Trane VAV-UCM 4.2, Инструкция по установке и обслуживанию

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68 VAV-SVX01C-EN
Troubleshooting
UCM board on TB1-1 and TB1-2. Should measure 24 VAC ± 10%. If you measure the proper
voltage at TB1-1 and TB1-2 and no voltage at TB3-1and TB3-2 replace UCM.
Note: If no voltage at TB1-1 and TB1-2 see UCM see UCM failure procedures
• Disconnect the receiver sepoint wires on the VAV UCM on terminals TB3-2 and TB3-3 and
measure the VDC. It should be 5VDC. If 5VDC is not present check incoming power to the
UCM board on TB1-1 and TB1-2. Should measure 24 VAC ± 10%. If you measure the proper
voltage at TB1-1 and TB1-2 and no voltage at TB3-2and TB3-3 replace UCM.
Note: If no voltage at TB1-1 and TB1-2 see UCM see UCM failure procedures
Airflow Failure Procedures
In the event that the air valve is reading position instead of flow or in the event that the measured
flow reads incorrectly, i.e. different from the balance report, properly inspect the following:
• Recalibrate VAV unit by cycling power to unit. This can also be accomplished with Rover,
Summit or CCP software.
Note: Cycling power to the VAV board will automatically cause the unit to calibrate, however,
following the procedure outlined below will provide a more accurate calibration. It is
only necessary to perform this procedure in instances where you are experiencing
incorrect flow readings or if the unit reverts to pressure dependent mode despite being
above 5% and below 110% of cataloged flow and performing a "normal calibration")
does not correct the problem.
1. Steps for Calibration
• Log on to the UCM with Rover software.
• Turn the central air handler "off." If this is not possible, Trane recommends pulling the
transducer tubes off during the calibration process to simulate this.
• Select the "calibrate unit" option button
• Rover software will indicate that calibration is taking place in diagnostic log
Figure 38. Rover software