Fire and smoke control is a sequence problem before it is an equipment problem. The fan, damper, actuator, duct path and control signal must all move to the correct state at the correct point in the fire event.
Coordinate YONGFAN HTFC fire smoke-exhaust fan boxes (280 °C / 30 min, single/dual speed 1,400–171,000 m³/h), DTF in-line axial smoke fans, PYHL-14A jet-induction exhaust, FHF 70 °C fire isolation dampers, PFHF 280 °C smoke-exhaust fire dampers, PYF normally closed DC24V smoke valves, and 3C fire actuators.
Installing a standard 70 °C FHF fire damper in a dedicated smoke exhaust duct closes the extraction route early during a fire event.
Starting high-power smoke exhaust fans before PYF smoke valves confirm open position creates severe duct implosion shock.
Using oversized single-speed smoke fans for everyday low-speed ventilation wastes electrical energy and creates acoustic complaints.
Installing standard acoustic silencers with combustible internal packing inside high-temperature smoke-control ductwork.
Normally open fire dampers installed at fire-partition walls and floor slabs. Cuts off airflow and smoke migration when duct temperature reaches 70 °C. WS-FK features manual reset & 5-position adjustment; WSDc-FK adds DC24V electric closing; WSDj-FK adds motorized DC24V reset.
Normally open damper installed directly in dedicated smoke-exhaust ducts. Remains open during smoke extraction, allowing hot smoke to be evacuated. Closes automatically when smoke reaches 280 °C to isolate the path and protect downstream exhaust fans and shafts.
Normally closed smoke valves installed at smoke extraction points and wall outlets. Opens on a DC24V command from the fire alarm system to create the smoke evacuation path. Includes SDc-K standard electric, SDj-K motorized reset, SDc-YK remote reset, and SDc-YK-BS panel smoke outlets.
Double-inlet centrifugal fan box with external motor, rated for 280 °C / 30 min smoke duty (1,400–171,000 m³/h, 190–1,460 Pa, 56–106 dB(A)). HTFC-I provides dedicated single-speed smoke exhaust; HTFC-II provides dual-speed operation (low speed for daily ventilation, high speed for fire smoke exhaust).
In-line tube-axial fan engineered for direct duct mounting with documented 280 °C / 30 min fire smoke exhaust rating (1,886–114,829 m³/h, 115–2,266 Pa, Ø350–1600 mm, 0.5–45 kW). Provides compact straight-through airflow without large cabinet footprints.
Mixed-flow jet-induction fan documented with 280 °C / 30 min fire rating for ductless underground car park and tunnel smoke extraction. Induces high-velocity momentum to sweep smoke toward dedicated smoke shafts without complex duct networks.
Actuator assemblies certified to 3C / GB 15930-2007 standards for FHF, PFHF, and PYF dampers. Operating on DC 24 V (<0.7 A working current), providing integrated 70 °C / 280 °C sensor interfaces, position feedback microswitches, and manual or electric reset.
| Device | Normal Position | Primary Fire Action | Documented Trigger | Typical System Role |
|---|---|---|---|---|
| FHF Fire Damper | Normally OPEN | Closes to isolate HVAC duct | 70 °C fusible link / DC24V close | Fire-compartment boundary isolation |
| PFHF Smoke Damper | Normally OPEN | Stays open in smoke path, closes at high temp | 280 °C fusible link / DC24V close | High-temp shutdown in smoke-exhaust duct |
| PYF Smoke Valve | Normally CLOSED | Opens to create smoke-exhaust path | DC24V fire-control signal | Smoke outlet / extract-path opening |
| HTFC Fan Box | Standby / Low Speed | Starts / ramps to high speed for smoke extract | Fire alarm interlock / 280 °C / 30 min | Centrifugal smoke extraction & daily ventilation |
| DTF Axial Fan | Standby / Normal | Starts emergency smoke exhaust | Fire alarm command / 280 °C / 30 min | In-line vertical/horizontal shaft smoke exhaust |
| PYHL-14A Fan | Standby / Normal | Sweeps smoke toward extract shafts | Fire alarm command / 280 °C / 30 min | Ductless underground car park smoke induction |
Identify smoke zones, required emergency airflow (m³/h), and applicable fire design standard.
List FHF (70 °C), PFHF (280 °C), and PYF (DC24V) locations, rectangular W×H or circular ØD sizes.
Select HTFC-I/II or DTF fans rated for 280 °C / 30 min with fire-mode external static pressure.
Define fire alarm interlocks, position feedback verification, and manual/electric reset logic.
YONGFAN life-safety engineers will verify high-temperature fan performance points, check actuator power draw, match damper dimensions, and supply 3C / GB 15930 certificates.
HTFC and DTF fire-rated fans are tested at national fire inspection centers for continuous operation at 280 °C for 30 minutes.
FHF, PFHF, and PYF dampers are certified to GB 15930-2007 for blade closing reliability, leakage, and thermal release.
DC24V actuators undergo full stroke endurance testing, thermal sensor verification, and feedback microswitch checks.
Centrifugal smoke fan boxes are verified for aerodynamic performance, impeller balance, and motor temperature rise.
Both are normally open, but temperature action is different: FHF closes at 70 °C to isolate fire compartments; PFHF closes at 280 °C to protect smoke fans after smoke extraction.
PYF is a normally closed smoke-exhaust valve. It opens upon receiving a DC24V fire command to establish the smoke evacuation path and sends position feedback.
PFHF must remain open during smoke extraction so hot smoke (often 100–200 °C) can be safely evacuated without tripping the duct closed prematurely.
Documented HTFC fire-smoke configurations are certified for 280 °C for 30 minutes continuous operation under fire conditions.
HTFC-I is single-speed for dedicated smoke duty. HTFC-II is dual-speed (low speed for daily ventilation, high speed for emergency smoke exhaust).
Yes. YONGFAN documents fire-rated DTF builds certified for 280 °C / 30 min smoke-exhaust duty in straight in-line ducts.
Yes. Documented YONGFAN 3C fire-rated actuators operate on DC 24 V with <0.7 A working current and include feedback switches.
No. The PYF smoke-exhaust valve does not use a fusible thermal link; its primary defining action is opening on the DC24V electrical fire command.
No. Best practice requires the PYF smoke valve to return an open-position feedback signal before the smoke fan starts to prevent duct implosion.
Only if the silencer construction is certified for high-temperature smoke service without combustible packing, and its pressure drop is included in the fan ESP calculation.
Never install a 70 °C FHF fire damper in a smoke-exhaust path, and never omit 70 °C FHF isolation at compartment walls.
Standard comfort ventilation fans do not inherit 280 °C / 30 min ratings; ensure the exact ordered model code is fire-certified.
Example fire cause-and-effect sequences are illustrative; the project fire engineer and local jurisdictional fire code govern final logic.
Standard acoustic silencers must not be used in smoke ducts unless approved by fire authorities; include silencer pressure drop in fan sizing.
Send your smoke zone schedules, airflow rates, duct layout, and cause-and-effect matrix. YONGFAN life-safety engineers will verify high-temp fan curves, size dampers, and supply certified 3C submittal packages.
