Viking VK503 K16.8 ESFR Pendent Sprinkler

Name: Viking VK503 K16.8 ESFR Pendent Sprinkler – Datasheet & Quote
Brand: Viking
SKU: VK503

A K16.8 ESFR head for ceilings that need more flow

The Viking VK503 sits between the K14 and K22.4 heads in the ESFR range. With a nominal K-factor of 16.8 (242 metric) it delivers more water at a given pressure than the VK500, which helps when the supply cannot easily reach the end-head pressure a K14 design would demand. Viking states it has been available since 2007. The sprinkler is fast response, fusible element and pendent, and a special deflector forms large droplets that can penetrate a developing high-challenge fire.

Typical use is warehouse and distribution storage on solid piles, pallets or open racks. The datasheet names Class I to IV commodities, cartoned and uncartoned unexpanded plastics and cartoned expanded plastics, and notes that some storage of rolled paper, aerosols and rubber tires can also be protected where the standards permit.

Technical specifications

Parameter	Specification
Manufacturer / model	Viking, VK503 ESFR pendent sprinkler
SIN	VK503
Nominal K-factor	16.8 US (242 metric, bar)
Thread size	3/4 in NPT or 20 mm BSPT
Maximum working pressure	175 psi (12 bar); factory test 500 psi (34.5 bar)
Overall length / deflector diameter	2-7/8 in (73 mm) / 1-3/4 in (44.5 mm)
Temperature ratings	165 °F (74 °C) suffix C, ceiling to 100 °F (38 °C); 205 °F (96 °C) suffix E, ceiling to 150 °F (66 °C)
Frame	Brass UNS-C84400; DZR brass for parts 27394XX and 27394XX-TQ
Sealing and trim	Nickel alloy Belleville spring with PTFE tape; copper and stainless steel seat; phosphor bronze deflector
Printed listings	cULus Listed VNWH (UL 199 rack storage with ceiling clearance of 20 ft or more); FM Approved Class 2027; China GB; CE CPR DOP_VK503
UL design limits	Ceiling to 45 ft (13.7 m), storage to 40 ft (12.2 m), 64 to 100 sq ft per sprinkler
System type	Wet pipe only

Base parts shown are 27394, 14073, 14818 and 20372 with brass finish; the “-TQ” suffix marks the InstaSeal protective cap.

How to read the part number

Viking asks the buyer to pick the base part number for thread and approval, then add finish and temperature suffixes. 27394AC is a VK503 in brass finish rated 165 °F, and 27394AE-TQ shows the 205 °F version with the InstaSeal cap. Because several base numbers differ only by thread standard or frame alloy, quote the exact thread (NPT or BSPT) and say whether DZR brass is required.

The UL design column asks for a deflector at least 36 in above the top of storage, spacing of 8 ft minimum and the stated 64 to 100 sq ft coverage. FM data is referred to FM 2-0 and FM 8-9.

Other Viking ESFR models

Compare K-factors across the family when the storage height or available pressure changes.

Viking ESFR model	K-factor and type	Connection
VK500	K14.0 ESFR pendent	3/4 in NPT or 20 mm BSPT
VK506	K22.4 ESFR pendent	1 in NPT or 25 mm BSPT
VK510	K25.2 ESFR pendent	1 in NPT or 25 mm BSPT
VK514	K28.0 ESFR pendent	1 in NPT or 25 mm BSPT
VK512	K25.2 ESFR dry pendent	1-1/2 in grooved

Before you request a price

Check that the project specification actually names the VK503 listing, since listings are model-specific and an ESFR head cannot simply be swapped for another K-factor without redoing the hydraulic design. Also confirm thread standard, finish, temperature rating, whether guards or water shields are needed, and the wet pipe system limitation. The attached Viking technical data contains all approval and design tables. See more Fire Fighting equipment and send us the full part number for a quotation.

Viking product ranges

Viking sprinklers run from standard and extended coverage heads to storage sprinklers such as the ESFR family, residential and dry barrel types. The valves and systems range includes wet pipe, dry pipe and deluge or preaction equipment, accelerators and flow control valves. Viking foam products include proportioners, discharge devices and high expansion foam generators, while Oxeo is its clean agent system.

Frequently Asked Questions