Fresh Air Damper Stays Open - Trane BCHC Installation & Operation Manual

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Maintenance
Table M-D-8. Fresh Air Damper Stays Open
Probable Cause Explanation
Normal Operation The controller opens and closes the fresh air damper based on the
controller's occupancy mode and fan status. Normally, the fresh air damper
is open during occupied mode when the fan is running and closed during
unoccupied mode.
Manual Output Test The controller includes a manual output test sequence that verifies analog
and binary output operation and associated wiring. However, based on the
current step in the test sequence, the fresh air damper may be open. Refer
to the"Manual Output Test" section.
Unit Configuration The controller must be properly configured based on the actual installed end
devices and application. When the unit configuration does not match the actual
end device, the damper may not work correctly.
Unit Wiring The wiring between the controller outputs and the fresh air damper must be
present and correct for normal damper operation. Refer to the unit wiring
diagrams on the unit.
Normal operation The controller opens and closes the fresh air damper based on the
controller's occupancy mode and fan status. Normally, the fresh air damper
is open during occupied mode when the fan is running and closed during
unoccupied mode.
Table M-D-9. Valves Stay Closed
Probable Cause Explanation
Requested mode off You can communicate a desired operating mode (such as off, heat,
and cool) to the controller. When off is communicated to the controller, the
unit controls the fan off. There is no heating or cooling (valves are
closed).
Power up control wait When power up control wait is enabled (non-zero time), the controller
remains off until one of two conditions occurs:The controller exits power up
control wait once it receives communicated information.The controller exits
power up control wait once the power up control wait time expires.
Manual output test The controller includes a manual output test sequence you can use to verify
output operation and associated output wiring. However, based on the
current step in the test sequence, the valve(s) may not be open. Refer to the
Manual Output Test section.
Fan mode off When a local fan mode switch (provided on the Trane zone sensor)
determines the fan operation, the off position controls the unit off and
valves to close.
Sampling logic The controller includes entering water temperature sampling logic which is
automatically invoked during 2-pipe and 4-pipe changeover when the
entering water temperature is either too cool or too hot for the desired
heating orcooling.Refer to the Entering Water Temperature Sampling
section.
Diagnostic present A specific list of diagnostic affects valve operation. For more information, see
the Diagnostics section.
Unit configuration The controller must be properly configured based on the actual installed end
devices and application. When the unit configuration does not match the
actual end devices, the valves may not work correctly. Example: A 2-pipe
heat/cool changeover unit will not cool if the entering water temperature is
too warm for cooling or if the entering water sensor is not present. The unit
will not heat if the entering water temperature is too cool for heating.
Unit wiring The wiring between the controller outputs and the valve(s) must be
present and correct for normal valve operation.
Random start observed After power up, the controller always observes a random start from 0 to 25
seconds. The controller remains off until the random start time expires.
Diagnostics
BCXC-SVX01A-EN