Victaulic FireLock NXT 769 Series User manual

WARNING
Failure to follow instructions and warnings can cause product•
failure, resulting in serious personal injury and property
damage.
Read and understand all instructions before attempting to•
install any Victaulic piping products.
Wear safety glasses, hardhat, and foot protection.•
Save this installation, maintenance, and testing manual for•
future reference.
If you need additional copies of any literature, or if you have any
questions concerning the safe installation and operation of this
product, contact Victaulic, P.O. Box 31, Easton, PA 18044-0031,
USA, Telephone: 1-800 PICK VIC, e-mail: [e-mail].
WARNING
HANG THESE INSTRUCTIONS ON THE
INSTALLED VALVE FOR EASY FUTURE REFERENCE
with Series 767 Electric/Pneumatic Actuator
INSTALLATION, MAINTENANCE, AND TESTING MANUAL I-769P-EPA
FireLock NXT™ Preaction Valve
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

TABLE OF CONTENTS
Hazard Identification ......................................1
Installer Safety Instructions .................................2
General ..............................................2
Maintenance and Testing .................................2
Introduction .............................................3
Trim Dimensions .........................................3
Exploded View Drawing – Trim Components ....................4
Exploded View Drawing – Internal Valve Components..............5
Section View Drawing and Description –
Series 767 Electric/Pneumatic Actuator ......................6
Section View Drawing and Description –
Series 746-LPA Dry Accelerator............................7
Air Supply Requirements ...................................8
Compressor Sizing ......................................8
Base or Riser-Mounted Air Compressors .....................8
Shop Air or Tank-Mounted Air Compressors...................8
Victaulic Series 757 Regulated Air Maintenance
Trim Assembly (AMTA) Option ...........................8
Victaulic Series 757P Air Maintenance Trim Assembly
(AMTA) with Pressure Switch Option ......................9
Compressor Requirements and Settings for
Series 769 FireLock NXT Preaction Valves Installed
with Series 746-LPA Dry Accelerators .....................9
Settings for Air Supervisory Pressure Switches and
Alarm Pressure Switches ...............................9
Remote System Test Valve Requirements.....................9
Important Installation Information ...........................10
Valve/Trim Installation ....................................10
Compression Fitting and Tube Installation ...................11
Hydrostatic Testing ......................................11
Placing the System in Service ..............................12
External Inspection ......................................18
Weekly Inspection .....................................18
Monthly Inspection ....................................18
Required Tests..........................................19
Main Drain Test .......................................19
Water Flow Alarm Test ..................................21
Water Level and Low Air Alarm Tests .......................22
Required Operational (Trip) Tests............................26
Partial Operational (Trip) Test.............................26
Full Operational (Trip) Test ...............................28
Required Internal Inspection ...............................29
Maintenance ...........................................32
Removing and Replacing the Clapper Seal...................32
Removing and Replacing the Clapper Assembly...............34
Installing the Cover Plate Gasket and Cover Plate..............36
Removing and Replacing the Diaphragm Assembly ............37
Replacing the Strainer Screen for Series 767
Electric/Pneumatic Actuators ...........................38
Troubleshooting – Series 767 Electric/Pneumatic Actuator .........39
Troubleshooting – Series 746-LPA Dry Accelerator...............39
Troubleshooting – System .................................39
HAZARD IDENTIFICATION
Definitions for identifying the various hazard levels are
provided below. When you see this symbol, be alert to the
possibility of personal injury. Carefully read and fully
understand the message that follows.
WARNING
The use of the word “WARNING” identifies the presence of•
hazards or unsafe practices that could result in death or seri-
ous personal injury if instructions, including recommended
precautions, are not followed.
CAUTION
The use of the word “CAUTION” identifies possible hazards or•
unsafe practices that could result in personal injury and product
or property damage if instructions, including recommended pre-
cautions, are not followed.
NOTICE
The use of the word “NOTICE” identifies special instructions•
that are important but not related to hazards.
I-769P-EPA _1
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

INSTALLER SAFETY INSTRUCTIONS
WARNING
An experienced, trained installer must install this product in accordance with all instructions. These•
instructions contain important information.
Depressurize and drain the piping system before attempting to install, remove, adjust, or maintain any•
Victaulic piping products.
Failure to follow these instructions can cause product failure, resulting in serious personal injury and/or
property damage.
GENERAL
1. Read and understand all instructions and refer to the trim
diagrams before proceeding with the installation, maintenance,
and testing of this Victaulic Series 769 FireLock NXT Preaction
Valve.
2. Inspect the shipment. Make sure all components are included in
the shipment and that all necessary tools are available for installa-
tion.
3. Use only recommended accessories. Accessories and equip-
ment that are not approved for use with this dry valve may cause
improper system operation.
4. Wear safety glasses, hardhat, foot protection, and hearing pro-
tection. Wear hearing protection if you are exposed to long periods
of noisy job-site operations.
5. Prevent back injury. Larger and pre-trimmed valves are heavy and
require more than one person or mechanical lifting equipment to
position and install the assembly. Always practice proper lifting
techniques.
6. Avoid using electrically powered tools in dangerous environ-
ments. When using electrically powered tools for installation, make
sure the area is moisture-free. Keep the work area well lit, and
allow enough space to accommodate proper installation of the
valve, trim, and accessories.
7. Watch for pinch points. Do not place fingers under the valve body
where they could be pinched by the weight of the valve. Use cau-
tion around spring-loaded components (i.e. clapper assembly).
8. Keep work areas clean. Cluttered areas, benches, and slippery
floors can create hazardous working conditions.
9. PROTECT THE SYSTEM FROM FREEZING CONDITIONS. THE
VALVE AND SUPPLY PIPING MUST BE PROTECTED FROM
FREEZING TEMPERATURES AND MECHANICAL DAMAGE.
10. IF THE INLET WATER SUPPLY IS INTERRUPTED FOR ANY
REASON, AND SYSTEM SUPPLY PRESSURE TO THE VALVE
DECREASES, MAKE SURE THE DIAPHRAGM CHARGE LINE IS
FULLY PRESSURIZED BEFORE PLACING THE SYSTEM BACK
IN SERVICE.
MAINTENANCE AND TESTING
1. Notify the authority having jurisdiction. Always notify the author-
ity having jurisdiction before performing any maintenance that
eliminates the fire protection provided by the system.
2. Follow NFPA requirements for system testing and inspection
schedules. The building owner or their representative is responsi-
ble for inspecting the system in accordance with current NFPA-25
requirements or in accordance with the requirements of the local
authority having jurisdiction (whichever is more stringent).
3. Depressurize and drain the system completely before performing
any maintenance. Water under pressure can cause the cover plate
to blow off during removal if the system is not depressurized and
drained completely.
4. Protect the valve from freezing temperatures, foreign matter,
and corrosive atmospheres. Any condition that might degrade the
system or affect system performance must be avoided.
I-769P-EPA _2
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

