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a company
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NOTE: Flushing of all pipe lines is to be performed to remove
all debris prior to installing valve.
NOTE: If installation is subject to very low flow or potentially
static conditions it is recommended a pressure relief valve
(1/2" minimum) be installed downstream of the pressure
reducing valve for additional system protection.
1. For making adjustments and servicing allow for adequate space
around the valve before installing valve.
2. When installing a ZW209 or ZW209BP, gate valves installed on
both inlet and outlet are recommended for maintenance allowing
for isolation of valve.
3. Position the valve in line matching the direction of flow as
indicated on the valve model tag with the proper direction of flow
in the system. Once attached to line, double check all fasteners/
bolts in the pilot system and on main valve are tight and there is
no damage prior to pressurizing system.
NOTE: Pressure in some applications can be very high so be
thorough in checking and inspecting for proper installation
and makeup.
4. Zurn Wilkins valves are designed to operate in both the vertical
and horizontal positions. However, it is recommended that ZW209
6” and larger, be installation in the horizontal position. The hori-
zontal positioning of the larger valves avoids premature wear due
to the mass of plunger assemblies as well as allows for greater
accessibility during annual inspections, and maintenance.
ZW209 SCHEMATIC
STANDARD COMPONENTS
1 Main Valve
2 850MXL Isolation Valve
3 SXL Wye Type Strainer
4 Pressure Gauge
5 Restriction Tube Fitting
6 NR3XLHRSC PRV (15-150 psi)
Installation
Troubleshooting
Maintenance Instructions
Model ZW209 & ZW209BP
Pressure Reducing Valve Assembly & with Low Flow By-Pass
2", 2-1/2", 3", 4", 6" & 8"
OPTIONAL FEATURES
C 40XL Hydraulic Check w/
Isolation Valve
L SC1 Closing Speed Control
O SC1 Opening Speed Control
Z ZPI Valve Position Indicator
6 PV-PRD (20-200 psi)
the valve assembly it is also recommended that a ZPI valve
position indicator be installed to aid in verifying proper valve
movement.
3. As the valve is filling with water, it is necessary to bleed the
main valve and pilot system of air. To vent air, partially open or
loosen the highest plugs or fittings in the system. The ZPI valve
position indicator is a great location, as it has a test cock at the
top to vent air pressure. It may be necessary to bleed system
more than once. After removal of air in the system tighten all
loose fittings.
4. Before setting valve, if valve is equipped with SC1 Flow con-
trols (O or L on ZW209 schematic) it is necessary to back out
the set screw a minimum of 3 turns from initial set point.
5. At this point with the upstream shutoff valve partially open,
slowly open the downstream shut off valve. Flow will begin to
occur and pressure should build up in valve and eventually
stabilize.
6. Next it is advisable to flow water through the valve to ensure all
air has been escaped from system. With water flowing through
the valve the Zurn Wilkins PRV pilot can be set to the desired
pressure. To adjust the pilot, loosen jam nut on adjustment screw
and either turn adjustment screw in (to increase pressure) or
out (to decrease pressure). Tighten jam nut on pilot when the
desired setting has been made. For ZW209BP the low flow by-
pass control must be set 5 psi greater than main Pilot PRV.
7. To verify proper operation of ZW209 & ZW209BP close and
open downstream shut off valve several times to ensure down-
stream pressure is stable at set pressure. To verify by-pass op-
eration, close isolation valves on main pilot slowly. Then check
the downstream pressure. It should be regulating 5 psi higher
than normal Pilot PRV.
8. After pilot system has been adjusted and the valve is properly
regulating the main valve opening and closing speed controls
(O or L) can be adjusted as needed.
9. When setting speed controls, turning the adjustment screw
into the speed control will restrict the amount of flow through the
needle valve. Depending on whether the control is for opening
or closing (refer to ZW209 schematic) the control will either slow
the opening or closing of the main valve when the adjustment
screw is turned into the speed control. Adjust as needed and
tighten jam nut. In general a closing speed control on a ZW209
and ZW209BP should be at least 3 turns in from the furthest
open position to prevent high pressure surges downstream.
START-UP
CAUTION:
To prevent personnel injury and damage to equip-
ment check that downstream venting is adequate prior to
start-up and test procedures.
All adjustments under pressure
should be made slowly while under flowing conditions.
If
the main valve closes too fast it may cause surging in upstream
piping.
1. Open isolation valves (2) in the pilot system (see ZW209 or
ZW209BP schematic).
2. Then slowly open the upstream shutoff valve only enough to
fill main valve assembly and pilot system. Prior to pressurizing
WILKINS, a ZURN company
1747 Commerce Way, Paso Robles, CA 93446 Phone:805-238-7100 Fax:805-238-5766
a company
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Troubleshooting
The following troubleshooting information in Tables 1 & 2 deals
strictly with the ZW209 and ZW209BP valve and pilot systems.
It is recommended to verify that the pilot system is properly
functioning before troubleshooting the main valve. All trouble-
shooting can be performed without removing the cover. It is also
recommended to permanently install a model ZPI valve position
indicator and an additional gauge in one of the cover connec-
tions.
Installation / Start-up
