External Switch or Sensor Not Working — External accessory function not enabled

What does External Input Not Active mean?

An external switch function or sensor connected to the F750 (e.g., to AUX1-AUX5 or AA3:X7) is not functioning as expected. This usually means the input or output function for that connection has not been correctly selected in the heat pump's software.

• Function for the external input/output is not activated or incorrectly selected in the heat pump's menu system

Click steps to track your progress.

1. 1

   Access the heat pump's menu system on the display.

2. 2

   Navigate to Menu 5.4.

3. 3

   Select the correct function for the specific external input or output (e.g., AUX1, AUX2, AUX3, AUX4, AUX5, or AA3:X7) that is connected.

4. 4

   Ensure the external switch or sensor is correctly wired and physically connected to the input card (AA3).

5. 5

   Test the external device after making the software selection.