Trane TRACER SUMMIT BAS-APG001-EN Manuel D’Utilisation

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Applications of smoke control methods
BAS-APG001-EN
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Figure 4:  Sample HVAC operation during smoke control
When an HVAC system serves only one smoke control zone, the following 
sequence provides smoke control:
1.
In the smoke control zone, the return/exhaust fan activates, the 
supply fan deactivates.
2.
The return air damper closes, and the exhaust damper opens 
(optionally, the outside air damper closes).
3.
In the no-smoke zone, the return/exhaust fan deactivates, the supply 
fan activates.
4.
The return air damper closes, and the outside air damper opens 
(optionally, the exhaust air damper closes).
Stairwell smoke control
Stairwell smoke control uses pressurization to prevent smoke migration 
through stairwells to floors remote from the source of the smoke. 
Secondarily, it provides a staging area for fire fighters.
In the smoke control zone, a pressurized stairwell maintains a positive 
pressure difference across closed stairwell doors to limit smoke 
infiltration to the stairwell. Stairwell smoke control employs one or more 
of these design techniques: compensated pressurization, non-
compensated pressurization, single injection pressurization, and multiple 
injection pressurization.
Compensated pressurization technique
The compensated stairwell pressurization technique adjusts air pressure 
to compensate for various combinations of open and closed stairwell 
access doors. The technique maintains constant positive pressure 
differences across openings. To compensate for pressure changes, it either 
employs modulated supply airflow or over-pressure relief.
Note:
For simplicity, Figure 4 does not show the ducts on each floor or 
the penthouse equipment.