Viking XT1 Concealed Pendent Fire Sprinkler | VK4921 | Standard Response | 5.6K | 175F | 23114AD

Viking XT1 VK4921 Standard Response Concealed Pendent Fire Sprinkler activates at 175F (79C) to defend up to ordinary hazard commercial occupancies against fire. This UL and FM-approved fire sprinkler features a 5.6K orifice and a 1/2 in. (12.7 mm) NPT connection. The model replaces Viking model number 20034AD.

Viking XT1 VK4921 Concealed Pendent Fire Sprinkler is a Standard Response sprinkler that delivers decorative, competitively-priced defense against fire in up to ordinary hazard Group II commercial occupancies such as universities, auditoriums, churches, and parking garages. Using a heat-activated 3mm glass bulb, this automatic fire sprinkler opens when ambient temperatures reach 175F (79C), reducing the likelihood of flashover and facilitating safe evacuation.

The Viking Model VK4921 has a 5.6 K-Factor and installs with 1/2 in. (12.7 mm) National Pipe Thread (NPT), used in fire sprinkler systems throughout the United States. This fire sprinkler features a brass body, copper deflector, and nickel-alloy sealing assembly with PFTE tape.

This 175F (79C) temperature rating is ideal for situations where 155F is not a high enough temperature, such as areas near a furnace or in an attic.  Fire Sprinklers can be installed to wet and dry pipe fire sprinkler systems, and are preferred for use in one and two-family dwellings, apartments, duplexes, and boarding houses. The Viking VK4921 is also a suitable choice for installation in many college dormitories, condominiums, and nursing homes.

This sprinkler is approved for a maximum working pressure of 250 PSI (17.2 BAR) by Underwriters Laboratory and 175 PSI (12 BAR) by Factory Mutual (FM). See data sheet for details. This pendent sprinkler hangs from above-ceiling piping and may be installed and used in accordance with NFPA 13 and local fire code. Each Model VK4921 sprinkler is made by Viking, a global leader in fire protection manufacturing for nearly 100 years.

This product is UL and FM approved, and appropriate for use in fire protection systems when accepted by the authority having jurisdiction. In accordance with NFPA 13, a higher temperature rating may be required when installing a quick response fire sprinkler in or near heat sources, unventilated spaces, uncovered steam mains, or uninsulated rooftops. Concealed pendent sprinklers should not be installed where the air pressure above the ceiling is greater than the pressure below, which may prevent or delay sprinkler activation in the event of a fire.

Technical Documents

Click here to view the datasheet for the Viking VK4921 Quick Response Concealed Pendent Fire Sprinkler.