Zurn Wilkins P4000A Installation, Start-Up, Maintenance Instructions

Model P4000A & P4000AHR
Thermal Expansion Relief Valve
1/2" & 3/4"
Installation

DESCRIPTION
The Zurn Wilkins P4000A Thermal Expansion Relief Valve is
a direct acting relief valve. The P4000A uses a spring to force
the plunger down upon a seat causing the valve to be normally
closed. The P4000A can be set to relieve pressures from 50
to 200 psi and the P4000AHR from 150 to 300 psi. When the
inlet pressure reaches the set pressure point it pushes up on
the diaphragm which pulls the plunger off the seat. The valve
opens to relieve pressure at the inlet and allows water to flow
downstream. The P4000A opens and closes within a close
pressure range of the set pressure.
All the instructions and references apply to both models, P4000A
& P4000AHR.
Installation / Start-up
INSTALLATION
NOTE: Prior to installation of the P4000A, ensure all debris
is flushed out the piping system.
1. During the installation of a P4000A in a sprinkler system, Under-
writer Laboratories (UL) requires NFPA 13 "Standard for Installation
of Sprinkler Systems" be followed.
2. Upon installation UL also requires that the P4000A be tested in
accordance with NFPA 13. Thereafter the valve shall be inspected,
tested, and maintained in accordance to NFPA 25 "Standard for
the Inspection, Testing, and Maintenance of Water-Based Fire
Protection Systems".
3. For making adjustments and servicing allow for adequate
space around the valve.
4. Position the P4000A 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
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.
WARNING: Supply adequate drainage on the discharge of
the P4000A. To avoid water damage, valve must be plumbed
to a safe drain.
5. Zurn Wilkins valves are designed to operate in both the verti-
cal and horizontal positions.
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.
NOTICE: Annual inspection and maintenance is required of all plumbing system components. To ensure proper perfor-
mance and maximum life, this product must be subject to regular inspection, testing and cleaning.
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Start-up
 
1.
is compressed fully.
Caution: Do not over tighten the adjustment screw to pre-
vent damaging the valve.
2.
adjustment screw counterclockwise until the first sign of water
flow. Either listen carefully to the valve for water flow or look
through a downstream sight glass.
3.
pressure at the first sign of water flow through the relief valve. If
the desired set pressure is different than current inlet pressure
use the table below. Turn the adjustment screw clockwise to
increase set pressure or counterclockwise to decrease set pres-
sure. Add or subtract from the current inlet pressure by turning
the adjustment screw the number of turns required to reach the
desired set pressure based on the adjustment table.
Note: The valve must be set 10 psi greater than the maxi-
mum anticipated system pressure.
*Note: Pressure change per turn is approximate. Use a
gauge at the inlet of P4000A to set /check relief pressure.
4. To verify proper operation of the P4000A, view the valve
during normal operation and check the valve for relief setting.
Adjustments can be made at anytime.
1747 Commerce Way, Paso Robles, CA 93446 Phone:855-663-9876 Fax:805-238-5766
Maintenance Instructions
P4000A
Turn the adjustment screw clockwise until the valve spring
With the inlet of the P4000A pressurized slowly turn the
The valve is set to relieve pressure at the current inlet
Relief Pilot Pressure Change per
Adjustment Range
50 - 200
150 - 300
FM
APPROVED
P4000AHR
Turn (PSI)*
23
28.5
ZURN WILKINS
www.zurn.com
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