46
Problem
Possible Cause
Solution
Fan Does Not Run
No Power to the Fans
Cycle power on/off the unit.
Confirm that power is applied to the unit at the main disconnect.
Confirm that power is applied to each fan by checking terminals
Check all terminals for tightness.
Check power wires at fan housing.
Check all terminals at Modbus module for tightness.
Fan Internal Fault
Check for the fan alarm on the controls user interface for Fan internal fault
Control Signal Issue
Check with a meter the control voltage at terminals -V, 10V or mA depending on control
signal.
Ensure a fan speed control signal is being sent to the unit.
Fan Spins Backwards
Fan is Off/Faulty
Turn the unit off. Allow all fans to stop completely. Check all breakers and power
connections. Restart the unit and ensure all fans are operational and make sure the fan
spins in right direction, and if it does not contact your local BAC representative.
Fan Does Not Respond to the
Control Signal
Communications Fault
Ensure the communications cable is connected to the controller on port J26.
Ensure the communications cable is not cut or damaged.
Ensure the communications cable is properly connected at the fan motor..
No Spray Water
or
Pump Does Not Run
Incorrect Set Point
Check the leaving the process fluid temperature set point on the controller and the
operating mode. The spray pump will only run when the ambient temperature is above 35°F
(1.67°C). For additional details, see “Cold Weather Operation” on
page 13
.
No Water Supply
Ensure water is being supplied to the solenoid make-up valve
Inspect solenoid make-up valves, and clean as required.
Check mechanical makeup valve and float assembly by manually raising and lowering the
float.
Pump Fault
Check pump voltage, and confirm that pump operates correctly in Manual Mode.
Pump Strainer Fault
Clean the pump strainer quarterly.
Water Distribution
System Clogged
Clean the spray branches and the nozzles. See
page 25
for more details.
NEXUS
®
MODULAR HYBRID COOLER
Troubleshooting Guide
7
Table 4.
Troubleshooting Guide
