TYCO Series RFII Royal Flush II Concealed Pendent Sprinklers – TY3531 and TY3551

The TYCO Series RFII “Royal Flush II” Concealed Pendent Sprinklers are decorative automatic fire sprinklers designed to provide standard-coverage fire protection while maintaining a clean architectural ceiling appearance.

This product page combines two models from the same sprinkler family:

• TY3531: 3 mm glass bulb, classified as Quick Response under UL, C-UL and NYC approvals.
• TY3551: 5 mm glass bulb, classified as Standard Response.

Both models share the same basic concealed construction, K-factor, installation arrangement, temperature options, cover-plate design and adjustment range. The main differences are bulb diameter, response classification and selected approvals.

The flat cover plate conceals the sprinkler above the finished ceiling, making the Series RFII suitable for architecturally sensitive locations such as hotels, office buildings, churches, restaurants and reception areas.

Key Features:

• Concealed pendent fire sprinkler.
• Series RFII “Royal Flush II”.
• Flat decorative cover plate.
• Standard coverage.
• Nominal K-factor of 5.6.
• Available in quick-response and standard-response versions.
• TY3531 with a 3 mm glass bulb.
• TY3551 with a 5 mm glass bulb.
• 1/2-inch NPT threaded connection.
• 1/2-inch vertical adjustment.
• Maximum working pressure up to 250 PSI under selected listings.
• Maximum 175 PSI under FM, VdS and LPCB approvals.
• Two available sprinkler temperature ratings.
• Multiple factory-applied cover-plate finishes.
• Two-piece sprinkler and cover-plate construction.
• Disposable protective cap for ceiling installation.
• Intended for automatic sprinkler systems designed to NFPA 13.
• Optional Air and Dust Seal for model TY3551.

Model Differences:

TY3531:

• Bulb diameter: 3 mm.
• Quick Response under UL, C-UL and NYC.
• UL Listed.
• C-UL Listed.
• NYC Approved – MEA 353-01-E.
• VdS Approved – Certificate G4090007.
• FM and LPCB classify this concealed sprinkler as Standard Response.

TY3551:

• Bulb diameter: 5 mm.
• Standard Response.
• UL Listed.
• C-UL Listed.
• FM Approved.
• LPCB Approved – Reference 094a/9.
• NYC Approved – MEA 353-01-E.
• Compatible with the optional listed Air and Dust Seal.

Operation:

Under normal conditions, the sprinkler is concealed above the ceiling behind the flat cover plate.

When exposed to heat from a fire:

• The three solder points securing the cover plate respond to heat.
• The cover plate releases and falls away.
• The deflector drops into its operating position along the guide pins.
• Heat continues to act on the glass bulb.
• The liquid inside the bulb expands.
• The bulb breaks at its rated temperature.
• The sealing assembly releases.
• Water begins to discharge.
• The deflector distributes water according to the standard-coverage spray pattern.

Discharge Coefficient:

• K-factor: 5.6 GPM/psi½.
• Metric K-factor: 80.6 LPM/bar½.

Connection:

• 1/2-inch NPT.
• ISO 7-1 connection available by ordering the appropriate version.

Maximum Working Pressure:

Under UL, C-UL and NYC:

• 250 PSI.
• 17.3 bar.

Under FM, VdS and LPCB:

• 175 PSI.
• 12.1 bar.

Available Temperature Ratings:

Option 1:

• Sprinkler temperature: 155°F.
• Metric temperature: 68°C.
• Cover plate temperature: 139°F.
• Metric cover-plate temperature: 59°C.

Option 2:

• Sprinkler temperature: 200°F.
• Metric temperature: 93°C.
• Cover plate temperature: 165°F.
• Metric cover-plate temperature: 74°C.

Adjustment:

• 1/2 inch.
• 12.7 mm.

