CNT-SVX11A-EN 39
Troubleshooting
Probable cause Possible Explanation
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 5 to 30 seconds. The controller
remains off until the random-start time expires.
Power-up control wait When power-up control wait is enabled (non-zero time), the controller remains off until one of two
conditions occurs:
1. The controller exits power-up control wait once it receives communicated information.
2. The controller exits power-up control wait once the power-up control wait time expires.
Diagnostic present A specific list of diagnostic affects valve operation. For more information see, Table 19 for more
information
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. For more information see, Manual Output Test, on page 32 for more information.)
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.
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).
Sampling logic The controller includes entering water temperature sampling logic which is automatically invoked
when a waterside economizer or boilerless control is present. For more information see, Entering Water
Temperature Sampling, on Sampling logic page 26 for more information.)
Table 20:
Isolation valves stay closed
Probable cause Possible Explanation
Unit wiring The wiring between the controller outputs and the valve(s) must be present and correct for normal
valve operation.
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 be
open. For more information see, Manual Output Test, on page 32 for more information.)
Sampling logic The controller includes entering water temperature sampling logic which automatically invoked during
when waterside economizer or boilerless control is present. For more information see, Entering Water
Temperature Sampling, on page 26 for more information.)
Normal operation The controller opens and closes the valves to meet the unit capacity requirements.
Table 21:
Isolation valves stay open
Valves
To Next Page
Loading...
Need help?
General
