Trane LO manual Tracer ZN.520, UNT-IOM-6

Tracer® ZN.520

If a Low Temperature Detection diagnostic recurs within 24 hours after an automatic diagnostic reset, you must manually reset the diagnos- tic. See other possible methods for resetting diagnostics in this section.

Manual output test: You can use the Test button on the controller either during installation to verify proper end device operation or during troubleshooting.When you press the Test button, the controller exercises all outputs in a predefined sequence. The first and last outputs of the sequence reset the controller diagnostics. See the previous section for more information about the manual output test. Cycling power: When someone turns off the controller’s 24 VAC power, then re-applies power, the unit cycles through a power up sequence.By default, the controller attempts to reset all diagnostics at power up.Diagnostics present at power up and those that occur after power up are handled according to the defined unit diagnostics sequences (see previous Diagnostics table).

Building automation system: Some building automation systems can reset diagnostics in the Tracer® ZN.520 controller.For more complete information, refer to the product literature for the building automation system.

Rover™ service tool: Rover service tool can reset diagnostics in the

Tracer® ZN.520 controller. For more complete information, refer to the

Rover™ Installation, Operation, and Programming manual.

Diagnostic reset: Any device that can communicate the network variable nviRequest (enumeration “clear_alarm”) can reset diagnostics in the Tracer® ZN.520 controller.The controller also attempts to reset diagnostics whenever power is cycled.

Cycling the fan switch: If the user cycles the fan speed switch from off to any speed, the controller resets all diagnostics.Diagnostics may recur immediately if the problem still exists.

The green LED normally indicates whether or not the controller is powered on (24 VAC).

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