INTRODUCTION
The following instructions are a guide for proper installation of Victaulic Series 769 FireLock NXT Preaction Valves. These instructions involve pipe
that is properly prepared and grooved in accordance with current Victaulic specifications.
NOTICE
Drawings and/or pictures in this manual may be exaggerated for clarity.•
This product and this installation, maintenance, and testing manual contain trademarks, copyrights, and/or patented features that are the•
exclusive property of Victaulic.
TRIM DIMENSIONS
THE 4-INCH/114.3-MM CONFIGURATION IS SHOWN BELOW. 1½ – 2-INCH/48.3 – 60.3-MM CONFIGURATIONS CONTAIN ¾-INCH/19-MM DRAIN VALVES.
2 ½ – 3-INCH/73.0 – 88.9-MM CONFIGURATIONS CONTAIN 1¼-INCH/31-MM DRAIN VALVES. 4 – 8-INCH/114.3 – 219.1-MM CONFIGURATIONS CONTAIN 2-INCH/50-MM DRAIN VALVES.
A
*A1
B
*B1
G
F
D
*D1
C
Full Open *E1
E
J
K
H
Size Dimensions – inches/mm
Aprx. Weight Ea.
lbs/kg
Nominal
Size
inches
mm
Actual
Out.Dia.
inches
mm AA1* BB1* C D D1* EE1* F G H J K
Without
Trim
With
Trim
1½
40
1.900
48.3
9.00
228.60
16.43
417.32
28.00
711
42.75
1085
13.75
349
16.00
406
15.00
381
5.25
133
8.50
215
9.50
241
24.50
622
3.04
77. 21
9.17
232.91
6.98
177. 29
16.7
7.6
43.0
19.5
2
50
2.375
60.3
9.00
228.60
16.43
417.32
28.00
711
42.75
1085
13.75
349
16.00
406
15.00
381
5.25
133
8.50
215
9.50
241
24.50
622
3.04
77. 21
9.17
232.91
6.98
177. 29
17.0
7.7
43.0
19.5
2 ½
65
2.875
73.0
12.61
320.29
16.50
419.10
31.25
793
45.75
1162
13.50
342
16.25
412
18.00
457
5.25
133
9.00
228
9.75
247
22.75
577
3.90
99.06
10.50
266.70
6.93
176.02
41.0
18.7
65.0
29.5
76.1 mm 3.000
76.1
12.61
320.29
16.50
419.10
31.25
793
45.75
162
13.50
342
16.25
412
18.00
457
5.25
133
9.00
228
9.75
247
22.75
577
3.90
99.06
10.50
266.70
6.93
176.02
41.0
18.7
65.0
29.5
3
80
3.500
88.9
12.61
320.29
16.50
419.10
31.25
793
45.75
1162
13.50
342
16.25
412
18.00
457
5.25
133
9.00
228
9.75
247
22.75
577
3.90
99.06
10.50
266.70
6.93
176.02
41.0
18.7
65.0
29.5
4
100
4.500
114. 3
15.03
381.76
19.78
502.41
32.75
831
47. 50
1206
15.00
381
16.25
412
20.75
527
5.50
139
9.00
228
11. 2 5
285
22.75
577
6.25
158.75
9.62
244.34
8.46
214.88
59.0
26.7
100.0
43.3
165.1 mm 6.500
165.1
16.00
406.40
22.00
558.80
32.75
831
47. 50
1206
15.50
393
17. 25
438
22.25
565
6.00
152
8.50
215
11. 50
292
21.75
552
6.20
157.48
9.62
244.34
8.84
224.53
80.0
36.2
121.0
54.8
6
150
6.625
168.3
16.00
406.40
22.00
558.80
32.75
831
47. 50
1206
15.50
393
17. 25
438
22.25
565
6.00
152
8.50
215
11. 50
292
21.75
552
6.20
157.48
9.62
244.34
8.84
224.53
80.0
36.2
121.0
54.8
8
200
8.625
219.1
17. 50
444.50
22.94
582.67
32.50
825
47.00
1193
16.75
425
20.00
508
25.50
647
7.0 0
177
8.75
222
13.00
330
20.25
514
6.05
153.67
9.40
238.76
10.21
259.33
122.0
55.3
163.0
73.9
NOTES:
The “A” dimension coupling is not shown in order to clarify dimensional callouts.
Components shown as dotted lines denote optional equipment.
* Measurements denoted with an asterisk take optional equipment into account.
Optional drain connection kit is shown for reference and takeout dimensions.
I-769P-EPA _3
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

