10
VALVE/TRIM INSTALLATION
1.
Make sure trim drawings match system requirements.
Refer to page 5 for the listing.
2.
Remove all plastic caps and foam spacers from valve.
3.
Apply a small amount of Teflon* tape to external
threads of all threaded pipe connections. Be careful not to
get any foreign material into the valve body, pipe nipples,
or valve openings.
4. For valves 3" (80 mm) or smaller:
4a.
Remove piston assembly before trimming valve.
4b.
Unscrew piston from valve body, and note position of
o-ring. This o-ring must be installed in the same position
when the piston is reassembled.
4c.
Install trim to back of valve, per applicable trim draw-
ings.
4d.
Reassemble piston, making sure o-ring is positioned
properly and that the piston rod and latch engage prop-
erly.
NOTE:
It may be necessary to rotate latch inward
(toward center of valve body) to ensure proper alignment.
4e.
Tighten piston until metal-to-metal contact occurs
between piston and valve body.
5.
Install valve, trim, and accessories per applicable trim
drawings.
*Teflon is a registered trademark of I. E. Dupont de Nemours
6. For valves installed with a Series 746 Dry
Accelerator:
6a.
Make sure the Series 746 Dry Accelerator is installed
on the Series 79N Electric/Pneumatic Actuator, as shown
in the drawing below. The end with the vent seal "button"
must be installed toward the actuator.
7.
Provide an uninterrupted source of water from
upstream of the main control valve to supply pressure to
the piston charge line
.
IMPORTANT SETTINGS
System and pilot supervisory switches are required for
the electric/pneumatic system. Both switches must be
set to the notes below.
1.
Wire the air supervisory switches to activate a low-
pressure alarm signal.
NOTE:
The authority having juris-
diction may also require a high-pressure alarm.
2.
Set the air supervisory switches to activate at 2 - 4 psi
(14 - 28 kPa) below the minimum air pressure required.
3.
Wire the alarm pressure switch to activate a water flow
alarm.
4.
Set the alarm pressure switch to activate on a pressure
rise of 4 – 8 psi (28 – 55 kPa).
HYDROSTATIC TESTING
The Victaulic Series 758 Preaction Valve is manufactured
and listed for a maximum working pressure of 300 psi
(2065 kPa) and is factory tested to 600 psi (4135 kPa). The
valve may be hydrostatically tested to 200 psi (1380 kPa)
and/or 50 psi (345 kPa) above the normal water supply
pressure (2-hour limited time period) for acceptance by
the authority having jurisdiction.
• Make sure the foam spacer is removed before
attempting to install the valve.
Failure to follow this instruction could cause improper
valve operation, resulting in serious personal injury and/
or property damage.
• Make sure no foreign material gets into the valve body, pipe nipples, or valve
openings.
• If using any material other than Teflon tape, use extra caution so that no material
gets into the trim.
Failure to follow these instructions could cause improper valve operation and prop-
erty damage.
• Make sure piston is reassembled and reinstalled
correctly.
Failure to do so could cause improper valve operation,
resulting in serious personal injury and/or property
damage.
• If air testing is required, DO NOT exceed 50 psi
(345 kPa) air pressure.
Failure to follow this instruction could result in serious
personal injury, property damage, and/or product
damage.
DISCONTINUED
PRODUCT
