Victaulic FireLock 758-LPA Series User manual

Series 758-LPA
FireLock
™
Preaction Valve
with Series 776
Low-Pressure Actuator
Double-Interlock, Pneumatic/Electric
Release Trim
Hang these instructions on the
installed valve for easy future reference.
Failure to follow instructions and warnings can result in serious personal injury, property damage, and/or product failure.
• Read and understand all installation instructions before attempting to install any Victaulic piping products.
•Wear safety glasses, hardhat, and foot protection.
If you need additional copies of any literature, or if you have any questions about the safe installation and operation of this product,
contact Victaulic Company, P.O. Box 31, Easton, PA 18044-0031, USA, Telephone: 1-800-PICK VIC, e-mail: [email protected].
Installation, Maintenance, & Testing Manual
R
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1
TABLE OF CONTENTS
HAZARD IDENTIFICATION
Definitions for identifying the various hazard levels are provided below.
This safety alert symbol indicates important safety messages. When you see this symbol, be alert to the
possibility of personal injury. Carefully read and fully understand the message that follows.
NOTICE
The use of the word “NOTICE” identifies special instructions that are
important but not related to hazards.
The use of the word “CAUTION” identifies possible hazards or unsafe prac-
tices that could result in personal injury and product or property damage if
instructions, including recommended precautions, are not followed.
The use of the word “WARNING” identifies the presence of hazards or un-
safe practices that could result in death or serious personal injury if in-
structions, including recommended precautions, are not followed.
® Registered Trademark of Victaulic © Copyright 2002 Victaulic Printed in U.S.A
Hazard Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Installer Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . .2
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Trim Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Exploded View Drawing - Trim Components. . . . . . . . . . .4
Exploded View Drawing - Internal Valve Components. . .5
Series 758 Preaction Valve with Series 776 Low-Pressure
Actuator – Trim Assembly Drawing Numbers . . . . . . . .5
Section View Drawing and Description – Series 776
Low-Pressure Actuator Operation . . . . . . . . . . . . . . . . . .6
Section View Drawing and Description – Series 746
Dry Accelerator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Compressor and Air Maintenance Trim Requirements . .8
Air Supply Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Proper Air Supplies for Series 758 Preaction
Valves Used with Series 776 Low-Pressure
Actuators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Proper Air Supplies for Series 758 Preaction
Valves Used with Series 776 Low-Pressure
Actuators and Series 746 Dry Accelerators . . . . . . . . . .9
Important Installation Information. . . . . . . . . . . . . . . . . . . .9
Valve/Trim Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Important Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Hydrostatic Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Placing the System in Service. . . . . . . . . . . . . . . . . . . . . .11
External Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Weekly Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Monthly Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Required Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Main Drain Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Water Flow Alarm Test . . . . . . . . . . . . . . . . . . . . . . . . . 18
Water Level and Low-Air Alarm Tests . . . . . . . . . . . . 20
Trip Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Partial Trip Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Full Trip Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Required Internal Inspection . . . . . . . . . . . . . . . . . . . . . . 26
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Removing and Replacing Clapper Seal. . . . . . . . . . . . 28
Removing and Replacing Clapper Assembly . . . . . . . 30
Installing Cover Plate Gasket and Cover Plate . . . . . . 31
Removing and Replacing Piston Assembly . . . . . . . . 32
Replacing the Strainer Screen for Series 776
Low-Pressure Actuators. . . . . . . . . . . . . . . . . . . . . . . . 33
Troubleshooting – Series 776 Low Pressure
Actuator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Troubleshooting – Series 746 Dry Accelerator . . . . . . . . 34
Troubleshooting – System . . . . . . . . . . . . . . . . . . . . . . . . 34
Warranty. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B/C
Facilities Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B/C
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INSTALLER SAFETY INSTRUCTIONS
GENERAL
1. Read and understand all instructions before proceeding with the installation, maintenance, and testing of this
Victaulic fire protection device.
2.
Use only recommended accessories. Use of improper accessories or equipment could result in improper system operation.
3.
Avoid dangerous environments. If using electrically powered tools for installation, make sure the area is moisture-free. Keep
work areas well lit. Allow enough space for installing the device, trim, and accessories safely and efficiently.
4.
Prevent back injury. Larger and pre-trimmed valves are heavier and may require more than one person or mechanical lifting
equipment to position and install the assembly properly. Always practice proper lifting techniques.
5.
Inspect the shipment. Make sure all components are included with the shipment and that all necessary tools are available for
proper installation.
6.
Wear safety glasses, hardhat, foot protection, and hearing protection. Protect your hearing if you are exposed to long
periods of very noisy job-site operations.
7.
Watch for pinch points. Do not put fingers under the valve body where they could be pinched by the weight of the valve. Use
caution around spring-loaded components, such as the clapper, the clapper latch, and the piston assembly.
8.
