Smoke control in HVAC system for more number of floors

An HVAC system can be implemented to serve on many floors. The normal HVAC system that serves all the floors of a building is shown below. For this building, the stairwells are pressurized in the event of a fire. The distribution ducts on each floor are shown in the picture.

Smoke control by pressurization and exhaust:

In the event of fire in the system:

  • The smoke damper in the return duct is open on the fire floor
  • The rest of the smoke damper in the return duct are closed
  • The smoke damper in the supply duct on the floor directly above and below the fire floor are open
  • The rest of the smoke dampers in the supply duct are closed.

These damper settings are intended to:

  • Concentrate exhaust on the fire floor
  • Concentrate pressurization on the floor above and below the fire floor
  • Prevent smoke from migrating to other zones through the return duct.

For this zoned smoke control system, the mode of operation of penthouse is explained in: click here

Smoke control by exhaust only:

The zoned smoke control consisting of the fire floor exhaust and exhaust of floor directly above and below the fire floor. In the event of fire in the system:

  • The smoke damper in the return duct are open on the floor and floor directly above and below the fire floor.
  • The rest of the smoke damper in the return duct is closed.
  • All smoke damper in supply duct are closed.