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ESFR PENDENT SPRINKLER
VK503 (K16.8)
1. DESCRIPTION
Viking Early Suppression Fast Response (ESFR) Pendent Sprinkler VK503 is a fast
response fusible element type sprinkler designed for early fire suppression. With a
16.8 (242 metric*) nominal K-Factor and special deflector, this sprinkler produces large,
high-momentum water droplets in a hemispheric pattern below the deflector. This permits penetration of the fire plume and direct wetting of the burning fuel surface while
cooling the atmosphere early in the development of a high-challenge fire.
Viking Sprinkler VK503 may be used in the protection of ordinary types of storage.
However, it is primarily intended to protect the following types of storage, which tend
to produce severe-challenge fires: palletized and solid pile storage and single, double,
multiple row, and portable open rack storage (no open-top containers or solid shelves).
Viking ESFR Pendent Sprinkler VK503 provides protection of most common storage
materials, including:
--Encapsulated or unencapsulated Class I, II, III, and IV commodities*.
--Cartoned and uncartoned unexpanded plastics*.
--Cartoned expanded plastics*.
* Refer to the Approval Charts and Commodity Selection and Design Criteria Overview for cULus
Listing and FM Approval requirements that must be followed.
In addition, some storage arrangements of rolled paper, aerosols, and rubber tires may be protected by Viking ESFR Pendent Sprinkler VK503.
2. LISTINGS AND APPROVALS
cULus Listed: Category VNWH
Successfully meets UL 1767 test standard and compliance
program for ESFR sprinklers installed in-rack storage with
high clearances to ceiling (20 ft or greater)
FM Approved: Class 2027
NYC Approved: MEA 89-92-E, Volume 41
CCCF Approved: Approved by the China Certification Center for
Fire Products (CCCF)
Refer to the Approval Charts and Commodity Selection and Design
Criteria Overview for cULus Listing and FM Approval requirements
that must be followed.
SPRINKLER GENERAL INFORMATION
ItemDescription
Sprinkler Identification
Number (SIN)
K-factor, gpm/psi
Thread Size
Sprinkler OrientationPendent
Maximum Working Pressure175 psi (12 bar)
TABLE 1
VK503
½
(lpm/bar½)16.8 (242)
3/4” NPT (20 mm BSPT)
3. TECHNICAL DATA
Specications:
Available since 2007.
Maximum Working Pressure: 175 psi (12 bar). Factory tested hydrostatically to 500 psi
(34.5 bar).
Thread size: 3/4” NPT or 20 mm BSPT
Nominal K-Factor: 16.8 U.S. (242 metric*)
* Metric K-factor measurement shown is when pressure is measured in bar. When pressure is measured in kPa, divide the metric K-factor shown by 10.0.
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Trigger and Support: Stainless Steel UNS-S31600
Fusible Element Assembly: Beryllium Nickel, coated with black acrylic paint.
Ordering Information: (Also refer to the current Viking price list.)
Order ESFR Pendent K16.8 Sprinkler VK503 by first adding the appropriate suffix for the sprinkler finish and then the appropriate
suffix for the temperature rating to sprinkler base part number.
Finish Suffix: Brass = A
Temperature Suffix: 165 °F (74 °C) = C, 205 °F (96 °C) = E
For example, sprinkler VK503 with a Brass finish and a 165 °F (74 °C) temperature rating = Part No. 14073AC.
Accessories: (Also refer to the Viking website.)
Sprinkler Wrench: Part No. 13635W/B (double-ended wrench - Use Side A. Side B is for use with K25.2 ESFR Pendent Sprinkler
VK510) Available since 2006.
Sprinkler Cabinet: Twelve-head capacity: Part No. 01725A (available since 1971)
ESFR PENDENT SPRINKLER
VK503 (K16.8)
4. INSTALLATION
WARNING
Viking sprinklers are manufactured and tested to meet rigid requirements of the approving agency. The sprinklers
are designed to be installed in accordance with recognized installation standards. System design must be based on
ESFR design guidelines described in the latest edition of Viking technical data, applicable FM Global Loss Prevention
Data Sheets, the latest NFPA Standards, the latest standards of Verband der Sachversicherer (VdS), Loss Prevention
Council (LPCB), the Authorities Having Jurisdiction, and also with the provisions of governmental codes, ordinances,
and standards whenever applicable. Deviation from the standards or any alteration to the sprinkler after it leaves the
factory including, but not limited to: painting, plating, coating, or modification, may render the sprinkler inoperative and
will automatically nullify the approval and any guarantee made by The Viking Corporation.
