RPZ Backflow Assembly
You're on site at a pressurized RPZ assembly. Test it with the kit following the procedure, decide what (if anything) has failed, then check your answer.
Supply
Downstream
Valves
You can also click the shutoff and test cock handles on the drawing.
Faults
Using the test kit
Needle valves. Each valve's knob sits just right of its hose on the bottom of the kit. Drag the knob up to open, down to close, or scroll over it. A single click snaps it fully open or fully shut.
Hoses. Click a hose's nut at the kit to loosen it (water and air spill out at the joint, which is how you bleed a hose) and click again to tighten. Drag the nut off the fitting to disconnect it, or back on to connect. Drag a hose's other end onto a test cock.
Test kit
- High side
- Low side
- Vent side
Air in the kit makes the reading wander and bubbles out wherever water carries it to atmosphere: bleed the low side with B + vent, the high side with A + vent, and a hose by loosening its nut at the kit.
Springs
Readings
- Supply (TC #1)
- Inlet (TC #2)
- Zone (TC #3)
- Outlet (TC #4)
- System
- Check #1
- Check #2
- Relief valve