Keep work areas clean. Cluttered areas, benches, and slippery floors can create hazardous working conditions.
9.
Keep visitors away. Keep all visitors a safe distance away from work areas.
MAINTENANCE AND TESTING
1.
Notify the authority having jurisdiction. Always notify the authority having jurisdiction before taking a fire protection
system out of service, or before performing any maintenance that eliminates the fire protection provided by the system.
2.
Depressurize and drain the system completely before performing any maintenance. Water under pressure, trapped
air, or system air pressure may be present and can create hazardous conditions.
3.
Follow NFPA requirements for testing and inspection schedules. Contact the local authority having jurisdiction for any
additional requirements.
4.
Keep the preaction system away from corrosive atmospheres and foreign matter. Any condition that might degrade
the system or affect system performance must be avoided.
•Anexperienced,trainedinstallermustinstallthisproductinaccordancewithallinstructions.Theseinstructions
contain important information.
Failure to follow these instructions could result in serious personal injury, property damage, and/or product
failure.
Ifyouneedadditionalcopiesof any literature,orif you haveanyquestions about thesafeinstallation and operation
of this valve, contact Victaulic Company, P.O. Box 31, Easton, PA 18044-0031 USA, Telephone: 1-800-PICK Vic,
e-mail: [email protected].
• Depressurize and drain piping systems before attempting to install or remove any Victaulic piping products.
Failure to follow this instruction could result in serious personal injury, property damage, and/or product
damage.
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INTRODUCTION
The following instructions are a guide for proper installation of Victaulic Series 758 Preaction Valves. These instructions
involve pipe that is properly prepared and grooved in accordance with current Victaulic specifications.
TRIM DIMENSIONS
NOTE: The drawings below show a 4-inch (100-mm) configuration.
VALVE SIZE Dimensions
inches/mm
Aprx. Weight Each
lbs./kg
Nominal
Dia.
in/mm
Actual
Out. Dia.
in/mm
Without Trim With Trim
ABCDEFGH IFlanged Grooved Flanged Grooved
GROOVED
✕ GROOVED
1 ¹⁄₂ 1.900 9.00 23.50 13.00 18.00 13.00 10.00 7.00 4.00 4.00 – 16.7 – 43.0
40 48,3 228,60 597 330 457 330 254 178 102 102 – 7,6 – 19,5
2 2.375 9.00 23.50 13.00 18.00 13.00 10.00 7.00 4.00 4.00 – 17.0 – 43.0
50 60,3 228,60 597 330 457 330 254 178 102 102 – 7,7 – 19,5
2 ¹⁄₂ 2.875 12.61 25.50 14.00 20.00 15.50 11.50 7.50 5.00 5.00 – 41.2 – 65.0
65 73,0 320,29 648 356 508 393 292 191 127 127 – 18,7 – 29,5
76,1 mm 3.000 12.61 25.50 14.00 20.00 15.50 11.50 7.50 5.00 5.00 – 41.2 – 65.0
76,1 320,29 648 356 508 394 292 191 127 127 – 18,7 – 29,5
3 3.500 12.61 25.50 14.00 20.00 15.50 11.50 7.50 5.00 5.00 – 42.1 – 65.0
80 88,9 320,29 648 356 508 394 292 191 127 127 – 19,1 – 29,5
4 4.500 15.03 23.00 15.00 21.00 14.00 12.00 8.00 9.00 6.00 – 55.0 – 95.0
100 114,3 381,76 584 381 533 356 305 203 229 152 – 24,9 – 43,1
6 6.625 16.00 22.00 16.00 22.00 14.00 12.00 8.50 7.00 7.00 – 73.0 – 115.0
150 168,3 406,40 559 406 559 356 305 216 178 178 – 33,1 – 52,2
165,1 mm 6.500 16.00 22.00 16.00 22.00 14.00 12.00 8.50 7.00 7.00 – 73.0 – 115.0
165,1 406,40 559 406 559 356 305 216 178 178 – 33,1 – 52,2
8 8.625 17.50 22.00 16.00 23.00 16.00 12.00 14.00 9.50 7.00 – 142.0 – 182.0
200 219,1 444,50 559 406 584 406 305 356 241 178 – 64,4 – 82,6
GROOVED ✕ FLANGED
4 4.500 15.64 23.00 15.00 21.00 14.00 12.00 8.00 9.00 6.00 65.0 – 105.0 –
100 114,3 397,26 584 356 533 356 305 203 229 152 29,5 – 47,6 –
6 6.625 16.94 22.00 16.00 22.00 14.00 12.00 8.50 7.00 7.00 83.0 – 125.0 –
150 168,3 430,28 559 406 559 356 305 216 178 178 37,6 – 56,7 –
165,1 mm 6.500 16.94 22.00 16.00 22.00 14.00 12.00 8.50 7.00 7.00 83.0 – 125.0 –
165,1 430,28 559 406 559 356 305 216 178 178 37,6 – 56,7 –
8 8.625 19.27 22.00 16.00 23.00 16.00 12.00 14.00 9.50 7.00 155.0 – 195.0 –
200 219,1 489,46 559 406 584 406 305 356 241 178 70,3 – 88,5 –
DB
A
H
E F C
G
I
NOTE: An optional Series 746 Dry Accel-
eratorassemblyaddsapproximately13.5"