A. Sprinklers must be handled with care. They must be stored in a cool, dry place in their original shipping container. Never install
sprinklers that have been dropped or damaged in any way. Such sprinklers should be destroyed immediately.
NOTE: Wet pipe systems must be provided with adequate heat.
B. The sprinklers must be installed after the piping is in place to prevent mechanical damage. Before installing, be sure to have the
appropriate sprinkler model and style, with the correct orifice size, temperature rating, and response characteristics.
C. With the sprinkler contained in the plastic protective cap, apply a small amount of pipe-joint compound or tape to the male threads
only, while taking care not to allow a build-up of compound in the sprinkler orifice.
D. Use ONLY sprinkler wrench 13635W/B (shown in Figure 1) for installing ESFR Sprinkler VK503! With the sprinkler con-
tained in the protective cap, install the sprinkler onto the piping by applying the sprinkler wrench to the sprinkler wrench
flats only, while taking care not to damage the sprinkler operating parts.
DO NOT use any other type of wrench, as this could damage the unit.
DO NOT use the sprinkler deflector or fusible element to start or thread the sprinkler into a fitting.
DO NOT exceed 50 ft. lbs. of torque (hand tight, plus approximately two full turns with the wrench) to install these sprinklers. Higher
levels of torque may distort the sprinkler inlet with consequent leakage or impairment of the sprinkler.
E. After installation, the entire sprinkler system must be tested. The test must be conducted to comply with the Installation Standards.
Make sure the sprinkler has been properly tightened. If a thread leak occurs, normally the unit must be removed, new pipe-joint
compound or tape applied, and then reinstalled. This is due to the fact that when the joint seal is damaged, the sealing compound
or tape is washed out of the joint. Immediately replace any damaged units, using the special sprinkler wrench only.
F. After installation and testing and repairing of all leaks, remove the protective caps from the sprinklers. Do NOT use any
type of tool to remove the cap. Remove the cap by hand: turn it slightly and pull it off the sprinkler. When removing caps,
use care to prevent dislodging or damaging sprinkler ejector spring and fusible element. THE CAPS MUST BE REMOVED
FROM SPRINKLERS BEFORE PLACING THE SYSTEM IN SERVICE!
G. System design must be based on ESFR design guidelines described in applicable FM Global Loss Prevention Data Sheets, the
Form No. F_120106 18.10.11 Rev 18.2
Page 3
Page 3 of 6
TECHNICAL DATA
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
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latest standards of Verband der Sachversicherer, LPCB, the National Fire Protection Association, and the Authorities Having
Jurisdiction. All requirements of recognized sprinkler system design standards apply to systems utilizing Viking ESFR Pendent
Sprinklers.
ESFR PENDENT SPRINKLER
VK503 (K16.8)
5. OPERATION
During fire conditions, the heat-sensitive fusible element assembly disengages, releasing the seat and spring assemblies to open
the waterway. Water flowing through the sprinkler orifice strikes the sprinkler deflector, forming a uniform spray pattern to suppress
the fire.
6. INSPECTIONS, TESTS AND MAINTENANCE
NOTICE
The owner is responsible for maintaining the fire protection system and devices in proper operating condition. For
minimum maintenance and inspection requirements, refer to the NFPA standard that describes care and maintenance
of sprinkler systems. In addition, the Authorities Having Jurisdiction may have additional maintenance, testing, and
inspection requirements that must be followed.
A. The sprinklers must be inspected on a regular basis for corrosion, mechanical damage, obstructions, paint, etc. The frequency of
inspections may vary due to corrosive atmosphere, water supplies, and activity around the device.
