The TYCO TY4851 is the upright model of the TY-B series, with a K 8.0 discharge coefficient and 1/2″ NPT thread, standard response and standard coverage, operated by a glass bulb 5 mm. It is designed for light, ordinary and extra-hazard occupancies such as banks, hotels, shopping malls, factories, refineries and chemical plants. Installed above the pipe with the deflector facing up. For where the sprinkler sits in the whole system, see the complete guide to sprinkler systems in Saudi Arabia.
In short
- Model (SIN): TY4851 — Upright.
- Discharge coefficient K 8.0, 1/2″ NPT connection.
- Glass bulb 5 mm, standard response.
- Temperature ratings in the datasheet: 57 / 68 / 79 / 93 / 141 / 182 °C.
- Maximum working pressure: 175 psi (12.1 bar).
- Series approvals: UL, C-UL, FM; LPCB / VdS for specific models. The approval of each model, finish and rating is in the approvals table of datasheet TFP151.
- This model combines a 1/2″ thread with a K-factor greater than 5.6; NFPA 13 prohibits this in new construction, so it is for retrofit in existing systems only.
How this sprinkler works
The glass bulb contains a fluid that expands when exposed to heat. When the rated temperature is reached, the fluid expands enough to shatter the bulb, the sprinkler opens and the deflector spreads the water over the fire area.
Installed above the pipe with the deflector facing up. Standard response is typically used for storage and industrial areas, per the project design.
Models in the series
| SIN | Orientation | K-factor | Thread |
|---|---|---|---|
| TY3151 | Upright | 5.6 | 1/2″ NPT |
| TY3251 | Pendent / Recessed Pendent | 5.6 | 1/2″ NPT |
| TY4151 | Upright | 8.0 | 3/4″ NPT |
| TY4251 | Pendent / Recessed Pendent | 8.0 | 3/4″ NPT |
| TY4851 — this model | Upright | 8.0 | 1/2″ NPT |
| TY4951 | Pendent | 8.0 | 1/2″ NPT |
Links to the other models are in the “Similar models” table below. The choice of model comes from the hydraulic calculation, hazard classification and installation method in the project design.
Application notes
- For in-rack use protected by solid shelves or horizontal barriers, the unshielded TY3151 / TY3251 / TY4151 / TY4251 are used; otherwise the intermediate-level versions in TFP351.
- Corrosion-resistant finishes are available per the datasheet for corrosive atmospheres; the datasheet notes that corrosion tests do not represent every possible atmosphere, so suitability for the actual environment should be checked.
Technical data
| Item | Value |
|---|---|
| Model (SIN) | TY4851 |
| Orientation | Upright |
| Discharge coefficient | K 8.0 gpm/psi½ (115.2 L/min/bar½) |
| Thread | 1/2″ NPT |
| Element and response | Glass bulb 5 mm — Standard Response |
| Coverage | Standard Coverage |
| Temperature ratings | 57 / 68 / 79 / 93 / 141 / 182 °C |
| Maximum working pressure | 175 psi (12.1 bar) |
| Installation torque | 7 – 14 lb-ft (9.5 – 19.0 N·m) |
| Wrench | W-Type 6 (W-Type 7 for recessed) |
| Escutcheon | Recessed pendent: Style 10 (1/2″) or Style 40 (3/4″) |
| Approvals | UL, C-UL, FM; LPCB / VdS for specific models |
| Datasheet | TYCO TFP151 |
The critical point: torque and the right wrench
Tighten only with the W-Type 6 wrench (W-Type 7 for recessed) on the wrench flats, never by the frame or deflector. Higher torque can distort the inlet.
Do not compensate for too little escutcheon adjustment by under- or over-tightening; readjust the sprinkler fitting instead.
Installation steps
- Inspect before installing: never install a sprinkler whose bulb is cracked or has lost liquid.
- Install the sprinkler in its correct orientation (Upright) as shown in the datasheet — never reversed.
- Apply pipe-thread sealant to the threads, then hand-tighten the sprinkler.
- Finish with the specified wrench (W-Type 6 (W-Type 7 for recessed)) within 7 – 14 lb-ft (9.5 – 19.0 N·m). Higher torque can distort the inlet and cause leakage.
Common mistakes
- Using this 1/2″ model with a K-factor above 5.6 in a new building; it is for retrofit only.
- Installing a sprinkler that was dropped, struck or slipped by the wrench. The datasheet requires any such sprinkler to be replaced.
- Painting or coating sprinklers on site. Sprinklers must not be altered after leaving the factory; altered sprinklers are replaced.
- Hanging objects from sprinklers, or cleaning them with anything other than a gentle feather duster.
Maintenance
Sprinklers that leak or show visible corrosion must be replaced, as must sprinklers exposed to corrosive products of combustion that cannot be fully cleaned. The owner is responsible for inspection, testing and maintenance to NFPA 25 and the authority having jurisdiction, preferably by a qualified inspection service. Before closing a main control valve for maintenance, obtain permission from the proper authorities and notify everyone affected.
Files and ordering
TYCO datasheet TFP151 and the available approval certificates are in the files section of this page. When ordering, state the model TY4851, temperature rating and finish, escutcheon. The datasheet lists the part numbers (P/N) for each combination.
How to order
Use the “Build your order” section on this page: add every model and quantity, then send the whole order by email or WhatsApp. It reaches us as a tidy PDF request sheet and we contact you with the quotation.
FAQ
What does TY4851 mean?
It is TYCO’s Sprinkler Identification Number (SIN). It identifies the exact model — orientation, K-factor and thread. The sprinkler is ordered by this number together with temperature rating and finish.
How do I choose the temperature rating?
From the highest expected ceiling temperature and the rating classes in the project’s governing standard, within the ratings available for this model in the datasheet.
Do all models in the series carry the same approvals?
Not always. The approvals table in datasheet TFP151 gives each model’s approvals by rating and finish, so check it when the project requires a specific approval.
References
- TYCO TFP151 — Series datasheet (attached)
- NFPA 13 — Standard for the Installation of Sprinkler Systems
- NFPA 25 — Inspection, Testing and Maintenance of Water-Based Fire Protection Systems
- TYCO TFP700 — Installer warning for handling and installing sprinklers
This page is general information to help with selection and ordering, taken from the attached TYCO datasheet. Final design is set by the project’s approved designer; the project specification, the consultant’s drawings and the latest datasheet revision govern.
