Viking MICROFAST VK301 Technical Data Manual

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
The Viking Microfast
®
is a small, thermosensitive, solder link spray sprinkler available in several differ-
ent finishes and temperature ratings to meet design requirements. The special
Polyester and Electroless Nickel PTFE (ENT) coatings can be used in decorative
applications where colors are desired. In addition, the ENT coating has been
investigated for installation in corrosive environments and is listed/approved as
indicated in the approval charts.
2. LISTINGS AND APPROVALS
cULus Listed: Category VNIV
FM Approved: Classes 2002 and 2020
China Approval: Approved according to China GB standard

NOTE: Other International approval certificates are available upon request.
Refer to Approval Charts and Design Criteria for listing and approval requirements
that must be followed.
3. TECHNICAL DATA
Specifications:
Minimum Operating Pressure: 7 psi (0.5 bar)*
Maximum Working Pressure: 175 psi (12 bar) wwp.
Factory tested hydrostatically to 500 psi (34.5 bar)
Testing: U.S.A. Patent No. 4,831,870
Thread size: 1/2" NPT, 15 mm BSPT
Nominal K-factor: 5.6 U.S. (80.6 metric**)
Overall Length: 2-1/4" (58 mm)
*cULus Listing, FM Approval, and NFPA 13 installs require a minimum of 7 psi (0.5 bar). The
minimum operating pressure for LPCB and CE Approvals ONLY is 5 psi (0.35 bar).
Material Standards:
Frame Casting: QM Brass
Deflector: Brass UNS-C23000 or Copper UNS-C19500
Fusible Element Assembly: Nickel Alloy
Trigger and Support: Stainless Steel UNS-S31600
Belleville Spring Sealing Assembly: Nickel Alloy, coated on both sides with PTFE Tape
Seat and Insert Assembly: Copper UNS-C11000 and Stainless Steel UNS-S30400
Screw: Brass UNS-C36000
For Polyester Coated Sprinklers: Belleville Spring-Exposed
For ENT Coated Sprinklers: Belleville Spring-Exposed, Screw and Pip Cap-ENT Coated
Ordering Information:
Order Viking Microfast
sprinkler finish and then the appropriate suffix for the temperature rating to the sprinkler base part number.
Finish Suffix: Brass = A, Chrome = F, White Polyester = M-/W, Black Polyester = M-/B, and ENT = JN
Temperature Suffix: 165 °F (74 °C) = C, 205 °F (96 °C) = E, and 280 °F (138 °C) = G
For example, sprinkler VK301 with a 1/2" NPT thread, Brass finish and a 165 °F (74 °C) temperature rating = Part No. 17535AC
Available Finishes And Temperature Ratings: Refer to Table 1.
Accessories: (Also refer to the Viking website.)
Sprinkler Wrench: Standard Wrench: Part No. 21475M/B (available since 2017)
Sprinkler Cabinets:
A. Six-head capacity: Part No. 01724A (available since 1971)
B. Twelve-head capacity: Part No. 01725A (available since 1971)
Form No. F_062414 Rev 01
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Quick Response Upright Fusible Element Sprinkler VK301
(Also refer to the current Viking price list.)
Quick Response Fusible Element Upright Sprinkler VK301 by first adding the appropriate suffix for the
®
June 20, 2022
TECHNICAL DATA
MICROFAST QUICK
®
RESPONSE FUSIBLE
ELEMENT UPRIGHT
SPRINKLER VK301 (K5.6)
Replaces Form No. F_062414 Rev 20.1
(Added part number.)
Page 1 of 4