MICROFAST
®
QUICK
RESPONSE FUSIBLE
ELEMENT PENDENT
SPRINKLER VK353 (K8.0)
TECHNICAL DATA
Page 1 of 6
Form No. F_071814 19.02.21 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: [email protected]
Visit the Viking website for the latest edition of this technical data page www.vikinggroupinc.com.
1. DESCRIPTION
The Viking Microfast
®
Quick Response Fusible Element Pendent Sprinkler VK353
is a small, thermosensitive, solder link spray sprinkler available with various fin-
ishes and temperature ratings to meet design requirements. The special Polyester
and Polytetrafluoroethelyne (PTFE) coatings can be used in decorative applica-
tions where colors are desired.
2. LISTINGS AND APPROVALS
cULus Listed:
Category VNIV
FM Approved:
Class Series 2000
Refer to Approval Chart 1 and Design Criteria cULus Listing requirements, and
refer to Approval Chart 2 and Design Criteria for FM Approval requirements that
must be followed.
3. TECHNICAL DATA
Specifications:
Minimum Operating Pressure: 7 psi (0.5 bar)
Rated to 175 psi (12 bar) water working pressure
Factory tested hydrostatically to 500 psi (34.5 bar)
Thread size: 1/2” NPT, 15 mm BSP, 3/4” NPT, 20 mm BSP
Nominal K-Factor: 8.0 U.S. (115.2 metric**)
Overall Length: 2-5/16” (59 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: Brass UNS-C84400 or QM Brass
Deflector: Phosphor Bronze UNS-C51000 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 PTFE Coated Sprinklers: Belleville Spring-Exposed, Screw-Nickel Plated, Pip Cap-PTFE Coated
For Polyester Coated Sprinklers: Belleville Spring-Exposed
Ordering Information:
(Also refer to the current Viking price list.)
Order Viking Microfast
®
Quick Response Fusible Element Pendent Sprinkler VK353 by first adding the appropriate suffix for the
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 Black PTFE = N
Temperature Suffix: 165 °F (74 °C) = C, 205 °F (96 °C) = E, and 280 °F (138 °C)
For example, sprinkler VK353 with a 3/4” NPT thread, Brass finish and a 165 °F (74 °C) temperature rating = Part No. 18274AC
Available Finishes And Temperature Ratings:
Refer to Table 1.
Accessories:
(Also refer to the Viking website.)
Sprinkler Wrenches:
A. Standard Wrench: Part No. 21475MB (available since 2017).
B. Wrench for Recessed Pendent Sprinklers: Part No. 13655WB** (available since 2006)
C. Optional Protective Sprinkler Cap Remover/Escutcheon Installer Tool*** Part No. 15915 (available since 2010)
**A ½” ratchet is required (not available from Viking).
***Allows use from the floor by attaching a length of 1” diameter CPVC tubing to the tool. Ideal for sprinkler cabinets. Refer to Bulletin F_051808.
Sprinkler Cabinets:
A. Six-head capacity: Part No. 01724A (available since 1971)
B. Twelve-head capacity: Part No. 01725A (available since 1971)
Replaces Form No. F_071814 Rev 18.1.P65
(Removed F-1 Escutcheon.)
NOTE: As of May 2018 all logos have been removed from
the wrench boss.