EXPLODED VIEW DRAWING – TRIM COMPONENTS
SERIES 769 FIRELOCK NXT PREACTION VALVE – DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE TRIM
(OPTIONAL ACCESSORIES ALSO SHOWN)
VNIIPO
2
3
From Water
Supply
30
1
11
20
22
24
14
27
13
21
16
19
21
17
18
5
21
15
6
10
23
26
25
12
8
4
29
28
7
9
From System
Air Feed
To System
NOTE: When installing the optional Series 746-LPA Dry Accelerator,
relocate the auto vent to the location of the indicated plug.
A
Location
B
To Drip Cup
Location B
To Drip
Cup
Location
B
To Drip
Cup
Location
Note 1
Bill of Materials
1 Series 769 FireLock NXT Preaction Valve
2FireLock Rigid Coupling (Optional/Sold
Separately – Comes Standard when VQR
Assembly is Ordered)
3Water Supply Main Control Valve
(Optional/Sold Separately – Comes
Standard when VQR Assembly is Ordered)
4Drain Swing Check Valve
5Drip Cup with Cap
6Alarm Pressure Switch (Optional/Sold
Separately – Comes Standard when VQR
Assembly is Ordered)
7Series 729 Drip Check Valve
8Diaphragm-Charge-Line Ball Valve
(Normally Open)
93-in-1 Strainer/Check/Restrictor
Assembly
10 Series 760 Water Motor Alarm
(Optional/Sold Separately)
11 Alarm Test Ball Valve
12 Diaphragm-Charge-Line Pressure
Gauge (0-300 psi/0-2068 kPa/0-20.7 Bar)
13 Series 749 Auto Drain
14 Series 767 Electric/Pneumatic Actuator
15 Air Manifold
16 Air Supervisory Pressure Switch
(Optional/Sold Separately – Comes
Standard when VQR Assembly is Ordered)
17 System Pressure Gauge
(0-80 psi/0-552kPa/0-5.5 Bar with Retard
18 Water Supply Main Drain Valve - Flow Test
19 Water Supply Pressure Gauge
(0-300 psi/0-2068 kPa/0-20.7 Bar)
20 Drain Connection Kit (Optional/Sold
Separately – Comes Standard when VQR
Assembly is Ordered)
21 Gauge Valve
22 System Main Drain Valve
23 Series 755 Manual Pull Station
24 Series 748 Ball Check Valve
25 Series 746-LPA Dry Accelerator
(Optional/Sold Separately)
26 Upper Chamber Strainer (100 Mesh)
27 Upper Chamber Pressure Gauge for
Series 767 Electric/Pneumatic Actuator
28 Auto Vent for Series 767 Electric/
Pneumatic Actuator
29 Upper Chamber Inlet Restrictor
.032-inch) for Series 767 Electric/
Pneumatic Actuator
30 Upper Chamber Check Valve (¼-inch)
for Series 767 Electric/Pneumatic Actuato
)
r
NOTE 1: Connection point for the Series 75D Water Column Device Kit
For information regarding installation of the Series 75B Supplemental Alarm Device or the Series 7C7 Air Maintenance/Compressor Assembly
(not shown), refer to the instructions supplied with the product.
I-769P-EPA _4
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

EXPLODED VIEW DRAWING – INTERNAL VALVE COMPONENTS
Clapper
Seal
Diaphragm
Assembly
Latch
Clapper
Seat
NOTE: VALVE IS SHOWN ABOVE IN THE “SET” POSITION
Exaggerated for Clarity
1
12
11
17
17
11
21
20
9
4
3
10
18
19
7
8
15
16
14
13
2
5
6
Bill of Materials
1 Valve Body 12 Cover Plate
2Clapper 13 Cover Plate Gasket
3Clapper Seal 14 Cover Plate Bolts*
4Seal Ring 15 Latch
5Seal Washer 16 Latch Spring
6Seal Retaining Ring 17 Latch Shaft Bushing and O-Ring (Qty. 2)
7Seal Assembly Bolt 18 Diaphragm
8Bolt Seal 19 Diaphragm Cover
9Clapper Spring 20 Diaphragm Cover Cap Screws (Qty. 8)
10 Clapper Shaft 21 Latch Shaft
11 Clapper Shaft Bushing and O-Ring (Qty. 2)
* NOTE: The 1½-inch/48.3-mm and 2-inch/60.3-mm valve sizes contain washers under the heads of
the cover plate bolts.
I-769P-EPA _5
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

