Xenta 102-AX Airflow Setpoint goes to Unoccupied Minimum airflow setpoint when in heat mode

[Product_Support]

Issue

Xenta 102-AX goes to Unoccupied Minimum airflow setpoint instead of Heating Minimum airflow setpoint when in HVAC_HEAT mode

Environment

Xenta 102-AX version 2.17 and prior

Cause

Revision 2.12 of the 102-AX added the capability to do airflow reset in heat mode. To do that, it uses warmup high flow to create the range to reset. If that setting is lower than the heating minimum airflow setpoint, it does not know what to do and reverts to the unoccupied airflow setpoint.

Resolution

1. Set the warmup high flow setpoint to be greater than the heating minimum flow setpoint. The warmup high flow setpoint should not be set to 0 even if there is no warmup/central plant heat on the unit.
2. Alternatively, upgrading the Xenta 102-AX firmware to version 2.18 or newer.