(342,9 mm) onto the top of the Series
776 Low-Pressure Actuator.
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To
Drain
To DrainTo
Drain
To
Drain
To
Drain
To
Drain
Optional Air
Maintenance
Device
To Drip Cup
Water
Supply
33
BILL OF MATERIALS
1 Series 758 FireLock Actuated Check Valve 17 Water Supply Pressure Gauge (0-300 psi/0-2068 kPa)
with Double-Interlock (pneu/elec) trim 18 Series 749 AutoDrain
2 Piston Charge Line Ball Valve (NO) 19 Series 748 Ball Check Valve
3 Piston Charge Line Strainer (100 Mesh) 20 System Pressure Gauge (0-80 psi/0-552 kPa with retard)
4 Piston Charge Line Swing Check Valve 21 Air Line Strainer (100 Mesh)
5 Piston Charge Line Restrictor (¹⁄₁₆") 22 Air Line Restrictor (¹⁄₁₆")
6 Piston Charge Line Pressure Gauge (0-300 psi/0-2068 kPa) 23 Series 776 Low Pressure Actuator
7 Gauge Valve 24 Pressure Gauge (0-80 psi/0-552 kPa with retard)
8 Alarm Line Ball Valve (NO) 25 Pressure Bleed Ball Valve
9 Series 729 Drip Check Valve 26 Series 753E Electric Solenoid Valve
10 Alarm Test Line Ball Valve (NC) 27 Series 755 Manual Pull Station
11 Alarm Line Drain Restrictor (¹⁄₁₆") 28 Series 757 Air Maintenance Device (Optional)
12 Alarm Line Drain Ball Valve (NC) 29 EPS-10 Alarm Pressure Switch (Optional)
13 Main System Drain Valve 30 EPS-40 Supervisory Switch (Optional)
14 Main Drain Valve - Flow Test 31 Series 760 Water Motor Alarm (Optional)
15 Drip Cup 32 Series 705W Butterfly Valve (Optional)
16 Drain Swing Check Valve 33 Style 005 FireLock Rigid Coupling (Optional)
WATER MOTOR
ALARM
SERIES 760
UL
C
FM
LISTED
31
12
32
15
29
1
14
8
16
22
9
24
13
10
11
28
20
19
23
21
4
5
7
27
30
26
6
23
17
18
25
7
NO = Normally Open; NC = Normally Closed
EXPLODED VIEW DRAWING – TRIM COMPONENTS
Series 758 Actuated Valve
With Double-Interlock, Pneumatic/Electric Release - Preaction Trim
(Optional Accessories Also Shown)
Flanged ✕Grooved
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EXPLODED VIEW DRAWING – INTERNAL VALVE COMPONENTS
SERIES 758 PREACTION VALVE WITH SERIES 776 LOW-PRESSURE
ACTUATOR – TRIM ASSEMBLY DRAWING NUMBERS
VALVE SIZE Vertical Trim
Drawing
Number
Horizontal Trim
Drawing
Number
VALVE SIZE Vertical Trim
Drawing
Number
Horizontal Trim
Drawing
Number
Nominal
Outside Dia.
in/mm
Actual
Outside Dia.
in/mm
Nominal
Out. Dia.
in/mm
Actual
Out.Dia.
in/mm
1 ¹⁄₂ 1.900
Z014758829 Z014758879
4 4.500
Z040758829 Z040758879
40 48,3 100 114,3
2 2.375
Z014758829 Z014758879
6 6.625
Z060758829 Z060758879
50 60,3 150 168,3
2 ¹⁄₂ 2.875
Z024758829 Z024758879
165,1 mm 6.500
Z060758829 Z060758879
65 73,0 165,1
76,1 mm 3.000
Z024758829 Z024758879
8 8.625
Z080758829 Z080758879
76,1 200 219,1
3 3.500
Z024758829 Z024758879
80 88,9
1
17
16
12
11
21
20
9
4
19
3
10
18
7
6
5
814
13
2
15
BILL OF MATERIALS
1 Valve Body 8 Bolt Seal 15 Cover Plate Bolts (Qty.7)
2 Clapper 9 Clapper Spring 16 Piston
3 Clapper Seal 10 Spacers (Qty. 2) 17 Piston O-ring
4 Seal Ring 11 Clapper Shaft 18 Latch
5 Seal Washer 12 Clapper Shaft Retaining Plug (Qty. 2) 19 Latch Spring
6 Seal Retaining Ring 13 Cover Plate 20 Latch Shaft
7 Seal Assembly Bolt 14 Cover Plate Gasket 21 Latch Shaft Retaining Plug (Qty. 2)
Clapper
Latch
Piston
Assembly
Alarm
Outlet
Alarm
Test Seat
Seal
"WEEP" Hole
(Deluge and Preaction Valves)
Exaggerated for Clarity
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SECTION VIEW DRAWING AND DESCRIPTION –
SERIES 776 LOW-PRESSURE ACTUATOR OPERATION
The Series 776 Low-Pressure Actuator is located in the
trim of pneumatically released Series 758 Preaction Valves
and acts as the trigger for these systems.
