After the 280°C smoke exhaust fire damper fuses and closes, the signal is not fed back to the fire control room, so the damper status cannot be determined during a fire.
Smoke exhaust fire dampers are critical safety devices in smoke control and exhaust systems, and the 280°C fusible-link closure function is the last line of defense for fire compartmentation. Section 6.4 of GB 51251-2017 specifies requirements for the selection and installation of smoke exhaust fire dampers. GB 15930-2007 "Fire Dampers for Building Ventilation and Smoke Exhaust Systems" is the dedicated product standard for smoke exhaust fire dampers. Their fusing temperature is accurately controlled at 280°C ± 3°C.
The technical parameters of smoke exhaust fire dampers include a closing time of no more than 5 seconds, an air leakage rate of no more than 700 m³/h per square meter at a pressure differential of 300 Pa, and a fire resistance rating of no less than 1.5 hours. The valve body material is cold-rolled galvanized steel sheet with a thickness of no less than 1.5 mm. The reset method is manual reset. The fusible link of the temperature-controlled release device must be replaced after exceeding its 3-year validity period to prevent failure due to aging.
Installation locations include the main duct at the smoke exhaust fan inlet, where smoke exhaust ducts penetrate fire compartment partition walls, where they penetrate floor slabs, where they penetrate machine room partition walls, and where smoke exhaust branch ducts connect to each smoke control zone. A smoke exhaust fire damper must be installed on the main duct at the smoke exhaust fan inlet — this is the most critical installation point. Smoke exhaust fire dampers must also be installed on main smoke exhaust ducts shared by multiple smoke control zones.
Installation key points are as follows: the valve body orientation must align with the airflow direction; a maintenance clearance of no less than 200 mm must be provided around the valve; fire dampers with a diameter or side length of no less than 630 mm must be provided with independent supports and hangers; the valve closure signal must be connected to the fire alarm system; fire dampers installed within suspended ceilings must be provided with access openings of no less than 400 × 400 mm. The distance between the smoke exhaust fire damper and the smoke exhaust fan should not exceed 5 m.
Common problems include fusible link failure due to storage exceeding 3 years and aging of the thermal element, blade seizure due to corroded shafts or deformed blades, failure of signal feedback due to damaged limit switches or loose wiring, incorrect installation orientation affecting closing tightness, and incomplete reset affecting smoke exhaust volume. Monthly visual inspections should check for corrosion, deformation, and blockage. Quarterly manual open and close tests should verify blade movement flexibility. Semi-annual inspections of the temperature-controlled release device should be conducted, with replacement if older than 3 years.
The role of smoke exhaust fire dampers in hotel smoke control and exhaust systems is irreplaceable. Smoke exhaust fire dampers installed on smoke exhaust ducts in large-space areas such as hotel corridors, ballrooms, and conference rooms must be manually tested one by one during annual fire inspections, with their actuation status and signal feedback recorded. The limit switch wiring of the valves should be secure and reliable, and the module addresses should be correct. The access opening locations for smoke exhaust fire dampers within suspended ceilings should be clearly marked on as-built drawings so that maintenance personnel can quickly locate and operate them. For smoke exhaust ducts in hotel guest room areas, the installation of fire dampers should avoid affecting the sound insulation performance of guest rooms; after installation of fire dampers where ducts penetrate fire walls, gaps should be sealed with non-combustible materials. Routine inspections of smoke exhaust fire dampers should include checking whether the valve body is obstructed by decorative finishes, whether the manual reset handle operates flexibly, and whether the signal feedback status is consistent with the controller display. Any abnormality found should be promptly scheduled for repair or replacement to ensure reliable actuation of the system in a fire.
Maintenance management of smoke exhaust fire dampers also requires attention to the electrical wiring and module configuration of the valves. Each smoke exhaust fire damper should be provided with an independent input/output module, and the module address should be consistent with the design drawings. The open/closed status signal of the valve should be transmitted via the module to the graphic display device in the fire control room. The wiring terminals of the limit switch should be securely fastened to prevent loosening due to vibration. The power supply wiring of the valve should use fire-resistant cables installed in metal conduits. Quarterly testing of smoke exhaust fire dampers should be documented, including test date, test personnel, valve actuation status, signal feedback status, and existing problems. If a valve is found to actuate inflexibly or signal feedback is abnormal, repair or replacement should be arranged immediately. Replacement smoke exhaust fire dampers should be of the same model and specifications as the original valves, and functional testing should be re-performed after installation. The fusible link of the temperature-controlled release device should be inspected every six months, and those approaching the 3-year validity period should be replaced before expiration. The blade closing tightness of the valve should be inspected annually, and those with excessive air leakage should have blade positions adjusted or sealing strips replaced. Through standardized maintenance management, smoke exhaust fire dampers are ensured to close reliably in a fire and feed back accurate status signals, providing an accurate decision-making basis for the fire control room.
