Honeywell Centra Line MERLIN NX Series Installation Instructions Manual page 29

Controller LED Status
Mode
Firmware download
a)
No application
Broken sensor
Short circuit
AutoMac
No Valid Mac
Un Ack Alarm
Normal operation
Communication error
a)
While performing setpoint balancing using the VAV mobile application, the LED pattern changes from static green to red, green, yellow
cycles (which indicates the controller is empty).
b) For troubleshooting a permanent red LED, navigate to IRM Program > On Board IO and check the UIO function block OutCase status.
A permanent red LED will be illuminated when the OutCase status is SensorOpen (broken sensor) or SensorClose (short circuit).
MERLIN NX IP AND MST/TP VAV CONTROLLER - INSTALLATION INSTRUCTIONS
Table 12. Controller LED Status
LED Status
Green blinks every 200 ms.
Red, Green, Yellow blinks every 1 s.
b)
Red permanent ON .
Green blinks every 2 s.
Yellow permanent ON.
Yellow blinks every 2 s.
Green LED permanent ON.
Red LED blinks every 200 ms.
29
Visual
EN1Z-1076GE51 R0722