Diaphragms separate the low-pressure actuator into three
chambers. The upper air chamber controls activation,
while the middle and lower chambers act as the water
valve.
During setup, system air is applied to the upper chamber
of the low-pressure actuator. When the auto vent knob of
the low-pressure actuator is pulled up, the upper chamber
manually sets. Air pressure in the upper chamber holds
the auto vent closed, while it exerts force on the water
seal of the middle chamber.
When the piston charge line is opened, water enters the
lower chamber of the low-pressure actuator. Water enter-
ing the low-pressure actuator flows to the middle cham-
ber through the inlet eyelet, which is pressurized by
system air pressure in the upper chamber.
Since the area of the lower diaphragm (exposed to water
pressure in the middle chamber) is greater than the area
of the lower chamber, the lower chamber seals off. No
water flows to the low-pressure actuator’s outlet, and the
supply water pressure creates the water seal.
When system air pressure decays to 6.5 psi (45 kPa), the
force exerted by the compression spring in the auto vent
is greater than the force exerted by air in the upper cham-
ber. The auto vent opens, and all air pressure in the upper
chamber evacuates.
The upper diaphragm releases water pressure in the mid-
dle chamber of the low-pressure actuator, which allows
the lower diaphragm to lift and water to flow from the
inlet to the outlet. This water flow releases water pressure
from the piston charge line of the preaction valve, thus
allowing the piston to retract. The preaction valve’s clap-
per opens, and water flows into the sprinkler system.
VENT TO ATMOSPHERE
WATER IN
AIR IN
TO DRAIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
BILL OF MATERIALS
Item Description Item Description
1 Protective Cap 9 Lower Diaphragm Assembly
2 Auto Vent Knob 10 Strainer Screen
3 Auto Vent Assembly 11 Strainer O-Ring Seal
4 Upper Chamber 12 Strainer Assembly
5 Upper Diaphragm Wave Spring 13 Inlet Eyelet
6 Lower Diaphragm Wave Spring 14 Middle Chamber
7 Outlet Eyelet 15 Upper Diaphragm Assembly
8 Lower Chamber
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SECTION VIEW DRAWING AND DESCRIPTION –
SERIES 746 DRY ACCELERATOR
The Series 746 Dry Accelerator exhausts air from the actuator to speed the operation of the valve.
A diaphragm separates the Series 746 Dry Accelerator into two chambers. The closing chamber contains a compression
spring, which maintains this chamber in the closed position. This closed position is maintained as long as the pressure
differential between the opening and closing chambers is less than 3 psi (21 kPa).
When the system introduces air pressure into the dry accelerator, the air goes into the closing chamber and passes
through a built-in check valve to the opening chamber. The built-in check valve, which allows flow into the opening
chamber, prevents pressure from escaping the opening chamber. Therefore, air can escape only through the restrictor.
When a rapid loss of system air pressure occurs, such as an open sprinkler, air escapes from the closing chamber faster
than it does from the opening chamber. As the sprinkler system’s pressure continues to decay, a differential pressure
develops across the diaphragm. When this differential pressure reaches 3 – 5 psi (21 – 34 kPa), the opening chamber’s
pressure overcomes the compression spring’s closing force, causing the closing chamber to open to the atmosphere.
The closing chamber opens immediately and releases pressure from the actuator, resulting in valve operation.
To Pressure
Gauge
Air Inlet from
Actuator
14
11
12
13 10
9
8
7
4
6
5
3
1
215
Exaggerated for Clarity
BILL OF MATERIALS
Item Description Item Description
1 Opening Chamber 9 o-ring
2 Restrictor 10 Seal Support
3 Piston 11 Closing Chamber Seal
4 o-ring 12 Button Head Cap Screw
5 Diaphragm 13 Washer
6 Actuator Shaft 14 Adjustable Seat
7 Closing Chamber 15 Built-In Check Valve
8 Compression Spring
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RECOMMENDED AIR PRESSURES FOR SERIES
758 PREACTION VALVES WITH SERIES 776
LOW-PRESSURE ACTUATORS
NOTES:
1) The recommended air pressures, shown in the chart above, apply
to preaction valves that use a Series 776 Low-Pressure Actuator at
13-psi (90-kPa) minimum and 18-psi (124-kPa) maximum. If the air
pressure is higher than 18-psi (124-kPa), a Series 746 Dry Accelera-
tor should be installed.
