ESFR PENDENT SPRINKLER
VK503 (K16.8)
TECHNICAL DATA
Page 1 of 6
Form No. F_120106 19.11.15 Rev 19.1
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Telephone: 269-945-9501 Technical Services: 877-384-5464 Fax: 269-818-1680 Email: techsvcs@vikingcorp.com
Visit the Viking website for the latest edition of this technical data page: www.vikinggroupinc.com
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 per-
mits 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 the Approval Charts and Design Criteria on pages 3-5 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 ceil-
ing (20 ft or greater)
FM Approved:
Class 2027
NYC Approved:
MEA 89-92-E, Volume 41
China Approval:
Approved according to China GB Standard
Refer to Approval Chart 1 and Design Criteria on pages 3-4 for cULus Listing
requirements, and refer to Approval Chart 2 and Design Criteria on page 4 for
FM Approval requirements that must be followed.
3. TECHNICAL DATA
Specifications:
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 BSP
Nominal K-Factor: 16.8 U.S. (242 metric*)
* Metric K-factor measurement shown is when pressure is measured in bar. When pressure is meas-
ured in kPa, divide the metric K-factor shown by 10.0.
Overall Length: 2-7/8” (73 mm)
Deflector Diameter: 1-3/4” (44.5 mm)
Covered by one or more of the following patents: US5,829,532; US6,059,044; US6,336,509;
US6,502,643; US6,868,917; AU722593; GB2336777
Material Standards:
Frame Casting: Brass UNS-C84400
Deflector: Phosphor Bronze UNS-C51000
Seat and Insert Assembly: Copper UNS-C11000 and Stainless Steel UNS-S30400
Replaces Form No. F_120106 Rev 18.1.P65
(Revised China Approval; removed 19856.)
