Trane ZN. LonWorks control, Руководство пользователя

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CNT-SVX13B-E4 31
Troubleshooting
Probable cause
Unit wiring
No power to the controller
Unit configuration
Random start observed
Power-up control wait
Diagnostic present
Manual output test
Fan mode off
Requested mode off
Unoccupied operation
Cycling fan operation/continuous
Explanation
The wiring between the controller outputs and the fan relays and contacts must be present and
correct for normal fan operation.
If the controller does not have power, the unit fan does not operate. For the Tracer ZN.520 zone
controller to operate normally, it must have an input voltage of 24 VAC. When the green LED is off
continuously, the controller does not have sufficient power or has failed.
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 fans may not
work correctly.
After power-up, the controller always observes a random start from 5 to 30 seconds. The controller
remains off until the random start time expires.
When power-up control wait is enabled (non-zero time), the controller remains off until one of two
conditions occur: 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.
A specific list of diagnostics affects fan operation.
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 unit fan may
not be on.
When a local fan mode switch (provided on the Trane zone sensor) determines the fan operation, the
off position controls the unit 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.
When the controller is in the unoccupied mode, the fan is cycled.
The controller operates the fan continuously when in the occupied, occupied standby, or occupied
bypass mode. When the controller is in the unoccupied mode, the fan is cycled between high speed
and off with capacity.
Questionable unit operation
Table 8 - Fan outputs do not energize
Probable cause
Unit wiring
Random start observed
Unit configuration
Power-up control wait
Diagnostic present
Manual output test
Fan mode off
Requested mode off
Sampling logic
Explanation
The wiring between the controller outputs and the valve(s) must be present and correct for normal
valve operation.
After power-up, the controller always observes a random start from 5- 30 seconds. The controller
remains off until the random start time expires.
The controller must be properly configured based on the installed end devices and application. When
the unit configuration actual does not match the actual end devices, the valves may not work
correctly.
When power-up control wait is enabled (non-zero time), the controller remains off until one of two
conditions occur: 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.
A specific list of diagnostic affects valve operation.
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.
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.
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).
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 or cooling. Refer to "Entering water temperature sampling function" on
page 9.
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. If failed the controller will close valve for one
hour then re-attempt sampling routine.
Table 9 - Valves stay closed