Pyro-Chem Kitchen Knight II 2F Nozzle - 553328

The Pyro-Chem 2F Nozzle (Part No. 553328) is the high-volume tip of the Kitchen Knight II wet chemical suppression series. In the sophisticated math of fire safety design, the nozzle is the final arbiter of success; while the cylinder stores the agent, the 2F is responsible for the actual delivery. As a 2-flow rated component, this nozzle delivers double the volume of a standard discharge point, making it the primary specified choice for protecting high-hazard appliances like full-sized deep-fat fryers and high-BTU griddles.

Operating on the principle of hydraulic flow-point balancing, the 553328 ensures that the system's energy budget is distributed effectively across extensive cooking surfaces. When triggered, the nozzle atomizes potassium acetate to initiate saponification, creating a thick soap blanket that excludes oxygen and traps flammable vapors. Its wide-angle kinetic knockdown pattern is specifically calibrated to provide a soft landing for the agent, securing the hazard without causing dangerous oil splash-back. Each nozzle features a metal blow-off cap defense to prevent grease-loading, ensuring a zero-failure discharge when it matters most.

The 553328 must be installed by a licensed fire suppression technician in strict accordance with the Kitchen Knight II design manual and the system's as-built drawings. Because the 2F nozzle consumes 2.0 flow points, the total flow point count of all nozzles in the system must not exceed the rated capacity of the agent tank. Nozzle placement must conform to the specific Nozzle Aiming Point (NAP) for each protected appliance as defined in the KKII manual.

The included metal blow-off cap (550607) and retaining ring must be installed on every 553328 nozzle to protect the precision-machined orifice from grease loading between service intervals. During each semi-annual inspection, technicians must verify the cap is present, moves freely, and that the orifice is free of blockage. Any nozzle showing signs of corrosion, heat distortion, or orifice restriction must be replaced with a new OEM 553328 to maintain the system's UL 300 listing.

How do I determine if a hazard requires a 1-flow or 2-flow nozzle?

The choice is dictated by the hazard dimensions of your appliance. While a standard 18-inch fryer may only require a 1-flow unit, larger industrial fryers or multiple-basket units mandate the 553328 to achieve total surface coverage and prevent dry spots in the foam blanket.

Can I use the 553328 in an Ansul R-102 system?

No. While both brands are owned by Johnson Controls, the 553328 is specifically listed for Pyro-Chem hardware. The atomization patterns are tuned for the specific viscosity of the Pyro-Chem agent; mixing brands is a code violation that will void your UL listing and insurance coverage.