2) For base or riser-mounted compressors, the recommended air
pressures are the "on" or "low" pressure settings for the compressor.
3) For tank-mounted compressors, the recommended air pressures
are the set point for the air regulator. The “on” pressure of the com-
pressor should be at least 5 psi (34 kPa) above the set point of the
regulator.
4) The Victaulic air regulator is a relief-type design. Any pressure in
the system that is above the set point of the regulator will be
released. Therefore, charging the regulator above the set point
could cause premature operation of a valve installed with a Series
746 Dry Accelerator.
Air Maintenance Trim Assembly
(AMTA)
COMPRESSOR AND AIR
MAINTENANCE TRIM
REQUIREMENTS
COMPRESSOR REQUIREMENTS
Air Supply Design
1. The engineer/system designer is responsible for sizing
the compressor so that it brings the entire system to the
required pressure within 30 minutes. DO NOT oversize
the compressor to provide more airflow, since it will slow
down or possibly prevent valve operation.
2. Continuous service (24 hours per day, 7 days per week)
is required to prevent the valve from false tripping due to
a loss of air pressure.
3. Regulate the air pressure to the proper system air pres-
sure. Air pressure differing from the required system air
pressure could adversely affect system operation.
4. Restrict the air supply to ensure that air being
exhausted from an open sprinkler or manual release valve
is not replaced by the air supply system as fast as it is
being exhausted.
5. The inspector’s test connection should contain a globe
valve (normally closed), which can be opened to simulate
the actuation of a sprinkler.
BILL OF MATERIALS
Item Description
1 ¹⁄₈ -inch (3,2-mm) Restrictor
2 Slow-Fill Ball Valve (Normally Open)
3 Air Regulator
4 Strainer (100 Mesh)
5 Spring-Loaded, Soft-Seated Ball Check Valve
6 Fast-Fill Ball Valve (Normally Closed)
AIR PRESSURE – PSI
MAXIMUM WATER SUPPLY PRESSURE - PSI (Peak)
30
25
20
15
10
5
05 10 15 20 25 50 75 100 125 150 175 200 225 250 275 300
16
54
2
3
NOTICE
•In the event that a compressor becomes inoperative, a properly sized tank-
mounted air compressor provides the greatest protection for systems that use a
Series 746 Dry Accelerator. In this situation, air can be supplied continuously to
the sprinkler system for an extended time period.
• If multiple preaction valves are installed with a common air supply, isolate the
systems by using a spring-loaded, soft seat-check valve to ensure air integrity for
each system.
•Good practice is to include a control valve for isolation and service of each
individual system.
• Air supply systems must be properly sized.
Failure to follow this instruction could cause
improper valve operation, resulting in serious
personal injury and/or property damage.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
50
System Capacity (in gallons)
Required Flow Rate (CFM)
COMPRESSOR REQUIREMENTS
150 250 350 450 550 650 750 850 950 1050 1150 1250 1350 1450 1550 1650 1750
55 psi (379 kPa)
40 psi (276 kPa)
20 psi (138 kPa)
13 psi (90 kPa)
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9
5a. Locate the inspector’s test connection at the most
hydraulically demanding location in the release system.
NOTE: Multiple restrictions on the inspector’s test may
slow the air decay rate, causing the system to respond
slower than required.
5b. The inspector’s test connection should terminate
with an orifice equal to the smallest orifice in the releasing
system.
5c. The inspector’s test connection is used to ensure that
water gets to the most remote part of the system within
60 seconds.
6. When shop air or a tank-mounted air compressor is
installed, the air maintenance trim assembly MUST be
used. The air maintenance trim assembly provides proper
air regulation to the sprinkler system.
6a. Set the air regulator to 13 psi (90 kPa).
Proper Air Supplies for Series 758
Preaction Valves Used with Series
776 Low-Pressure Actuators:
1. A preaction valve, installed with a Series 776 Low-Pres-
sure Actuator, MUST contain an air regulator.
2. When a riser or base-mounted air compressor supplies
air to a system using a Series 776 Low-Pressure Actuator,
it is not necessary to use the air maintenance trim assem-
bly with the air regulator. In this case, the airline of the
compressor connects to the trim at the fitting where the
air maintenance trim is normally installed (refer to the
trim drawing). NOTE: The use of an air regulator with a
base or riser-mounted compressor could cause short
cycling, resulting in premature wear of the compressor.
3. Due to the large on/off differential available for pressure
switches that control base-mounted compressors, adjust
the compressor‘s pressure switch so that the "ON" con-
tact is set at 13 psi (90 kPa).
