Technical data

TECHNICAL DATA
March 28, 2013
Dry 120e
DRY VALVE
MODEL F-1
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Telephone: [phone] Technical Services: 877-384-5464 Fax: [phone] Email: [e-mail]
bar/wrench, part number 02977BM.
11. Close all auxiliary drains, the system test valve, and the priming water level test
valve on the dry valve trim. The main drain (located on the inlet of the dry valve)
should remain open.
12. If equipped with a Viking accelerator and external anti-flood device:
Close the ½” (15 mm) anti-flood isolation valve.
Observe the air pressure gauge on top of the accelerator. The gauge must
read zero before the accelerator will automatically reset. It may be necessary
to loosen, remove, and re-install (use the appropriate wrench) the air gauge to
vent trapped air pressure from the upper chamber.
13. Open the dry system air supply and establish desired system pressure. See Table
3 for suggested air pressure to water pressure settings. NEVER EXCEED 60 PSI
(4.1 bar) AIR PRESSURE.
14. Verify that the intermediate chamber of the dry valve is free of water. No water
should flow from the drip check when the plunger is pushed.
15. If equipped with a Viking accelerator and external anti-flood device: When pressure on the accelerator air pressure gauge
equals the system set pressure, OPEN and secure the ½” (15 mm) anti-flood isolation valve.
16. Slowly open the water supply main control valve.
17. When flow is developed from the main drain, CLOSE the main drain valve.
18. Fully open the water supply main control valve.
19. Secure all valves in their normal operating position.
20. Notify Authorities Having Jurisdiction and those in the affected area that the system is in service.
5. OPERATION (Refer to Figure 3)
The clapper (5) and air plate (11) assemblies combine to form a oating member assembly. With the clapper assembly (5) latched
closed, system air pressure forces the member assembly down, sealing the water seat (16) from the intermediate chamber. When
a sprinkler operates, the system air pressure is reduced. When system air pressure is reduced to the differential tripping point of the
valve, water supply pressure in the inlet chamber lifts the member assembly off the water seat (16) and ows into the intermediate
chamber. As the member assembly continues to rise, the hook assembly (15) is forced against socket set screw (23), which causes
the hook assembly (15) to pivot on hook rod (6b) and unlatch the clapper. The clapper is spring loaded and swings to a full-open
locked position (see Figure 2-A).
When using the optional accelerator, the accelerator senses the system air pressure drop and trips. Upon tripping, the accelerator
allows the system air pressure to enter the dry valve intermediate chamber. This immediately destroys the differential causing the
member assembly to rise faster.
The intermediate chamber is normally at atmospheric pressure and is connected to the alarm line. When the valve trips, the interme-
diate chamber and alarm line are pressurized with system water pressure, activating alarms connected to the dry valve trim.
6. INSPECTIONS, TESTS AND MAINTENANCE
NOTICE: THE OWNER IS RESPONSIBLE FOR MAINTAINING THE FIRE PROTECTION SYSTEM AND DEVICES IN PROPER
OPERATING CONDITION.
The Viking Model F-1 Dry Valve and trim must be kept free of foreign matter, freezing conditions, corrosive atmospheres, contami-
nated water supplies, and any condition that could impair its operation or damage the device.
It is imperative that the system be inspected and tested on a regular basis. The frequency of the inspections may vary due to con-
taminated water supplies, corrosive water supplies, corrosive atmospheres, as well as the condition of the air supply to the system.
For minimum maintenance and inspection requirements, refer to NFPA 25. In addition, the Authority Having Jurisdiction may have
additional maintenance, testing, and inspection requirements that must be followed.
WARNING: ANY SYSTEM MAINTENANCE WHICH INVOLVES PLACING A CONTROL VALVE OR DETECTION SYSTEM OUT
OF SERVICE MAY ELIMINATE THE FIRE PROTECTION CAPABILITIES OF THAT SYSTEM. PRIOR TO PROCEEDING, NOTIFY
ALL AUTHORITIES HAVING JURISDICTION. CONSIDERATION SHOULD BE GIVEN TO EMPLOYMENT OF A FIRE PATROL IN
THE AFFECTED AREAS.
I. INSPECTION
Weekly inspection is recommended. If the system is equipped with a low air (or nitrogen) alarm, monthly inspections may be
adequate.
1. Check pressure gauges located on the supply side and system side of the dry valve. Verify that the proper ratio of air (or
nitrogen) pressure to water supply pressure is being maintained (refer to Table 3).
a.
b.
Table 3 - Air Pressure Settings
Maximum
Water
Pressure
Minimum Maximum
PSI bar PSI bar PSI bar
50 3.45 15 1.03 25 1.72
75 5.17 20 1.38 30 2.07
100 6.90 25 1.72 35 2.41
125 8.62 30 2.07 45 3.10
150 10.34 35 2.41 50 3.45
175 12.07 45 3.10 60 4.14