Dampers are an important part of any HVAC system, but they can also be a potential fire hazard if not maintained. To prevent fires in dampers, regular maintenance and cleaning are essential. Fire and smoke dampers can also be installed to prevent the spread of flames and smoke within a building. By following these tips, building owners and managers can ensure the safety of their HVAC systems and prevent fires from starting in dampers.

How dampers work

Dampers are a vital component of any heating, ventilation, and air conditioning (HVAC) system. They are designed to control the flow of air within a building, allowing for temperature regulation and air quality control. However, dampers can also be a potential fire hazard if not maintained properly.

How fires start in dampers

Dampers are typically made of metal and can become coated with dust, dirt, and other debris over time. This buildup can accumulate on the damper blades, creating a fuel source for a fire. Additionally, dampers can become damaged over time due to corrosion or wear and tear, which can create gaps between the blades. These gaps can allow flames and hot gases to escape, potentially starting a fire.

Another way fires can start in dampers is through the accumulation of grease. This is particularly true for kitchen exhaust dampers, which are used to remove smoke and cooking fumes from commercial kitchens. Over time, grease can build up on the damper blades and surrounding ductwork, creating a fuel source for a fire.

Preventing fires in dampers

Preventing fires in dampers requires regular maintenance and cleaning. Here are some tips for preventing fires in dampers:

  1. Schedule regular inspections: Dampers should be inspected at least once a year by a qualified HVAC technician. During the inspection, the technician will check for signs of corrosion, damage, and buildup.
  2. Clean dampers regularly: Dampers should be cleaned regularly to remove any debris, dust, or grease buildup. This can be done using a soft brush or vacuum. Kitchen exhaust dampers may require more frequent cleaning due to the accumulation of grease.
  3. Install fire and smoke dampers: Fire and smoke dampers are designed to prevent the spread of flames and smoke within a building. They are installed in ductwork and are activated by a smoke or fire detection system. These dampers can help prevent fires from spreading through HVAC systems.
  4. Maintain proper airflow: Dampers should be set to allow for proper airflow within the building. If the airflow is restricted, the HVAC system may not be able to function properly, potentially leading to overheating and fires.
  5. Use proper materials: When installing dampers, it is important to use materials that are fire-resistant and comply with local building codes. This can help prevent fires from starting in the first place.

Types of Dampers

It’s also helpful to understand the type of damper in your facility. There are several types of dampers, each designed for a specific purpose. Here are some of the most common types of dampers:

  1. Volume Control Dampers (VCDs) Volume Control Dampers are the most basic type of damper used to regulate the airflow rate in ducts. They can be manually adjusted to increase or decrease the airflow in specific zones or rooms of a building. They are typically made of galvanized steel, aluminum, or PVC.
  2. Fire and Smoke Dampers (FSDs) Fire and Smoke Dampers are designed to prevent the spread of flames and smoke through HVAC ducts. They are typically installed at duct penetrations through fire-rated walls and floors. FSDs are activated by a fire detection system and close automatically to prevent fire and smoke from spreading to other areas of a building.
  3. Backdraft Dampers Backdraft Dampers are designed to prevent the backflow of air or gas into an HVAC system. They are commonly used in kitchen and bathroom exhaust systems, where negative pressure can cause air to flow back into the building. Backdraft dampers are typically spring-loaded and open automatically when the airflow direction changes.
  4. Pressure Relief Dampers (PRDs) Pressure Relief Dampers are used to regulate the pressure in an HVAC system. They are typically installed in areas where there is a potential for high pressure, such as near fans or blowers. PRDs can be set to open automatically when the pressure exceeds a certain level, allowing excess air or gas to escape.
  5. Balancing Dampers Balancing Dampers are used to equalize the airflow in an HVAC system. They are typically installed in duct branches or junctions and can be manually adjusted to balance the airflow between different zones or rooms. Balancing dampers are typically made of galvanized steel or aluminum.
  6. Motorized Dampers Motorized Dampers are similar to Volume Control Dampers but are equipped with a motor that allows for remote control. They are typically used in larger HVAC systems where manual adjustment would be impractical. Motorized dampers can be operated through a building automation system or remote control panel.
  7. Smoke Extract Dampers Smoke Extract Dampers are designed to extract smoke from a building in the event of a fire. They are typically installed at high points in a building and can be activated manually or automatically in the event of a fire. Smoke extract dampers are typically made of galvanized steel or aluminum.

There are various types of dampers designed for specific purposes. Choosing the appropriate type of damper for a specific application can help ensure optimal HVAC system performance and improve the safety of building occupants.

NFPA fire codes and damper safety

The National Fire Protection Association (NFPA) has several codes and standards related to dampers, depending on the type of damper and its application. Some of these fire codes related to damper safety include NFPA 90, NFPA 92A, NFPA 105, NFPA 80, and NFPA Life Safety Code 101.

It is important to note that the NFPA codes and standards related to dampers are regularly updated and revised. It is essential to consult the most current version of these codes and standards when designing, installing, or maintaining dampers in HVAC systems.

Fire Systems, Inc.

Work with a professional fire protection company to ensure the safety of your entire building, including the HVAC system. A trained technician knows what to look for when inspecting and maintaining your HVAC system. Be sure a highly skilled and licensed HVAC company installs your system. Your buildings’ HVAC system can become a serious fire hazard if not well maintained. Fire Systems, Inc. can help you design a fire protection plan that will protect all aspects of your facility, including the HVAC system and dampers. Call us today at 770-333-7979 or visit our website for more information on all of our fire protection services.