Proper Air Supplies for Series 758
Preaction Valves Used with Series
776 Low-Pressure Actuators and
Series 746 Dry Accelerators:
1. When a Series 746 Dry Accelerator is used with the
Series 776 Low-Pressure Actuator, the air maintenance
trim assembly MUST be used with the air regulator.
2. In the event that a compressor becomes inoperative, a
properly sized tank-mounted air compressor provides the
greatest protection for systems that use a Series 746 Dry
Accelerator. In this situation, air can be supplied continu-
ously to the sprinkler system for an extended time period.
IMPORTANT INSTALLATION
INFORMATION
1. For proper operation and approval, the Series 758 Pre-
action Valve must be installed in accordance with the
specific trim diagrams. NOTE: Victaulic provides specific
trim drawings for installations that involve a Series 746
Dry Accelerator.
2. Before installing the Series 758 Preaction Valve, flush
the water supply piping thoroughly to ensure that no for-
eign material is present.
3. The Series 758 Preaction Valve MUST NOT be located
in an area where the valve is subject to freezing tempera-
tures or physical damage.
4. It is the owner’s responsibility to confirm material com-
patibility of the Series 758 Preaction Valve, trim, and asso-
ciated accessories when a corrosive environment or
contaminated water is present.
5. Series 758 Preaction Valves can be installed in the ver-
tical position with the arrow on the body pointing upward
or horizontally with the cover plate facing upward.
6. Air or nitrogen supply to the dry piping system must be
clean, dry, and oil-free.
7. Air supplies must be regulated, restricted, and continu-
ous. NOTE: Victaulic recommends the use of an air main-
tenance device on any system with an automatic air
supply.
8. When the Series 758 Preaction Valve is used with a
water motor alarm, it is recommended that the valve con-
tain an uninterrupted, low-pressure alarm that is installed
on the piston charge line downstream of the check valve.
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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 pipe joint compound or Teflon*
tape to external threads of all threaded pipe connections.
Be careful not to get any tape, compound, or other foreign
material into 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 776 Low-Pressure 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 pneumatic/electric 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/or
property 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.
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PLACING THE SYSTEM
IN SERVICE
1. Open the system main drain valve. Confirm that the
system is drained.
2. Close the system main drain valve.
3. Confirm that system drains are shut and the system is
free of leaks.
4. If a Series 746 Dry Accelerator is used, confirm that the
isolation ball valve to the accelerator is closed.
5. ACTIVATE THE ELECTRICAL PORTION OF THE
SYSTEM TO ENERGIZE THE SOLENOID. NOTE:
The solenoid must remain open until instructed other-
wise.
6. Open the piston charge line ball valve.
SERIES 749 AUTO DRAIN ASSEMBLY
•Make sure the Series 758 Preaction Valve is properly heated and protected from
freezing temperatures and physical damage.
Failure to follow this instruction could cause improper valve operation, resulting in
serious personal injury and/or property damage.
System Main
Drain Valve
System Main
Drain Valve
Accelerator
Isolation
Ball Valve
Piston
Charge Line
Ball Valve
Cap
Knob
Seal
Compression
Fitting
Drain
Hose
Body
Spring
Stem
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7. Remove the protective cap from the Series 749 Auto
Drain.
7a. Pull up on the auto drain knob, and confirm that water
is flowing through the Series 776.
7b. Replace the protective cap over the auto drain knob.
8. Close the piston charge line ball valve.
9. Charge the system with air by turning on the compres-
sor or by opening the fast-fill ball valve on the air mainte-
nance device (fast-fill ball valve is shown above). You will
need to charge the system to between 13-psi (90-kPa)
minimum and 18-psi (124-kPa) maximum.
9a. Confirm that the system is charging by observing the
air pressure gauge. If the gauge is not showing an
increase in air pressure, there is a leak or an opening in
the line.
9b. If air is leaking our of the drip check on the alarm line,
close the alarm line ball valve.
Auto Drain
Protective
Cap
Auto Drain
Knob
Auto Drain
Protective
Cap
Piston
Charge Line
Ball Valve
Fast-Fill
Ball Valve
Alarm Line
Ball Valve
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9c. While the system is charging, remove the protective
cap from the auto vent of the Series 776 Low-Pressure
Actuator.
9d. When the system reaches approximately 8 psi (55
kPa), pull up on the auto vent knob of the Series 776.
NOTE: The auto vent should seal and remain in the "UP"
position.
9e. Replace the protective cap over the auto vent knob.
9f. When the system reaches a minimum of 13 psi
(90 kPa), close the fast-fill ball valve on the air mainte-
nance device.
10. Open the slow-fill ball valve on the air maintenance
device.
11. Open the piston charge line ball valve.
•Make sure the protective cap is replaced on the Series 776 auto vent knob to avoid
accidental contact.
Hitting the knob will cause the valve to trip, resulting in property damage.
