our Geo-Gooser product is useful for rough static pressure measurements. The dial is too small to get a reasonably accurate pressure drop measurement and calculation.
| Part Number | Description | Photo |
|---|---|---|
| 2143 | PT Plug 1/4 MPT |  |
| 2144 | PT Plug 1/2 MPT |  |
| 2145 | Gauge Adapter 1/8" needle With Guard |  |
| 2473 | Pressure Gauge, 0-100 PSI, 2" Dial, 1/4 MPT |  |
| 2634 | Gauge Adapter 1/16" needle With Guard |  |
| 3565 | Pressure Gauge,0-100 PSI, 0-230 Feet of Head, 3.5" Dial, with 1/8" PT Adapter |  |
| 5171 | Pressure Gauge, 0-100 PSI, 0-230 Feet of Head, 3.5" Dial, 1/4" MPT |  |