Variable-Air-Volume System; Constant-Volume System; Ul-Tested Programs - Trane Engineered Smoke Control System Application Manual

Variable-air-volume system

Variable-air-volume system
For variable-air-volume (VAV) systems, some form of duct pressure relief
is required on each floor or in each smoke control zone. In smoke control
mode, all return and supply fans will be set to their highest speed. If the
VAV dampers are closed when this occurs, the duct pressure may be
enough to damage the ductwork. To avoid this possibility, duct pressure
relief dampers, either DDC or mechanically controlled, should be
installed in the ductwork for each smoke control zone.
It should be noted that careful sizing of smoke control supply air damper
and relief damper is necessary to use smoke purge and protect dampers.

Constant-volume system

For constant-volume systems in smoke control mode return/exhaust
dampers are open. Therefore, separate duct pressure relief is not
required, but may be necessary on each floor or in each smoke control
zone, as it is for VAV systems. Supply dampers should be sized such that
any one damper can spill an adequate amount of air.

UL-tested programs

This application guide showed only excerpts of UL-tested TGP programs.
Programs in their entirety can be found and downloaded from the GCS
Product Support Web site. These programs may or may not meet local
smoke alarm requirements. In all cases, defer to local smoke control
specifications.
BAS-APG001-EN 119