Backflow Preventer Pressure Loss
Pressure loss interpolated from manufacturer-published curves.
Example
You enter
- Device class RP
- Flow (gpm) 30
- Pipe size 1
You get
- Pressure loss 8.5 psi
Details, formula, and sources
Linear interpolation of manufacturer pressure-loss curves by device class (RP / DCV / PVB / AVB) and pipe size.
Manufacturer technical bulletins (Watts Series 909 RP / 909 DCV / 800 PVB / Series 8 AVB) by name.
Free at watts.com.
Estimate. AHJ and licensed plumber / gas fitter govern. Verify against the IPC / IFGC edition adopted in your jurisdiction.
Field names used by the API: device_class, flow_gpm, pipe_size_in, pressure_loss_psi
- Curve table data/plumbing/backflow-curves.json keyed to device class and sizeWatts technical bulletins