Overriding Vavs; Resetting Diagnostics - Trane VAV-UCM 4.2 Installation & Maintenance Manual

To enter the service mode:
1. Connect to the Comm4 link and scan for devices. See 'Accessing Rover/Comm4'
2. In the device list on the left side of your screen, double-click the controller that you want to place
3. Click the Enter Service Mode button. While the controller is in the service mode, it appears
To exit the service mode, do one of the following:
•
•

Overriding VAVs

When you override a controller, Rover Comm4 automatically places the controller in the service
mode. The controller is automatically released from the service mode after 15 minutes or when you
click the Exit Service Mode button for the device. You can manually release overrides by selecting
the appropriate release command in the Override dialog box.
1. On the Tools menu, click Overrides.
2. Select whether to override TUCs or VAVs.
3. Click the units you want to override.
4. In the list of overrides, click the type of override you want to perform.
5. Click the Override button. The controller automatically enters the service mode and exits the

Resetting Diagnostics

You can reset diagnostics only for TUCs (not VAV units).
1. In the device list on the left side of your screen, double-click the controller for which you want
2. Click the Diagnostics button.
3. Click the Reset button. Rover Comm4 attempts to clear all diagnostics on the controller and a
4. Click OK to close the message and the Diagnostics dialog box. You can click the Diagnostics
Saving VAV Program
Each VAV unit with a UCM 4.2 has been factory commissioned with a program that can be saved
to your hard drive.
This can be used to save the original program for a backup in case unit needs to be put back to
original specifications or to download into a UCM 4.2 DDC controller that has like parameters that
has been corrupted.
1. Select the Configure button, and the Configuration screen will appear.
VAV-SVX01C-EN
in the service mode.
in bold in the device list.
Wait for 15 minutes (Rover Comm4 does not need to be online with the controller).
For each controller in the service mode, click the Exit Service Mode button.
service mode 15 minutes after receiving an override.
to reset diagnostics.
message appears.
button again to verify which diagnostics have been cleared.
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