B. Sprinklers that have been painted or mechanically damaged must be replaced immediately. Sprinklers showing signs of corrosion
shall be tested and/or replaced immediately as required. Installation standards require sprinklers to be tested and, if necessary,
replaced after a specified term of service. For Viking ESFR Pendent Sprinklers, refer to the Installation Standards (e.g., NFPA 25)
and the Authorities Having Jurisdiction for the specified period of time after which testing and/or replacement is required. Sprinklers
that have operated cannot be reassembled or reused, but must be replaced. When replacing sprinklers, use only new sprinklers.
C. The sprinkler discharge pattern is critical for proper fire protection. Therefore, nothing should be hung from, attached to, or other-
wise obstruct the discharge pattern. All obstructions must be immediately removed or, if necessary, additional sprinklers installed.
D. When replacing existing sprinklers, the system must be removed from service. Refer to the appropriate system description and/
or valve instructions. Prior to removing the system from service, notify all Authorities Having Jurisdiction. Consideration should be
given to employment of a fire patrol in the affected area.
1. Remove the system from service, drain all water, and relieve all pressure on the piping.
2. Using the special sprinkler wrench, remove the old sprinkler and install the new unit. Care must be taken to ensure that the replacement sprinkler is the proper model and style, with the correct orifice size, temperature rating, and response characteristics.
A fully stocked spare sprinkler cabinet should be provided for this purpose.
3. Place the system back in service and secure all valves. Check the replaced sprinklers and repair all leaks.
E. Sprinkler systems that have been subject to a fire must be returned to service as soon as possible. The entire system must
be inspected for damage and repaired or replaced as necessary. Sprinklers that have been exposed to corrosive products of
combustion, but have not operated, should be replaced. Refer to the Authorities Having Jurisdiction for minimum replacement
requirements.
7. AVAILABILITY
Viking ESFR K16.8 Pendent Sprinkler VK503 is available through a network of domestic and international distributors. See The
Viking Corporation web site for the closest distributor or contact The Viking Corporation.
8. GUARANTEE
For details of warranty, refer to Viking’s current list price schedule or contact Viking directly.
Form No. F_120106 18.10.11 Rev 18.2
Page 4
Page 4 of 6
TECHNICAL DATA
ESFR PENDENT SPRINKLER
VK503 (K16.8)
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Visit the Viking website for the latest edition of this technical data page: www.vikinggroupinc.com
TABLE 2
COMMODITY SELECTION AND DESIGN CRITERIA OVERVIEW FOR MODEL VK503 ESFR PENDENT SPRINKLERS
Storage TypeNFPAFM
Sprinkler TypeESFRStorage
Response TypeESFRQR
System TypeWet Pipe system onlyWet Pipe system only
Temperature Rating(s) ºF (ºC)165 ºF (74 ºC) and 205 (96 ºC)165 ºF (74 ºC) and 205 (96 ºC)
Open Frame Single, Double, Multiple-
Row, or Portable Rack Storage of Class I-IV
and Group A or B Plastics
Solid Pile or Palletized Storage of Class I-IV and
Group A or B Plastics
Refer to NFPA 13.Refer to FM 2-0 and 8-9.
Refer to NFPA 13.Refer to FM 2-0 and 8-9.
Idle Pallet StorageRefer to NFPA 13.Refer to FM 2-0, 8-9, and 8-24.
Rubber Tire StorageRefer to NFPA 13.Refer to FM 2-0 and 8-3.
Rolled Paper Storage (Refer to the standard.)Refer to NFPA 13.Refer to FM 8-21.
Flammable Liquid Storage (Refer to the standard.)Refer to NFPA 30.Refer to FM 7-29
Aerosol Storage (Refer to the standard.)Refer to NFPA 30BRefer to FM 7-31
Automotive Components in Portable Racks
(Control mode only, refer to the standard.)
Refer to NFPA 13.N/A
IMPORTANT: Always refer to Bulletin Form No. F_091699 - Care and Handling of Sprinklers. Viking ESFR Pendent Sprinklers
are to be installed in accordance with the latest edition of Viking technical data, the latest standards of NFPA, FM Global,
VdS, LPCB, and any other Authorities Having Jurisdiction, and also with provisions of governmental codes, ordinances, and
standards whenever applicable.