American Power Conversion DX ユーザーズマニュアル

Env Temperature Low

• Verify that no supply air is fed directly back into the return air.
• Ensure that the alarm delay is not set too low. The delay should be long 

enough to allow the room temperature to stabilize after start-up.

• Verify that the temperature alarm threshold for the environmental (return or 

remote) sensors is 7 - 10°F below the reheat setpoint.

• Verify that the Module is configured and equipped for the reheat mode.
• Ensure that the reheat mode is enabled and working properly.
• Ensure that the reheat mode is not disabled because of an active user-defined 

input mapped to nonessential lockout. 

Exp Module # 1 
Communication Lost

• Verify the System CAN connections in the user interface box are connected 

correctly and properly terminated.

• Check the CAN addresses assigned with the DIP switches on the controller 

board on the electrical panel. N

: The controller must be restarted to 

recognize an address change.

Exp Module # 2 
Communication Lost

• Verify the System CAN connections in the user interface box are connected 

correctly and properly terminated.

• Check the CAN addresses assigned with the DIP switches on the controller 

board on the electrical panel.

Fire Detected

• Follow the appropriate facility emergency protocol. N

: The purpose of 

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

• Confirm that the wiring connections are secured to the wiring harness.
• Verify the fire detector (firestat) is set to 125°F.
• Reset the firestat by pressing the reset button on the firestat.
• Replace the fire detector (firestat).

Fluid Coil No Coolant Flow

• Verify chilled water supply.
• Check the operation of the flow switch.
• Check the electrical connection to the flow switch.
• Verify that the Economizer automatic coolant isolation valve is open (if 

equipped).

• Verify that the valve type setting is correct in the System Configuration 

(Path: Main > Setup > System # > System Config > Valve Types).

Fluid Coil Actuator Fail

• Verify the proper connections between the actuator and the controller board.
• Confirm that the control voltage and signal voltage reach the actuator.
• Ensure that the proper Module Configuration is defined for this Module, 

especially that the coil Configuration and the MultiCool/Economizer actuator 
type are correct.

• Replace the fluid coil actuator.

Fluid Coil Coolant Temp High

• For Economizer Modules, check the operation of the outdoor heat exchanger.
• For MultiCool Modules, check the chilled water supply temperature.
• Verify that the fluid coil coolant temperature high threshold is not set below 

the normal temperature of your chilled water supply.

Fluid Coil Coolant Temp Low

• For Economizer Modules, check the operation of the outdoor heat exchanger.
• For MultiCool Modules, check the chilled water supply temperature.
• Verify that 

the low threshold for the fluid coil coolant temperature is not 

set above the normal temperature of your chilled water supply.