Reliable F1FR56 K5.6 Quick Response Sprinkler

The Reliable F1FR56 series is a range of standard coverage, quick-response, standard spray automatic sprinklers with a nominal K-factor of 5.6 (80 metric) and a sensitive 3.0 mm glass bulb. Bulletin 074 (June 2025) lists upright, intermediate upright, pendent, recessed and concealed pendent, horizontal sidewall and vertical sidewall versions with a low-profile, compact design and a wide choice of finishes, making it a general-purpose sprinkler for light and ordinary hazard occupancies.

Configurations and identification

Each orientation carries its own sprinkler identification number (SIN) and its own approval set. The upright and pendent versions are the broadest: cULus, FM, LPCB, VdS, EC, WM and UKCA are printed for them, with a maximum working pressure of 175 psi (12 bar), or 250 psi (17 bar) for cULus only. Horizontal sidewall is cULus and FM, and vertical sidewall is cULus, FM and LPCB. With a listed water shield, the upright and pendent sprinklers can serve as intermediate sprinklers in racks and below grated walkways.

Key features from the bulletin

• 3 mm glass bulb in five temperature ratings: 135, 155, 175, 200 and 286 F (57, 68, 79, 93 and 141 C).
• Brass alloy frame and deflector, bronze cap, nickel with PTFE sealing washer, copper alloy load screw.
• Threads 1/2 in NPT or ISO 7-R1/2.
• Corrosion-resistant electroless nickel PTFE finish, cULus Listed and FM Approved as corrosion resistant.

Technical specifications

Data from Bulletin 074 Table A and the product tables.

Finishes and ordering

Standard finishes are bronze, brass, chrome, white polyester and white paint on escutcheons; special finishes include electroless nickel PTFE, bright brass, satin chrome and custom colours. Paint or coatings applied over the factory finish void approvals and warranties. When ordering, state orientation, temperature rating, sprinkler finish, escutcheon finish and cover plate finish, and the wrench. The 286 F (141 C) rating is not listed for recessed or concealed use, and the vertical sidewall is listed for light hazard only.

Installation and maintenance notes

Install to NFPA 13 with the Reliable wrench named in the bulletin; exceeding the recommended torque may cause leakage or damage. Leave orange bulb protectors in place until the system is in service, then remove them by hand. Keep sprinklers in their original packaging until installation, do not clean them with soap, ammonia or similar liquids, replace any painted sprinkler, and keep a stock of spares per NFPA 25. For concealed CCP installations, keep the space above the ceiling at positive pressure relative to the room, as the bulletin states.

Typical applications

Quick-response K5.6 sprinklers are used in offices, hotels, hospitals, schools and retail spaces, where the bulb operates quickly to protect occupants. Recessed or concealed versions suit finished ceilings. Confirm hazard class, spacing and approvals with your designer.

Selection and installation notes

Sprinklers, nozzles and valves are chosen by the system designer from the hazard classification, the coverage, the K-factor, the temperature rating and the pressure the water supply can deliver, and the system must be designed, installed and commissioned by qualified people to the standard and authority rules that apply to the project. Confirm the finish, the orientation, the response type and the temperature rating against the design, use only the wrench the maker specifies, never paint, coat or bend a sprinkler and keep spare sprinklers and a wrench in the cabinet as the rules require. Check the listings and approvals required for the project with the authority before purchase.

Keep a record of the sprinkler type and rating at each location, and protect the units from damage during building work.

Information needed for a quotation

Send the full model code, the quantity, the delivery location in Oman or the GCC, the intended use and any accessories needed, so that the complete package can be quoted together.

Documents and supply information

The manufacturer data sheet is attached to this page and should be read together with the project specification and the site risk assessment before a purchase is confirmed. Ratings, standards and dimensions are quoted as printed on that sheet. Lead time, stock position and certificates available with the shipment are confirmed in the quotation, and we supply to Oman and the wider GCC region for industrial, utility and building services projects.

Related items and documents

The bulletin refers to Reliable escutcheons (Technical Bulletin 204) and the F1FR80 series for K8.0 duty. The bulletin is hosted on this page. Seven Star LLC is an independent supplier in Muscat; see the Fire Fighting range or send orientation, temperature rating and finish for a quotation.

Frequently asked questions

What is the K-factor of the F1FR56?

Nominal K-factor 5.6 (80 metric).

Which temperature ratings are available?

135, 155, 175, 200 and 286 F (57, 68, 79, 93 and 141 C).

What is the maximum working pressure?

175 psi (12 bar), or 250 psi (17 bar) for cULus on upright and pendent versions.

Which orientations does the series include?

Upright, intermediate upright, pendent, recessed and concealed pendent, horizontal sidewall and vertical sidewall.

Can I paint the sprinkler?

No. The bulletin says paint or other coatings applied over the factory finish void all approvals and warranties.