Air Balance Functions; Zone Sensor Air Balance Function - Trane Tracer VV550 Installation, Operation And Maintenance Manual

Air Balance Functions

There are two functions which enable air balancing: zone sensor air balance function and
communicating air balance function.

Zone Sensor Air Balance Function

A single point air balance function can be initiated at the zone sensor. Place the
thumbwheel at either the maximum (double star [**]) or the minimum (single star [*])
flow override position and press the CANCEL button for 10 seconds. If single point air
balancing is used, it should be done at the maximum flow override position, since the
airflow measurement is more accurate.
Note: Both the enable thumbwheel setpoint and the enable thumbwheel single star (*)
When the zone sensor air balance sequence initiates, the configured airflow
measurement offset is set to zero and the configured airflow measurement gain does not
change. When the zone sensor air balance sequence is active, the zone sensor ON and
CANCEL buttons do not generate timed override requests.
The controller controls the primary airflow to the configured maximum airflow (double
star) or the configured minimum airflow (single star) for the duration of the flow balance
operation.
Once in flow balance operation, each momentary (one second) press of the zone sensor
ON button or CANCEL button increases (ON) or decreases (CANCEL) the configured
airflow measurement gain by 0.005 (configured nominal airflow divided by configured
minimum airflow or configured maximum airflow). The user can use either the
configured maximum airflow or the configured minimum airflow as the calibration point
(single point calibration).
To exit this sequence, turn the thumbwheel away from the single star or double star
positions and toward the normal operation region. Once initiated, there is a 60-minute
time out. On exiting the flow balance operation, the controller permanently stores the
new value of the configured airflow measurement gain.
A dual point calibration method is available through the communicating air balance
function. Dual point calibration data present in the controller is overwritten when the
zone sensor is used for single point calibration.
The configured airflow measurement gain in the controller is the same as the cooling
flow correction factor in the VAV 4.2 controller.
Zone sensor air balancing has priority over the communicated flow overrides. This is the
only time local has precedence over communicated.
CNT-SVX17G-EN
and double star (**) function boxes must be checked in configuration.
Sequence of Operations
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