Monitoring duct temperature on a Xenta 102-AX without putting it into Morning Warmup (Central Plant Heat) mode

[Product_Support]

Issue

Monitoring duct temperature on a Xenta 102-AX without putting it into Morning Warmup (Central Plant Heat) mode

Environment

Xenta 102-AX

Cause

The Xenta 102-AX Plug-in allows you to configure the hardware inputs for several different purposes.  If you configure Universal Input 1 as a duct temperature, that is assuming duct inlet temperature.  Any time the duct inlet temperature is higher than the room temperature (suggesting that central plant heat is being provided by the air handler) the action of the damper will reverse and the box will show HVAC_MRNG_WARMUP as its application mode.  If it is really the duct reheat outlet temperature that is being measured, this could be an undesirable result.

Resolution

There are two options to read in a duct temperature without it affecting the internal logic of the Xenta 102-AX.  The recommended method is:

1. Connect the temperature sensor to Universal Input 1.
2. Configure the Xenta 102-AX Plug-in, Hardware Configuration, Input 1 Section to "None."
3. This will continue to report the temperature on UnivIn1_Sense.nvoAuxTemp1 but will not affect the internal logic of the controller.

The other option is:

1. Connect the temperature sensor to Universal Input 3.
2. Configure the Xenta 102-AX Plug-in, Hardware Configuration, Input 3 Selection to "OA Temp. Sensor."
3. This will report the temperature on UnivIn3_Sense.nvoAuxTemp2 but will not affect the internal logic of the controller.