2” Emergency Deluge System Description
2” Emergency Deluge System is a fixed fire protection system in which the pipe system is empty until the deluge valve operates to distribute pressurized water from open nozzles or sprinklers. Deluge systems are more complex than wet pipe and dry systems because they contain more components and equipment. The deluge valve is activated by operation of a fire detection system installed in the same area as the sprinklers (Figure 1). Various types of detection systems may be used, including smoke, heat, ultraviolet (UV), or infrared (IR) detection. The Viking deluge system can be activated by a hydraulic, pneumatic, electric, or manual release system or any combination of these release systems.
But, in all cases, the deluge valve itself is activated hydraulically. When the detection device is activated, the deluge valve is tripped and water flows
into the piping system, discharging through all spray nozzles or sprinklers simultaneously (Figure 2).
This technical manual will cover Viking deluge system design calculation, trim parts and their functions, as
well as describe the proper operation, maintenance, and repair of valves and system devices.
II. types and applications
Deluge systems are used where conditions of occupancy or special hazards require quick application of
large quantities of water. These systems are used to create a buffer zone in high-hazard areas or in areas
where fire may spread rapidly, and they can also be used to cool surfaces to prevent deformation or structural collapse or to protect tanks, process lines, or transformers against explosion. Other examples include storage or process areas containing substances having a low flash point; tanks containing combustible
solutions, equipment pits or product handling systems.
When designing a deluge system, efforts should be
made to acquire specific information regarding the hazard to be protected.
Foam-water deluge systems are those using foam-water sprinklers or spray nozzles and an air-foam concentrate which is introduced into the water at controlled rate on the system side of the deluge valve.
Foam water systems are used to control and/or extinguish fires which require a smothering and cooling agent.
Examples are: extraction plants, aircraft hangars and areas where flammable-liquid spill fires may occur.
Trimpac® Deluge Systems: TRIMPAC® is a factory assembled trim package with a specific release device
and release module (pneumatic or electric) in a metal enclosure. The standard trim normally required on
a deluge valve has been moved to a single cabinet. TRIMPAC® provides access doors for the emergency
release and alarm test valve for manual operation of these trim valves.
TRIMPAC® is equipped with priming water pressure and water supply gauge view-ports for easy monitoring of water pressures. TRIMPAC®
eliminates the installation of alarm trim piping and release trim piping at the deluge valve. The enclosure
protects trim valves from inadvertent operation. Piping (or the included stainless steel hose package) from
the valve body to the enclosure assembly allows the assembly to be installed remote of the sprinkler system riser. TRIMPAC® can be utilized for pneumatic or electric release deluge systems regardless of valve
size. A valve drain package for the deluge valve is required and is ordered based on the deluge valve size.
Refer to sections in this manual specifically for TRIMPAC®.
Some installation standards state that a discharge rate of 3,000 gpm (11,355 L/min) should not be exceeded for a single system. System size may be further limited by the water supply available to the system
and/or the hazard classification. If there is any question concerning the adequacy of the deluge system’s
coverage, seek the advice of the insurance underwriter or a qualified consulting engineering firm.
III. System requirements
Section 7.3 of NFPA 13-2007 provides the installation rules and characteristics that are unique to deluge
systems. Also, refer to NFPA 72 National Fire Alarm Code for specific requirements on the design of hydraulic, pneumatic, and electrical detection systems.
Deluge systems are required to be hydraulically calculated. Since all sprinklers are open, every sprinkler
on the system discharges water simultaneously when the deluge valve operates.
Note: The system’s area
of operation is easy to determine; it is the entire area protected by the deluge system. Chapter 22 of NFPA
13 discusses the procedures for calculating the hydraulic demand of the sprinkler system and for verifying
whether the available water supply will meet the requirements.
Viking deluge equipment is designed to allow for a variety of release devices. The release system detection device itself may be thermostatic (fixed-temperature/rate-of-temperature-rise) or manual. Releasing devices, including automatic sprinklers used as releasing devices, are listed with specific spacing requirements that must be followed. Where thermal activation is utilized, the activation temperature of the release system shall be lower than the activation temperature of the sprinkler to ensure that the releasing system
will operate before the sprinkler system. NOTE: Where heat-responsive devices are used, NFPA 13 requires a supply of spare fusible elements (at least 2 of each temperature rating) to be kept on the premises for replacement purposes.
The release system shall serve all areas that the deluge system protects to ensure that in the event of
a fire, the release system will activate and provide water to the system and the affected area. NFPA 13
requires the detection devices or systems to be automatically supervised (monitored).
All components of pneumatic, hydraulic, or electrical systems shall be compatible to ensure that all system
components function as an integrated unit. For example, in electrical systems, the solenoid valve must be
listed with the deluge valve, and the fire detection system, including the control panel. Correct coordination of the detection devices, the releasing equipment, and the control panel is imperative for prompt and
reliable operation of the system.
Manually-Operated Release System
Manually operated release systems are usually integrated into one of the other types of release systems.
NFPA 13 requires the manual release device to be a stand-alone arrangement to ensure operation, regardless of the potential failure of the associated detection system. Normally a system will incorporate a
manual release at the valve, exits, operator station, or other convenient locations to operate the system
during a fire emergency.
Release Control Panel
The release panel is an essential component for system operation and is required to be listed.
Devices for Test Purposes and Testing Apparatus
Where detection devices installed in circuits are located where not readily accessible for testing, NFPA 13
requires an additional detection device to be provided on each circuit for test purposes at an accessible location. The device shall be connected to the circuit at a point that will ensure a proper test of the circuit.
When the deluge valve operates, the sensing end of the PORV is pressurized, causing the PORV to operate (Figures 13-14). When the PORV operates, it continually vents the priming chamber to prevent the
deluge valve from resetting even if the open releasing devices close. The deluge valve can only be reset
after the system is taken out of service, and the outlet chamber of the deluge valve and associated trim
piping is depressurized and drained.
A. Deluge System Controlled by Hydraulic Release
Hydraulic release systems may utilize rate-of-temperature rise, fixed-temperature, manual releasing
devices, or combinations thereof. Hydraulic release systems are normally the least expensive of possible release systems; however, they must be installed in areas that are not subject to freezing.
Release Lines: Use galvanized steel pipe or corrosion-resistant tubing, such as copper or brass for
release lines. Do not exceed 1,000 ft. (304.8 m) of ½” (15 mm) pipe in a release-line system. In systems over this capacity, larger pipe sizing is required.
Maximum Allowable Height Of Release Line Above The Deluge Valve: Under certain conditions, the
deluge valve may be subject to water columning. To prevent this, hydraulic release system piping
must not exceed the maximum elevation allowed for hydraulic release piping above the deluge valve
as indicated in the listing. Refer to current technical data for the Viking deluge valve used.
B. Deluge System Controlled by Pneumatic Release
Pneumatic release systems may utilize rate-of-temperature-rise, fixed-temperature, manual releasing
devices, or combinations thereof. Pneumatic release systems may be used in most areas. Costs of installation and maintenance are usually higher than a comparable hydraulic release system. Valve trip-time may vary depending on the length of the release line and the air pressure maintained on the release system.
Air is commonly used in the release line where freezing is a concern.
However, air systems require a dry air supply, a means of transitioning from air to water in the release line, and a release line
maximum of 1,000 ft. The device used to accomplish the transition is Viking’s Model H-1 Pneumatic
Actuator (Figure 15). The pneumatic actuator is installed in the release line downstream from the
PORV and emergency release connections (Figure 16).