Main Construction Materials:

• Frame: Bronze.
• Support cup: Plated steel.
• Guide pins: Stainless steel.
• Deflector: Bronze.
• Compression screw: Brass.
• Bulb: Glass.
• Cap: Bronze or copper.
• Sealing assembly: Beryllium nickel with PTFE.
• Cover plate: Brass.
• Retainer: Brass.
• Ejection spring: Stainless steel.

Available Cover-Plate Finishes:

• Grey White – RAL 9002.
• Brushed Brass.
• Brass.
• Pure White – RAL 9010.
• Signal White – RAL 9003.
• Jet Black – RAL 9005.
• Brushed Chrome.
• Chrome.
• Custom finish.

Two-Piece Assembly:

The product consists of:

• Sprinkler/Support Cup Assembly.
• Cover Plate/Retainer Assembly.

This construction provides several installation benefits:

• Allows sprinkler installation and pressure testing before ceiling completion.
• Allows ceiling finishing before installing the final cover plate.
• Permits access above suspended ceilings without removing the sprinkler.
• Provides 1/2-inch vertical adjustment.
• Protects the sprinkler during ceiling work using the disposable cap.

Optional Air and Dust Seal:

A silicone Air and Dust Seal is available for model TY3551.

It helps reduce the passage of air and dust from the space above the ceiling through the cover-plate area.

The seal is UL and C-UL Listed for use with the TY3551 Standard Response sprinkler.

Main Dimensions:

• Cover-plate diameter: 3.25 inches.
• Metric diameter: 82.6 mm.
• Cover-plate profile depth: 3/16 inch.
• Metric depth: 4.8 mm.
• Ceiling-clearance hole: 2.375 to 2.625 inches.
• Metric clearance hole: 60.3 to 66.7 mm.
• Fitting-face to ceiling distance: 1.75 to 2.25 inches.
• Metric installation depth: 44.5 to 57.2 mm.
• Nominal air gap: 3/32 inch.
• Metric air gap: 2.4 mm.

Installation Requirements:

• Install only in the pendent orientation.
• The sprinkler centerline must be perpendicular to the ceiling.
• Use only the specified RFII sprinkler wrench.
• Tightening torque must be between 7 and 14 lb-ft.
• Equivalent torque is 9.5 to 19 N·m.
• Do not correct elevation through over-tightening or under-tightening.
• Reposition the sprinkler fitting when required.
• Keep the disposable cap installed during ceiling work.
• The system is considered out of service while the cap remains installed.
• Remove the protective cap after ceiling completion.
• Confirm that the deflector moves freely before installing the cover plate.
• Do not install the cover plate in a manner that lifts the ceiling panel.

Important Precautions:

• Use only factory-finished Series RFII cover plates.
• Do not field paint the sprinkler or cover plate.
• Do not use the sprinkler where air pressure above the ceiling exceeds pressure below the ceiling.
• Downward airflow through the support cup can delay operation.
• Maintain the required nominal air gap.
• Do not seal the air gap with ceiling paint.
• Replace sprinklers showing leakage or corrosion.
• Replace sprinklers damaged during handling or installation.
• Do not reinstall a removed sprinkler.
• Replace a dislodged cover plate immediately.

Applications:

• Hotel lobbies.
• Hotels and resorts.
• Office buildings.
• Restaurants.
• Churches and places of worship.
• Shopping malls.
• Reception areas.
• Conference rooms.
• Offices.
• Architecturally sensitive ceilings.
• Projects requiring concealed decorative sprinklers.

Standards and Approvals Shown:

• UL Listed.
• C-UL Listed.
• FM Approved according to model and response classification.
• LPCB Approved.
• VdS Approved for TY3531.
• NYC Approved.
• NFPA 13.
• CEA 4001 under VdS design criteria.
• NFPA 25 for inspection, testing and maintenance.

Important Note:

Models TY3531 and TY3551 are combined under one product because they use the same Royal Flush II construction and product appearance. Their primary differences are bulb size, response classification and selected approvals.

The final model, temperature rating and finish must be selected according to hydraulic calculations, occupancy classification, project specifications, consultant requirements and the authority having jurisdiction.