SECTION VIEW DRAWING AND DESCRIPTION –
SERIES 767 ELECTRIC/PNEUMATIC ACTUATOR
The Series 767 Electric/Pneumatic Actuator is a single-unit device
used in the actuation of Series 769 FireLock NXT Preaction Valves with
double-interlocked, electric/pneumatic release trim.
Diaphragms separate the Series 767 into four chambers. The upper
and upper-middle chambers control the actuation, while the lower and
lower-middle chambers act as the water control valve.
During system charging, air pressure enters the upper-middle chamber
of the Series 767 (entry point not shown). Pulling up on the Auto Vent,
which is located on the Series 767 trim, sets the air pressure in this
(upper-middle) chamber. Water supply pressure from the diaphragm
charge line enters the upper chamber, and the normally closed sole-
noid, which is built into the Series 767, sets the water pressure. THERE
IS NO NEED TO ACTIVATE THE SOLENOID TO SET THE SYSTEM.
System air pressure in the upper-middle chamber exerts a closing
force on the diaphragm in the middle chamber of the Series 767.
Additionally, the water supply pressure exerts a closing force on the
middle diaphragm through a piston that connects the upper and middle
diaphragms. These pressures close the water path of the lower-middle
chamber.
When the diaphragm charge line is open, water enters the lower cham-
ber of the Series 767; this water flows to the lower-middle chamber
through the inlet. The middle diaphragm traps water in the lower-middle
chamber. Supply water pressure in the upper chamber and system air
pressure in the upper-middle chamber hold the lower-middle diaphragm
assembly closed.
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 outlet of the Series 767,
and the supply water pressure creates the water seal.
When the system air pressure decays to 7 psi/48 kPa/0.5 Bar, the Auto
Vent’s compression spring exerts a force greater than the air pressure
in the upper-middle chamber. The Auto Vent opens, and all air pres-
sure in the upper-middle chamber evacuates. During this condition, the
Series 767 will not actuate, since water pressure in the upper chamber
maintains a closing force on the water seal of the lower-middle chamber.
Likewise, if there is an electrical detection event, the solenoid on the
upper chamber will activate and cause the upper chamber’s water pres-
sure to release. The Series 767 will not actuate, since the upper-middle
chamber’s air pressure exerts a closing force on the lower-middle
chamber’s water seal.
The Series 767 will actuate only when an electrical detection and loss
of system air pressure occur. During this condition, the closing force on
the lower-middle diaphragm’s water seal is removed, and the lower-mid-
dle chamber’s water pressure releases. This allows the lower diaphragm
to lift and water to flow from the Series 767’s inlet to the outlet. This
water flow releases water pressure from the preaction valve’s diaphragm
and allows the diaphragm to retract. The preaction valve’s clapper
opens, and water flows into the sprinkler system
.
10
11
89
7
15
26
18
19
16
17
To Drain
To Drain
Water In
21
22
20
Exaggerated for Clarity
Water In
5
23
6
4
3
1
25
24
2
Plunger shown for
reference only
Bill of Materials
1 Upper Chamber 14 Auto Vent Screw
2Upper Diaphragm 15 Outlet Orifice
3Upper-Middle Chamber 16 Gasket
4Middle Diaphragm 17 Upper Piston
5Lower-Middle Chamber 18 Isolating Diaphragm
6Lower Diaphragm 19 Lower Piston
7Strainer Assembly 20 Middle Spring
8Strainer O-Ring 21 Lower Spring
9Strainer Screen 22 Outlet Eyelet
10 Lower Chamber 23 Inlet Eyelet
11 Solenoid Valve 24 Isolating Diaphragm Retainer
12 Auto Vent 25 Upper Diaphragm Retainer
13 Auto Vent Sleeve 26 Outlet Orifice O-Ring
14 13
12
The auto vent, shown above, is
located in the trim of the upper-
middle chamber. NOTE: The auto
vent is shown in the set position
with the sleeve resting on the body
and the screw elevated.
I-769P-EPA_6
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

SECTION VIEW DRAWING AND DESCRIPTION –
SERIES 746-LPA DRY ACCELERATOR
The Series 746-LPA Dry Accelerator is a quick-opening device, which When a rapid loss of system air pressure occurs, such as an open
exhausts air from the Series 767 Electric/Pneumatic Actuator to speed sprinkler, air escapes from the closing chamber faster than it escapes
valve operation. from the opening chamber. As the sprinkler system’s pressure continues
to decay, a differential pressure develops across the diaphragm. When
A diaphragm separates the Series 746-LPA Dry Accelerator into two this differential pressure reaches 3 – 5 psi/21 – 34 kPa/0.2 – 0.3 Bar,
chambers. The closing chamber contains a compression spring, which the opening chamber’s pressure overcomes the compression spring’s
maintains the chamber in the closed position. The closed position is closing force, causing the closing chamber to open to the atmosphere.
maintained as long as the pressure differential between the opening and The closing chamber opens immediately and releases pressure from the
closing chambers is less than 3 psi/21 kPa/0.2 Bar. actuator, resulting in valve operation.
When the system introduces air pressure into the dry accelerator, air NOTE: The Series 746-LPA Dry Accelerator must be used only on
enters the closing chamber and passes through a check valve to the systems operating below 30 psi/206 kPa/2.1 Bar of air. If air pressure
opening chamber. The check valve, which allows flow into the open- higher than 30 psi/206 kPa/2.1 Bar is required, the Series 746 Dry
ing chamber, prevents pressure from escaping the opening chamber. Accelerator should be used.
Therefore, air can escape only through the restrictor.
Exaggerated for Clarity
To Pressure
Gauge
Air Inlet
CROSS-SECTION WITH UPPER CHAMBER ROTATED
45° AND BOLT REMOVED FOR CLARITY
15
1
14
13
11
12
8
6
7
10
2
3
5
4
9
4
Bill of Materials
1 Opening/Air Chamber 9O-Ring
2Restrictor 10 Seal Support
3Piston 11 Closing Chamber Seal
4O-Ring 12 Button-Head Cap Screw
5Diaphragm 13 Washer
6Actuator Shaft 14 Adjustable Seat
7Closing Chamber 15 Check Valve
8Compression Spring
I-769P-EPA _7
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

