municipal supply pressure at the design flow rate, less piping friction loss and elevation
loss.
2. Turn to the appropriate valve performance chart. The valve model and flow range for
each graph is indicated in the title at the top of the graph. Be sure to use the correct
graph for the designed flow rate through the valve.
3. Locate the valve inlet residual pressure on the vertical axis of the chart and draw a line
from the pressure horizontally across the chart.
4. Locate the desired valve outlet residual pressure on the chart horizontal axis and draw a
vertical line from this pressure across the chart
5. From the intersection of the inlet and outlet pressure lines constructed in (3) and (4)
above, move horizontally to the nearest valve performance curve (actually straight
diagonal lines). This will be the appropriate valve setting for the chosen location.
6. Determine the valve static inlet pressure. This will be the sum of the municipal supply
static pressure plus the pump churn pressure, less the elevation loss.
7. To determine the valve static outlet pressure, refer to the appropriate static chart.
Locate the valve static inlet pressure on the vertical axis of the chart. Follow across to
the appropriate valve curve and drop down to the horizontal axis to read valve outlet
static pressure.
8. If static outlet pressure is found to exceed the maximum outlet pressure allowed by
NFPA 13 or NPFA 14, it will be necessary to re-select a valve setting to the left of the
originally chosen type.
SETTING PRESSURE REDUCTION
1. Remove the tamper-resistant screw from the clear cover by means of tamper-resistant Allen
wrench provided with valve.
2. Insert adjustment tool provided with valve through the slot in the clear cover into the hole
in the adjustment cylinder.
3. Rotate adjustment cylinder until the top of the adjustment cylinder is aligned with desired
mark on the Indication Label (refer to Figure 1).
4. Once rotation limit is reached during adjustment remove the adjustment tool from the
adjustment cylinder hole and re-insert the adjustment tool into the next available hole.
ADJUSTMENT CYLINDER
TOP
SETTING “A”
SETTING “E”
Figure - 1
