Balancing The System Using Test & Balance Tool - Carrier VAV Zone II Installation And Startup Manual

Start-up
Do one of the following:
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Single Duct or Parallel Fan zone terminals – Click Cool Max Airflow to override the zone control and
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increase the airflow to the cooling maximum cfm (liters/second) . Check the zone for design cooling
maximum airflow using certified measuring devices. Enter the measured cfm (liters/second) and click
the arrow to enter the current sensor reading value.
Series Fan zone terminals – Click Damper Full Close to override the zone damper to its fully closed
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position. Wait 30 seconds after the damper is closed, select the Fan's Lock value to checkbox, then
select On in the droplist. Click Apply. You must follow this procedure to prevent the fan from turning
backwards. Check the zone for design cooling maximum airflow using certified measuring devices. See
the zone terminal manufacturer's instructions to adjust the fan speed to meet design airflow
requirements. After you set the fan speed to deliver the Cool Max Airflow, click the Cool Max Airflow.
Verify the airflow using a certified measuring device. Enter the measured cfm (liters/second) and press
the arrow to enter the current sensor reading value. Verify that the zone terminal plenum air intakes do
not have a positive airflow.
Check all branch duct terminal registers for design flow. If necessary, adjust the manual volume dampers in
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the branch ducts.
Single Duct or Parallel Fan zone terminals - Click Occupied Min Airflow to set the zone damper to its
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minimum airflow position. Verify the airflow using a certified measuring device. Enter the measured cfm
(liters/second) and click the arrow to enter the current sensor reading value.
Parallel Fan Zone Terminals only - To adjust Parallel Fan airflow, make sure Occupied Min Airflow is selected,
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select the Fan's Lock value to checkbox, then select On in the drop-down list. Click Apply. See the zone
terminal manufacturer's instructions on adjusting the fan speed to meet design airflow requirements. When
finished, clear the Fan's Lock value to checkbox.
If the terminal has ducted reheat, select the Flow Setpoint in the Locks section and enter Auxiliary Heat Min
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Airflow if it is greater than the Occupied Min Airflow. Select Auxheat and enter 100%. Click Apply. Verify the
supply air temperature rises for ducted heat. For non-ducted heat, physically verify that the heat is energized.
Deselect a Flow Setpoint and Auxheat and click Apply when finished.
Repeat steps 1 through 6 for each zone until all zones have been balanced. Make sure that you select
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Automatic Control before moving on to the next zone.
Balancing the system using Test & Balance tool
Use the Test & Balance tool to manipulate the controllers associated with an air source, but not the air source
itself or heating and cooling equipment such as chillers and boilers. See the Test & Balance Help for more
information on using the tool.
Most VAV system airflow designs are based on cooling requirements which require a greater cfm (liters/second)
flow than heating requirements. Using this balancing procedure, you adjust the cooling airflow first. If the heating
and cooling maximum airflow requirements are the same, you will not need to balance the heating airflow.
NOTE We recommend that the total heating minimum airflow settings for all the zones in the system be set to
maintain the air source's design minimum heat cfm (liters/second) airflow across its heat exchanger to prevent
damage to the equipment.
VAV Zone II Controllers
Installation and Start-up Guide
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