AIR SUPPLY REQUIREMENTS
The required air pressure for Series 769 FireLock NXT Preaction Valves
is 13psi/90 kPa/0.9 Bar minimum, regardless of the system supply wate
pressure. Normal air pressure should not exceed 18 psi/124kPa/1.2 Bar
Failure to maintain air pressure within the 13 psi/90 kPa/0.9 Bar to
18psi/124 kPa/1.2 Bar range may reduce system operation response
time.
Systems with air pressure higher than 18 psi/124kPa/1.2 Bar may
require the addition of a Series 746-LPA Dry Accelerator. NOTE: The
Series 746-LPA Dry Accelerator must be used only on systems oper-
ating below 30 psi/206 kPa/2.1 Bar of air. If air pressure higher than
30 psi/206 kPa/2.1Bar is required, the Series 746 Dry Accelerator
should be used.
If multiple Series 769 FireLock NXT Preaction Valves are installed with
a common air supply, isolate the systems with a spring-loaded, soft-
seated ball check valve to ensure air integrity for each system. Good
practice is to include a ball valve for isolation and service of each
individual system.
Set the air pressure to the required system air pressure. Air pressure
differing from the required system air pressure could reduce system
operation response time.
The engineer/system designer is responsible for sizing the compressor
so that the entire system is charged to the required air pressure within
30 minutes. DO NOT oversize the compressor to provide more airflow.
An oversized compressor will slow down or possibly prevent valve
operation.
If the compressor fills the system too fast, it may be necessary to
restrict the air supply. Restricting the air supply will 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.
r
.
COMPRESSOR SIZING
0
2
4
6
8
10
12
System Capacity (in gallons)
Required Flow Rate (CFM)
COMPRESSOR REQUIREMENTS
550 300
50
800
1050 1300 1550 1800
20 psi/138 kPa
13 psi/90 kPa
BASE OR RISER-MOUNTED AIR COMPRESSORS
For base or riser-mounted air compressors, the recommended air
pressure of 13psi/90 kPa/0.9 Bar is the “on” or “low” pressure set-
ting for the compressor. The “off” or “high” pressure setting should be
18 psi/124 kPa/1.2 Bar.
When a base or riser-mounted air compressor supplies air to a Series
769 FireLock NXT Preaction Valve, it is not necessary to install the
Victaulic Series 757 Regulated Air Maintenance Trim Assembly (AMTA).
In this case, the air line of the compressor connects to the trim at the
fitting where the Series 757 Regulated AMTA is normally installed (refer
to the applicable trim drawing). If the compressor is not equipped with
a pressure switch, the Series 757P Air Maintenance Trim Assembly with
Pressure Switch should be installed.
SHOP AIR OR TANK-MOUNTED AIR COMPRESSORS
In the event a compressor becomes inoperative, a properly sized tank-
mounted air compressor provides the greatest protection for systems.
When shop air or a tank-mounted air compressor is used, the Series
757 Regulated AMTA must be installed. The Series 757 Regulated
AMTA provides proper air regulation from the air reservoir to the
sprinkler system.
For tank-mounted air compressors, the recommended air pressure
of 13 psi/90 kPa/0.9 Bar should be used as the set point for the air
regulator. The “on” pressure of the compressor should be at least
5 psi/34 kPa/0.3 Bar above the set point of the air regulator.
VICTAULIC SERIES 757 REGULATED AIR MAINTENANCE TRIM
ASSEMBLY (AMTA) OPTION
NOTICE
Victaulic recommends a maximum of two Series 769 FireLock•
NXT Preaction Valves per Series 757 Regulated AMTA.
16
5
4
2
3
Bill of Materials
1 ⁄"/3.2 mm Restrictor
2Slow Fill Ball Valve (Normally Open)
3Air Regulator
4Strainer (100 Mesh)
5Spring-Loaded, Soft-Seated
Ball Check Valve
6Fast Fill Ball Valve (Normally Closed)
I-769P-EPA _8
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

