Description

This addendum adds requirementsto ensure that the air distribution system is capable ofdelivering outdoor air to the occupied spaces. In systems withAC units, heat pumps, or fan-coil units mounted in the ceilingor floor plenum, ventilation air is often supplied to the plenumto mix with recirculated air. Where outdoor air is poorlydistributed in such systems, units that are far from the outdoorair supply to the plenum may not receive the intended levels ofoutdoor air. In any air distribution system, required airflowcan only be assured by measuring actual airflow and adjustingdampers and orifices to account for the effect of as-installedduct pressure drops, i.e., the system must be balanced. Designersmust consider and make provision for system balancing.Note that balancing is addressed in terms of designing thesystem so that it can be balanced; this addendum does notrequire balancing at any particular time, as that issue iscovered in other addenda. Also, note that balancing is not aone-time event but must be reevaluated over time as indicatedin other sections of the standard.

Product Details

Published:

2002

ANSI:

ANSI Approved

File Size:

1 file , 400 KB