776
Protective
Cap
776
Auto Vent
Knob
776
Protective
Cap
Fast-Fill
Ball Valve
Slow-Fill
Ball Valve
Piston
Charge Line
Ball Valve
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12. Open the ¹⁄₄-inch ball valve located between the
Series 776 and the solenoid so that a stream of water
flows from the ball valve.
12a. After a stream of water is established, close the ¹⁄₄-
inch ball valve.
13. Remove the protective cap from the Series 749 Auto
Drain.
14. Pull up on the auto drain knob until it is set in the “UP”
position. Verify that there is pressure on the piston gauge.
14a. Open the manual pull station, and bleed off any air
that is present.
14b. Close the manual pull station.
15. Replace the protective cap over the auto drain knob.
16. CLOSE THE SOLENOID BY RESETTING THE
PANEL.
NOTICE
• If the solenoid is closed unintentionally, it must be reset.
• Follow steps 16 and 17 to bleed off the pressure and reset the solenoid.
¹⁄₄-inch
Ball Valve
¹⁄₄-inch
Ball Valve
Auto Drain
Protective
Cap
•Make sure the protective cap is replaced on the auto drain knob to avoid accidental
contact.
Hitting the knob will cause the valve to trip, resulting in property damage.
Auto Drain
Knob
Auto Drain
Protective
Cap
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17. For water pressures greater than 30 psi (207
kPa): Open and then immediately close the ¹⁄₄-inch ball
valve located between the Series 776 and the solenoid.
Confirm that there is zero pressure between the Series
776 and the solenoid. NOTE: Residual pressure between
0 psi and 30 psi (0 kPa – 207 kPa) is acceptable.
17a. For water pressures lower than 30 psi (207
kPa): Move on to step 18.
18. If a Series 746 Dry Accelerator is used, open the ¹⁄₄-
turn vent ball valve on the accelerator.
18a. Open the isolation ball valve on the Series 746 Dry
Accelerator.
18b. Close the ¹⁄₄-turn vent ball valve on the Series 746
Dry Accelerator. This will set the accelerator.
19. Observe the system air pressure over a 24-hour period
to confirm system integrity. If there is degradation in sys-
tem air pressure, find the leaks and correct. NOTE: NFPA
requires less than 2-psi (14-kPa) leakage in 24 hours.
20. Confirm that the alarm line ball valve is open.
21. Open the water supply main drain valve.
¹⁄₄-inch
Ball Valve
Accelerator
¹⁄₄-turn
Vent Ball Valve
Accelerator
Isolation
Ball Valve
•Take precautions when opening the water supply main control valve, since water
will flow from all open system valves.
Failure to do so could result in personal injury and property damage.
Accelerator
¹⁄₄-turn
Vent Ball Valve
Alarm Line
Ball Valve
Water Supply
Main Drain
Valve
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22. Open the water supply’s main control valve slowly
until a steady flow of water flows from the open water
supply main drain valve.
23. When a steady flow of water occurs, close the water
supply main drain valve.
24. Confirm that there is no leakage from the drip check
located in the alarm line’s piping.
24a. If water is flowing from the drip check, close the
water supply’s main control valve, and start over at step 1.
Refer to the “Troubleshooting” section on page 34.
25. Open the water supply’s main control valve fully.
26. Record the system air pressure and water supply
pressure.
27. Ensure all valves are in their normal operating posi-
tions (refer to table below).
28. Notify the authority having jurisdiction, remote sta-
tion alarm monitors, and those in the affected area that
the system is in service.
Water Supply's
Main Control
Valve
Water Supply
Main Drain
Valve
Drip
Check
Valve Normal Operating Position
Piston Charge Line Ball Valve Open
Alarm Line Ball Valve Open
Alarm Test Ball Valve Closed
Alarm Drain Ball Valve Closed
Water Supply's
Main Control
Valve
Water Supply's
Main Control
Valve
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EXTERNAL INSPECTION
Weekly Inspection
1. Perform a visual inspection on the valve and trim on a
weekly basis. NOTE: If the preaction system is equipped
with a low-pressure alarm, monthly inspections may be
sufficient. Consult with the local authority having jurisdic-
tion for specific requirements.
Monthly Inspection
1. Record the system air pressure and water supply pres-
sure. Confirm that the water supply pressure is in the
range of normal pressures observed in the area. Signifi-
cant loss in water supply pressure could indicate an
adverse condition in the water supply. Confirm the proper
water-to-air ratio is being maintained.
2. Confirm that there is no leakage from the intermediate
valve chamber. No water or air should flow from the drip
check.
3. Check for mechanical damage or corrosion. If found,
replace any affected parts.
4. Confirm that the preaction valve and trim are not sub-
ject to freezing temperatures.
5. Verify that all valves are in their normal operating posi-
tions (refer to table below).
