American Power Conversion Central Air Conditioning System Benutzerhandbuch

Remote Sensor Added

• Check the CAN bus connection to the remote sensors.
• Disregard if you added the remote sensor.

Replace Steam Cylinder

• Replace the steam cylinder.
• Clean the steam cylinder (if your System is equipped with reusable 

humidifier cylinders).

Return Sensor Fail

• Verify that there is a proper CAN connection between the sensors and the 

user interface box.

• Replace the sensor assembly.

Secondary Sensors Failed

• Verify that there is a proper CAN connection between the sensors and the 

user interface box.

• Replace the sensor assembly.

Smoke Detected

• Follow the appropriate facility emergency protocol. N

: The purpose of 

the smoke sensor is to warn you of possible equipment damage. It is NOT 
intended to provide a smoke alarm system to protect the facility and the lives 
of its occupants.

• Confirm the wiring connections are secured to the wiring harness.
• Ensure smoke head and sub-base are properly attached. 
• Ensure that there is not dirt or dust on the smoke head. Use pressurized air to 

clean the smoke head chamber.

• Replace the smoke detector.

Supply Sensor Fail

• Verify that there is a proper CAN connection between the sensors and the 

user interface box.

• Replace the sensor assembly.

Supply Temperature High

• Ensure that the alarm delay is not set too low. The delay should be long 

enough to allow the Module to control the temperature after start-up.

• Verify that the supply air temperature alarm threshold is set above the cool 

and reheat setpoints.

• Verify that there is proper airflow through the Module (check the pressure 

drop across the evaporator coil).

• Ensure that the cool mode is enabled.
• Ensure that the cool mode is not disabled because of an active user-defined 

input mapped to nonessential lockout.

Supply Temperature Low

• Ensure that the alarm delay is not set too low. The delay should be long 

enough to allow the Module to control the temperature after start-up.

• Verify that the Module is configured and equipped for the reheat mode.
• Ensure that the supply air temperature alarm threshold is set below the reheat 

and cool setpoints.

• Ensure that the reheat mode is enabled.
• Ensure that the reheat mode is not disabled because of an active user-defined 

input mapped to nonessential lockout.

• Verify that there is proper airflow through the Module (check the pressure 

drop across the evaporator coil).

System Comm Lost

• Check that the System is receiving power.
• Check the external CAN bus connections.
• Check the System ID DIP switch settings of every Main Module in the 

Group. Each Main Module must have a unique address. See the Installation 
Manual for the correct DIP switch settings.