VICTAULIC SERIES 757P AIR MAINTENANCE TRIM ASSEMBLY
(AMTA) WITH PRESSURE SWITCH OPTION
NOTICE
Victaulic recommends a maximum of two Series 769 FireLock•
NXT Preaction Valves per Series 757P AMTA with Pressure
Switch.
Refer to the I-757P Air Maintenance Trim Assembly with•
Pressure Switch Installation Instructions, supplied with the
product, for complete installation, electrical, and pressure
switch adjustment information.
5
2
12
7
8
15
10
16
9
6
4
1
13
3
14
11
TO
SYSTEM
FROM
COMPRESSOR
Bill of Materials
Item Qty. Description
1 1 Restrictor (½-inch NPT)
2 1 Strainer (½-inch NPT)
3 1 Swing Check (½-inch NPT)
4 1 Slow-Fill Ball Valve
(Normally Open)
5 1 Spring-Loaded, Soft-Seated
Check Valve
6 1 Pressure Switch
7 2 Compression Fitting, Straight
(¼-inch NPT x ¼-inch Tube)
8 1 Copper Tubing (¼-inch OD)
9 11 Close Nipple
(½-inch NPT x 1.13)
10 1 Nipple (½-inch NPT x 4.00)
11 1 90° Female Elbow (½-inch NPT)
12 4 Female Tee (½-inch NPT)
13 3 Union (½-inch NPT)
14 2 Reducing Bushing
(½-inch NPT x ¼-inch NPT)
15 1 Fast-Fill Ball Valve
(Normally Closed)
16 1 Pressure Switch Isolation Ball
Valve (Normally Open -
Lockable)
COMPRESSOR REQUIREMENTS AND SETTINGS FOR SERIES 769
FIRELOCK NXT PREACTION VALVES INSTALLED WITH SERIES
746-LPA DRY ACCELERATORS
Set the air regulator of the Series 757 Regulated AMTA to a minimum of
13 psi/90 kPa/0.9 Bar.
The Series 757P Air Maintenance Trim Assembly with Pressure
Switch MUST NOT be used on a Series 769 FireLock NXT Preaction
Valve installed with a Series 746-LPA Dry Accelerator, unless a tank
and air regulator are added.
In the event a compressor becomes inoperative, a properly sized tank-
mounted air compressor provides the greatest protection for systems
installed with a Series 746-LPA Dry Accelerator. In this situation, air
can be supplied continuously to the sprinkler system for an extended
time period. NOTE: The Series 757 Regulated AMTA should be used
with a tank-mounted air compressor to supply air to a Series 769
FireLock NXT Preaction Valve when the Series 746-LPA Dry Accelerator
is used. The use of an air regulator with a base or riser-mounted air
compressor could cause short cycling, resulting in premature wear of
the compressor.
The air regulator of the Series 757 Regulated AMTA is a relief-type
design. Any pressure in the system that is above the set point of the air
regulator will be released. Therefore, charging the air regulator above
the set point could cause premature operation of a valve installed with a
Series 746-LPA Dry Accelerator.
SETTINGS FOR AIR SUPERVISORY PRESSURE SWITCHES AND
ALARM PRESSURE SWITCHES
1. Air supervisory pressure switches are required for preaction
systems and must be set according to the following notes. NOTE:
Switches for Vic-Quick Risers are pre-set at the factory.
1a. Wire the air supervisory pressure switches to activate a
low-pressure alarm signal. NOTE: In addition, the local
authority having jurisdiction may require a high-pressure
alarm. Contact the local authority having jurisdiction for this
requirement.
1b. Set the air supervisory pressure switches to activate at
2 – 4 psi/14 – 28 kPa/0.1 – 0.3 Bar below the minimum air
pressure required (but not lower than 10 psi/69 kPa/0.7Bar).
1c. Wire the alarm pressure switch to activate a water flow alarm.
1d. Set the alarm pressure switch to activate on a pressure rise of
4 – 8 psi/28 – 55 kPa/0.3 – 0.6 Bar.
REMOTE SYSTEM TEST VALVE REQUIREMENTS
The remote system test station (inspector’s test connection) should
contain a valve that can be opened to simulate sprinkler operation.
The remote system test valve (inspector’s test connection) should be
located at the most hydraulically demanding location in the release
system. NOTE: Multiple restrictions on the remote system test valve
(inspector’s test connection) may slow the air decay rate and cause the
system to respond slower than required.
The remote system test valve (inspector’s test connection) should termi-
nate with an orifice equal to the smallest orifice in the releasing system.
The remote system test valve (inspector’s test connection) is used to
ensure that water reaches the most remote part of the system within 60
seconds.
I-769P-EPA _9
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

IMPORTANT INSTALLATION INFORMATION
1. For proper operation and approval, the Series 769 FireLock NXT
Preaction Valve must be installed in accordance with the spe-
cific trim diagrams included with the shipment. NOTE: Victaulic
provides specific trim diagrams for installations involving a Series
746-LPA Dry Accelerator.
2. Before installing the Series 769 FireLock NXT Preaction Valve,
flush the water supply piping thoroughly to remove all foreign
material.
3. Series 769 FireLock NXT Preaction Valves MUST NOT be located
in an area where the valve can be exposed to freezing tempera-
tures. In addition, the Series 769 FireLock NXT Preaction Valve
MUST NOT be located in an area where physical damage may
occur.
4. It is the system designer’s responsibility to confirm material com-
patibility of the Series 769 FireLock NXT Preaction Valve, trim, and
associated accessories when a corrosive environment or contami-
nated water is present.
5. SERIES 769 FIRELOCK NXT PREACTION VALVES MUST BE
INSTALLED ONLY IN THE VERTICAL POSITION WITH THE
ARROW ON THE BODY POINTING 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 continuous.
8. When an uninterruptible water flow alarm is required, Victaulic
recommends the use of a low-pressure alarm installed on the
diaphragm charge line downstream of the strainer/check restric-
tor. Another option is to install a Series 75B Supplemental Alarm
Device.
9. Per NFPA 13 requirements, piping must be pitched so that
systems can drain properly. For areas that are subject to high
levels of condensation, or where piping is not properly pitched, an
optional Series 75D Water Column Device kit is available to assist
in automatically draining water out of the riser.
VALVE/TRIM INSTALLATION
1. Make sure the trim drawing matches the system’s requirements.
CAUTION
Make sure the foam spacer is removed from•
inside the valve body before attempting to
install the valve.
Failure to follow this instruction could cause
improper valve operation, resulting in personal
injury and/or property damage.
2. Remove all plastic caps and foam spacers from the valve.
3. Apply a small amount of pipe joint compound or Teflon* tape to
the external threads of all threaded pipe connections. DO NOT get
any tape, compound, or other foreign material into the valve body,
pipe nipples, or valve openings.
CAUTION
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, resulting in personal injury and/or property damage.
4. Install the valve, trim, and accessories per the trim drawing.
TO ACTUATOR
TRIM
RE-LOCATE THE ACTUATOR’S
AUTO VENT ASSEMBLY TO
THE LOCATION OF THIS PLUG
5. FOR VALVES INSTALLED WITH A SERIES 746-LPA DRY
ACCELERATOR: Make sure the Series 746-LPA Dry Accelerator is
installed in accordance with the trim drawing provided. The end
with the vent seal “button” must be installed facing down (toward
the trim, as shown above).
6. Supply pressure to the diaphragm charge line by providing an
uninterrupted source of water from upstream of the main control
valve.
* Teflon is a registered trademark of the DuPont Company
I-769P-EPA _10
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

