The CAV option allows you to model Constant Air Volume HVAC configuration with optional preheat, main AHU heating coils and zone terminal reheat and several different heating coil options. There are options to control the air distribution system in various ways including the ability to ensure minimum fresh air delivery to each zone, set various outside air options including an economiser to provide free cooling when appropriate and heating and cooling coil temperature reset .
Only one CAV system can be defined per building.
Note: the Compact HVAC type must be set to CAV at building level and in all zones which are part of the CAV system. Other zones can have HVAC type Unitary single zone or Fan coil units but not Unitary multizone or VAV.
See also Zone Terminal Units for more on VAV systems.