Major changes in Xenta 102-AX version 2.19

Issue

Xenta 102-AX version 2.19 included 6 major updates and changes. They are outlined below.

Product Line

TAC Vista

Environment

  • Vista
  • Xenta 102-AX

Cause

1 - M/STAT Air Flow Calibration Errors

Error Description: When calibrating a Xenta 102-AX using the M/STAT a Velocity Pressure Offset is not generated in circumstances where one would be generated in the 102-AX Plug-in. This adversely affects the accuracy of the calibration, in particular at the low flow setting.

Note: All steps for calibration using the M/STAT are found in Lessons Learned Article #3988

Workaround: Perform the calibration using the LNS 102-AX plug-in tool or the TMGL plug-in tool

2 - Xenta 102-AX does not perform wink function properly

Error Description: Attempts to perform the wink function fail. When a wink function is performed, the red light on the controller is expected to come on and flash to identify the controller and the STR-250 should display "00" with the man logo displayed as well. This should last approximately 45 seconds.

3 - STR-250 connected to the Xenta 102-AX is not controlling the fan properly

Error Description: The STR-250, stat when connected to the Xenta 102-AX, reacts incorrectly to buttons being pressed when in the fan menu. The increase button causes a decrease and the decrease button causes an increase among other odd behaviors. Also, if the fan is set to shut off (this action should not be allowed) the Xenta 102-AX performs a resynchronization.

4 - Pressure dependent mode erroneously requires airflow and fan enabled

Error Description: The 102AX requires 80% Airflow Setpoint to run Heat1 in Pressure Dependent mode.

5 - Xenta 102-AX Hot Water floating control resynch fails

Error Description:  When the Xenta 102AX does a hot water floating control valve resynch based on being in the 10-90% "happy" zone for 60 seconds and then goes to 100% it does not resynch at the 100% open position for the full stroke time. It gets to 100% commands the resync, then closes the valve, re-opens the valve to 100% then allows the valve to control back to a normal position.

6 - Xenta 102-AX Floating Hot Water valve control failures

Error Description:  Heating outputs stop working on Xenta 102-AX sporadically causing hot water valve to open even though application is calling for it to be closed. This occurs when the 102-AX is set up for a floating valve actuator (PWM 2) and occurs sometimes within a day but could take a few of days to show up. The resynchronization of the valve seems to have no effect and the only way to fix the controller is to cycle power or by switching nviEmergCmd to something other than its default and then back again a moment later.

Resolution

If any of these errors are occurring, upgrade the Xenta 102-AX to version 2.1.9 or higher. Click here to download the APB file.

Complete upgrade instructions can be found at Lessons Learned Article #3899

Version 2.19 addresses the problems listed above as follows:

1 - M/STAT Air Flow Calibration Errors

Fix: When calibrating a Xenta 102-AX using the M/STAT a Velocity Pressure Offset is now properly generated.

2 - Xenta 102-AX does not perform wink function properly

Fix: After clicking Wink the a red LED on the controller flashes to identify the controller and the STR-250 displays "00" and the man icon. After approximately 45 seconds both the controller and the STR-250 return to normal.

3 - STR-250 connected to the Xenta 102-AX is not controlling the fan properly

Fix: The ability of the STR-250 to override the fan command on the 102-AX is disabled by default. If this functionality is required it can be turned on by setting DamperActuator.SCPTdirection.bit15 to 1.

4 - Pressure dependent mode erroneously requires airflow and fan enabled

Fix: The 102AX no longer requires 80% Airflow Setpoint to run Heat1 in Pressure Dependent mode.

5 - Xenta 102-AX Hot Water floating control resynch fails

Fix:  Logic has been corrected to only resynch open or resynch closed as needed. Additionally, the heating output resynchronization algorithm has changed to operate as follows:

Two internal timers have been added to track the accumulated amount of time that heat load is 0% and at 100%. Once either of these timers reaches 30 minutes, a resynch is initiated in the respective direction of the timer. The resynch consists of activating either the open or close triac output for an amount of time equal to the user defined stroke time.

6 - Xenta 102-AX Floating Hot Water valve control failures

Fix:  Heating output logic corrected to prevent failure.