6. If the system includes a Series 746 Dry Accelerator,
record the pressure in the accelerator’s air chamber. This
pressure should equal the system air pressure within the
allowable tolerances of the gauges. If the air chamber’s
pressure is below the system air pressure, follow the trou-
bleshooting procedures on page 34.
•Any activities that require taking the valve out of service may
eliminate the fire protection provided.
•Before servicing or testing the system, notify the authority having
jurisdiction.
•Consideration of a fire patrol should be given in the affected areas.
Failure to follow these instructions could result in serious personal
injury and/or property damage.
NOTICE
•The owner is responsible for maintaining the fire protection system in proper
operating condition.
•It is important that the system is inspected regularly, according to proper
procedures.
•The Victaulic Series 758 Preaction Valve and trim must not be exposed to foreign
material, corrosive environments, freezing conditions, contaminated water
supplies, or any other condition that could impair proper system operation.
•Modify the frequency of inspections in the presence of any environmental
conditions that could degrade system operation.
•The National Fire Protection Association pamphlet, which describes the care and
maintenance of sprinkler systems, outlines the minimum requirements for
inspections and tests.
•The authority having jurisdiction may have additional maintenance, inspection,
and test requirements.
Valve Normal Operating Position
Piston Charge Line Ball Valve Open
Alarm Line Ball Valve Open
Alarm Test Ball Valve Closed
Alarm Drain Ball Valve Closed
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REQUIRED TESTS
Main Drain Test
Perform the main drain test on a frequency required by
the current NFPA-25 code. The authority having jurisdic-
tion in your area may require that you perform these tests
on a more frequent basis. Verify these requirements by
contacting the authority having jurisdiction in the
affected area.
1. Notify the authority having jurisdiction, remote station
alarm monitors, and those in the affected area that the
main drain test will be performed.
2. Confirm that sufficient drainage is in place for a full-
flow drain test.
3. Record the water supply pressure and system air pres-
sure.
4. Verify that the valve’s intermediate chamber is dry. No
water should flow from the drip check.
5. Verify that the system is pressurized at the proper air
pressure for the local water supply pressure.
6. Open the water supply main drain valve fully to flush
the water supply of any contaminants.
7. With the water supply main drain valve fully open,
record the water supply pressure (from the water supply
gauge) as the residual pressure.
8. Close the water supply main drain valve slowly.
9. Record the water pressures established after closing
the water supply main drain valve.
10. Compare the residual pressure reading, taken above,
to the residual pressure readings taken in previous main
drain tests. If there is degradation in the residual water
supply readings, restore the proper water supply pres-
sure.
11. Verify that all valves are in their normal operating
positions (refer to table below).
12. Confirm that there is no leakage from the valve’s inter-
mediate chamber. No water or air should flow from the
drip check.
13. Notify the authority having jurisdiction, remote sta-
tion alarm monitors, and those in the affected area that
the valve is back in service.
14. Provide test results to the authority having jurisdic-
tion, if required.
Water Flow Alarm Test
Perform the water flow alarm test on a frequency required
by the current NFPA-25 code. The authority having juris-
diction in your area may require that you perform these
tests on a more frequent basis. Verify these requirements
by contacting the authority having jurisdiction in the
affected area.
1. Notify the authority having jurisdiction, remote station
alarm monitors, and those in the affected area that the
water flow alarm test will be performed.
•Any activities that require taking the valve out of service may
eliminate the fire protection provided.
•Before servicing or testing the system, notify the authority having
jurisdiction.
•Consideration of a fire patrol should be given in the affected areas.
Failure to follow these instructions could result in serious personal
injury and/or property damage.
• Be careful not to open the system main drain valve accidentally.
Opening the system main drain valve will cause the valve to operate, resulting in
property damage.
Water Supply
Main Drain
Valve
Valve Normal Operating Position
Piston Charge Line Ball Valve Open
Alarm Line Ball Valve Open
Alarm Test Ball Valve Closed
Alarm Drain Ball Valve Closed
• Be careful not to open the system main drain valve accidentally.
Opening the system main drain valve will cause the valve to operate, resulting in
property damage.
Water Supply
Main Drain
Valve
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2. Open the water supply main drain valve fully to flush
the water supply of any contaminants.
3. Close the water supply main drain valve.
4. Close the alarm line ball valve.
5. Open the alarm test ball valve. Confirm that mechanical
and electrical alarms provided are activated and that
remote monitoring stations, if provided, receive an alarm
signal.
6. Close the alarm test ball valve after proper operation of
all alarms is verified.
7. Open the alarm drain ball valve, as shown above.
8. Verify that all alarms stopped sounding, that the alarm
line drained properly, and that remote station alarms reset
properly.
Water Supply
Main Drain
Valve
Water Supply
Main Drain
Valve
Alarm Line
Ball Valve
Alarm Test
Ball Valve
Alarm Test
Ball Valve
Alarm Drain
Ball Valve
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