Maintenance management of smoke exhaust fire dampers also requires attention to the electrical wiring and module configuration of the valves. Each smoke exhaust fire damper should be provided with an independent input/output module, and the module address should be consistent with the design drawings. The open/closed status signal of the valve should be transmitted via the module to the graphic display device in the fire control room. The wiring terminals of the limit switch should be securely fastened to prevent loosening due to vibration. The power supply wiring of the valve should use fire-resistant cables installed in metal conduits. Quarterly testing of smoke exhaust fire dampers should be documented, including test date, test personnel, valve actuation status, signal feedback status, and existing problems. If a valve is found to actuate inflexibly or signal feedback is abnormal, repair or replacement should be arranged immediately. Replacement smoke exhaust fire dampers should be of the same model and specifications as the original valves, and functional testing should be re-performed after installation. The fusible link of the temperature-controlled release device should be inspected every six months, and those approaching the 3-year validity period should be replaced before expiration. The blade closing tightness of the valve should be inspected annually, and those with excessive air leakage should have blade positions adjusted or sealing strips replaced. Through standardized maintenance management, smoke exhaust fire dampers are ensured to close reliably in a fire and feed back accurate status signals, providing an accurate decision-making basis for the fire control room. The installation acceptance of smoke exhaust fire dampers is an important part of the acceptance of smoke control and exhaust system works. During acceptance, each valve should be checked one by one to verify whether its model, specifications, installation location, and actuation direction comply with the design requirements. The manual actuator should be used to open and close the valve to check blade movement flexibility and closing tightness. Simulated signals should be used to test the electric closing function and signal feedback function of the valve, confirming that the limit switch trigger position is accurate and signal feedback is normal. The installation integrity and validity period of the temperature-controlled release device should be checked. Whether the access openings of the valves are reasonably located and sized to meet maintenance needs should be checked. Acceptance records should include the inspection results and confirmation signatures for each valve, and only after passing can system linkage acceptance proceed. The maintenance file of smoke exhaust fire dampers should include the installation location, model and specifications, maintenance and test records, and replacement records of each valve. The information in the maintenance file should be consistent with the valve information in the graphic display device of the fire control room, facilitating quick lookup and operation by maintenance personnel. For new construction projects, a complete initial maintenance file for smoke exhaust fire dampers should be established after completion acceptance, and for renovation projects, the maintenance file should be updated promptly.
The installation acceptance of smoke exhaust fire dampers is an important part of the acceptance of the smoke control and exhaust system. During acceptance, each damper should be checked one by one to verify whether its model, specifications, installation position and operating direction meet the design requirements. Operate the manual actuator to open and close the damper and check the flexibility of blade movement and the tightness of closure. Use simulated signals to test the electric closing function and signal feedback function of the damper, and confirm that the trigger position of the limit switch is accurate and the signal feedback is normal. Check the installation integrity and validity period of the temperature-controlled release device. Check whether the inspection opening of the damper is reasonably located and sized to meet maintenance needs. The maintenance file of smoke exhaust fire dampers should include the installation position, model and specifications, maintenance and test records, and replacement records of each damper. The information in the maintenance file should be consistent with the damper information in the graphic display device of the fire control room. Emergency fault handling of smoke exhaust fire dampers is an important part of ensuring system functionality. When a smoke exhaust fire damper fails, maintenance personnel should handle it by category according to the fault symptoms. For abnormal signal feedback, first check the fixing and wiring of the limit switch. For seized blades, first check whether the rotating shaft is corroded and whether the blades are deformed. For faults of the electric actuator, first check whether the power supply is normal and whether the wiring is secure. For a detached fusible link, check whether the actuation temperature was reached, whether it was a false operation, or whether it failed due to aging. When a smoke exhaust fire damper fails, the smoke control and exhaust system may not operate normally; therefore, fault troubleshooting should be given priority to restore system functionality as soon as possible. Emergency spare parts for smoke exhaust fire dampers should include at least one set each of the limit switch, actuator and fusible link for each model, ensuring that faults can be quickly repaired by replacement to restore system functionality. Through timely emergency fault handling, the functional integrity of the smoke control and exhaust system is ensured.
Emergency fault handling of smoke exhaust fire dampers is an important part of ensuring system functionality. When a smoke exhaust fire damper fails, maintenance personnel should handle it by category according to the fault symptoms. For abnormal signal feedback, first check the fixing and wiring of the limit switch and use a multimeter to measure the on/off state of the contacts. For seized blades, first check whether the rotating shaft is corroded and whether the blades are deformed; remove rust and lubricate if corroded, and adjust or replace the blades if deformed. For faults of the electric actuator, first check whether the power supply is normal and whether the wiring is secure. For a detached fusible link, check whether the actuation temperature was reached, whether it was a false operation, or whether it failed due to aging, and replace the fusible link after confirming the cause. Emergency spare parts for smoke exhaust fire dampers should include at least one set each of the limit switch, actuator and fusible link for each model, ensuring that faults can be quickly repaired by replacement to restore system functionality. The annual inspection of smoke exhaust fire dampers should include manual testing of the operating status and signal feedback of each damper one by one. Through timely emergency fault handling and regular inspection, it is ensured that smoke exhaust fire dampers can reliably close and feed back accurate status signals in a fire.
The maintenance management of smoke exhaust fire dampers requires the establishment of a complete filing system and testing plan. The installation position, model and specifications, maintenance and test records, and replacement records of each damper should be archived and retained. Quarterly testing and annual inspection of dampers should be developed into standardized operating procedures and performed by trained professionals. Emergency spare parts for smoke exhaust fire dampers should be stocked on site to ensure rapid replacement in the event of a fault. The full life cycle management of smoke exhaust fire dampers includes stages such as selection and design, installation and construction, acceptance and commissioning, operation and maintenance, and replacement. By establishing damper health records and regular performance evaluation, it is ensured that the system can operate reliably in a fire. The reliable operation of smoke exhaust fire dampers is an important part of ensuring building fire safety and must be given high priority.