COMPRESSION FITTING AND TUBE INSTALLATION
Compression Fitting and Tube Configuration
for Auto Drain and Drip Check
Compression Fitting and Tube Configuration
for Actuator
Compression fittings and tubes are provided for connection from the
outlet of the auto drain, drip check, and actuator to the drip cup or
drain. These compression fittings and tubes must be installed, in accor-
dance with the trim drawing provided. NEVER insert a plug into the out-
let of the auto drain, drip check, or actuator in place of the compression
fitting/tube.
HYDROSTATIC TESTING
WARNING
If air testing is required, DO NOT exceed•
50 psi/345 kPa/3.4 Bar air pressure.
Failure to follow this instruction could result
in serious personal injury and/or property
damage.
The Victaulic Series 769 FireLock NXT Preaction Valve is UL Listed and
FM Approved for a maximum working pressure of 300 psi/2065 kPa/
20.7Bar and is factory tested to 600 psi/4135 kPa/41.4 Bar for all
sizes. The valve can be hydrostatically tested against the clapper at
200 psi/1380 kPa/13.8 Bar or 50 psi/345 kPa/3.4 Bar above the normal
water supply pressure (2-hour limited time period) for acceptance by
the authority having jurisdiction.
I-769 P- EPA _11
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

PLACING THE SYSTEM IN SERVICE
CAUTION
Make sure the Series 769 FireLock NXT 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 personal injury and/or property damage.
THE FOLLOWING INSTRUCTIONS APPLY TO A
SOLENOID THAT IS DE-ENERGIZED. IF THE
SOLENOID IS ENERGIZED, RESET THE PANEL
BEFORE ATTEMPTING TO PLACE 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 all system drains are shut and that the system is free
of leaks.
3a. Confirm that the system has been depressurized. The gauges
should indicate zero pressure.
4. If a Series 746-LPA Dry Accelerator is installed, confirm that the
isolation ball valve to the accelerator is closed.
4a. If a Series 746-LPA Dry Accelerator is installed, open the ¼-turn
ball vent valve.
5. Open the diaphragm-charge-line ball valve.
I-769P-EPA _12
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

Screw
(Not in “set”
position)
Seal
Compression
Fitting
Drain
Hose
Body
Spring
Stem
Screw
(In “set”
position)
Sleeve
6. Confirm that water is flowing steadily from the Auto Drain. Pull up
on the Auto Drain Sleeve, and confirm that water is flowing through
the Series 767 Electric/Pneumatic Actuator.
7. Close the diaphragm-charge-line ball valve.
8. Confirm that the alarm test ball valve is closed.
9. Charge the system with air by turning on the compressor or by
opening the fast-fill ball valve on the AMTA (fast-fill ball valve is
shown above). Charge the system to 13 psi/90 kPa/0.9 Bar mini-
mum. Refer to the “Air Supply Requirements” section.
9a. Confirm that the system is charging by observing the air pres-
sure gauge. If the gauge is not showing an increase in air
pressure, there is a leak or an opening in the line. Repair any
leaks or openings and restart the setup procedure.
10. Confirm that no water is being exhausted from the Auto Vent
of the Series 767 Electric/Pneumatic Actuator. If water is being
exhausted from the Auto Vent, continue to run air through the
system in order to remove moisture from the upper chamber of the
Series 767 Electric/Pneumatic Actuator. If a Series 746-LPA Dry
Accelerator is installed, make sure the accelerator is not flooded.
I-769P-EPA _13
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

11. When the system reaches approximately 10psi/69 kPa/0.7 Bar, and
no additional moisture is being released from the Auto Vent, pull
up on the Auto Vent Sleeve of the Series 767 Electric/Pneumatic
Actuator. NOTE: The Auto Vent Screw should seal and remain in
the set (“UP”) position.
\
12. When system air pressure is established, close the fast-fill ball
valve on the AMTA.
13. Open the slow-fill ball valve on the AMTA. NOTE: Failure to leave
the slow-fill ball valve open may allow system pressure to drop,
resulting in valve operation in the event of a system leak.
14. Open the diaphragm-charge-line ball valve. Allow water to flow
through the Auto Drain tube.
15. Open the manual pull station to bleed off any air that is present.
I-769P-EPA _14
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

16. Close the manual pull station.
17. Pull up on the Auto Drain Sleeve until the Screw is in the set
(“UP”) position. Verify that there is pressure on the gauge to the
diaphragm charge line.
18. Check the gauge on the Series 767 Electric/Pneumatic Actuator to
confirm that there is water supply pressure on the upper chamber.
19. When the diaphragm charge line is pressurized, temporarily close
the diaphragm-charge-line ball valve. Confirm that the diaphragm
charge line is maintaining pressure by observing the diaphragm-
charge-line pressure gauge.
19a. If pressure in the diaphragm charge line drops, the
diaphragm must be replaced and/or any leaks in the
diaphragm charge line must be corrected. Refer to the
“Removing and Replacing the Diaphragm Assembly” section.
19b. If pressure in the diaphragm charge line does not drop, re-
open the diaphragm-charge-line ball valve, and proceed to
the following step.
I-769P-EPA _15
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

20. If a Series 746-LPA Dry Accelerator is installed, close the ¼-turn
vent ball valve on the accelerator.
21. If a Series 746-LPA Dry Accelerator is installed, open the isolation
ball valve. This will set the accelerator.
22. Observe the system air pressure over a 24-hour period to confirm
system integrity. If there is degradation in system air pressure, find
and correct all leaks. NOTE: NFPA requires less than 1½-psi/
10-kPa/0.1 Bar leakage in 24 hours.
23. Open the water supply main drain valve.
CAUTION
Take precautions when opening the water supply main control•
valve, since water will flow from all open system valves.
Failure to follow this instruction could result in property damage.
Water Supply Main
Control Valve
24. Open the water supply main control valve slowly until water flows
steadily from the open water supply main drain valve.
I-769P-EPA _16
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

25. Close the water supply main drain valve when a steady flow of
water occurs.
26. Confirm that there is no leakage from the intermediate valve
chamber. The drip check in the alarm line should not be leaking
water or air.
Water Supply Main
Control Valve
27. If water is flowing from the drip check, close the water supply
main control valve, and start over at step 1. Refer to the
“Troubleshooting” section.
Water Supply
Main Control
Valve
28. Open the water supply main control valve fully.
29. Record the system air pressure and the water supply pressure.
30. Confirm that all valves are in their normal operating positions (refer
to the table below).
Valve
Normal Operating
Position
Diaphragm-Charge-Line Ball Valve Open
Alarm Test Ball Valve Closed
Water Supply Main Control Valve Open
Water Supply Main Drain Valve Closed
System Main Drain Valve Closed
Slow-Fill Ball Valve of the Victaulic AMTA (if applicable) Open
Fast-Fill Ball Valve of the Victaulic AMTA (if applicable) Closed
Isolation Ball Valve for Series 746-LPA Dry Accelerator (if
applicable) Open
¼-Turn Vent Ball Valve for Series 746-LPA Dry Accelerator (if
applicable) Closed
31. Notify the authority having jurisdiction, remote station alarm
monitors, and those in the affected area that the system is in
s e r v i c e .
ON A WEEKLY BASIS, WHEN THE VALVE IS RESET AFTER AN
OPERATIONAL TEST (OR AFTER ANY SYSTEM OPERATION): The
main drain valve and any low-point drain valves should be partially
opened and then closed to drain water that might be present in the
riser. Continue this procedure until all water is released. NOTE: The
optional Series 75D Water Column Kit can be installed to automate this
step.
I-769P-EPA _17
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPAINSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

EXTERNAL INSPECTION
WARNING
The building owner or their representative is responsible for•
maintaining the fire protection system in proper operating
condition.
To ensure proper system operation, valves must be inspected•
in accordance with current NFPA-25 requirements or in accor-
dance with the requirements of the local authority having
jurisdiction (whichever is more stringent). Always refer to the
instructions in this manual for additional inspection and testing
requirements.
The frequency of inspections must be increased in the pres-•
ence of contaminated water supplies, corrosive/scaling water
supplies, and corrosive atmospheres.
Depressurize and drain the piping system before attempting to•
install, remove, adjust, or maintain any Victaulic products.
Failure to follow these instructions could cause system failure,
resulting in death, serious personal injury, and property damage.
NOTICE
Any activities that require taking the valve out of service may•
eliminate the fire protection provided.
Consideration of a fire patrol should be given for the affected•
areas.
Before servicing or testing the system, notify the authority•
having jurisdiction.
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. Contact the
local authority having jurisdiction for specific requirements.
MONTHLY INSPECTION
1. Record the system air pressure and water supply pressure.
Confirm that the water supply pressure is within the range of
normal pressures observed in the area. Significant loss of 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. The drip check in the alarm line should not be leaking
water or air.
3. Inspect the valve and trim for mechanical damage and corrosion.
Replace any damaged or corroded parts.
4. Confirm that the preaction valve and trim are located in an area
that is not subject to freezing temperatures.
5. Confirm that all valves are in their normal operating positions (refer
to the table below).
Normal Operating
Valve Position
Diaphragm-Charge-Line Ball Valve Open
Alarm Test Ball Valve Closed
Water Supply Main Control Valve Open
Water Supply Main Drain Valve Closed
System Main Drain Valve Closed
Slow-Fill Ball Valve of the Victaulic AMTA (if applicable) Open
Fast-Fill Ball Valve of the Victaulic AMTA (if applicable) Closed
Isolation Ball Valve for Series 746-LPA Dry Accelerator (if
applicable) Open
¼-Turn Vent Ball Valve for Series 746-LPA Dry Accelerator (if
applicable) Closed
6. If a Series 746-LPA Dry Accelerator is installed, record the
pressure in the air chamber of the dry accelerator. The pressure
in the air chamber should equal the system air pressure within
the allowable tolerances of the gauges. If the air chamber’s pres-
sure is below the system air pressure, follow the “Troubleshooting”
section.
I-769P-EPA _18
FireLock NXT™ Preaction Valve
with Series 767 Electric/Pneumatic Actuator
SERIES 769
(DOUBLE-INTERLOCKED, ELECTRIC/PNEUMATIC RELEASE)
I-769P-EPA
INSTALLATION, MAINTENANCE, AND TESTING MANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D