The Equipment Interface has four LEDs to display the status of the system.
If you’ve wired the system correctly, only the Power LED should be on.
The LEDs operate as follows:
Power This LED monitors the power supply of the Equipment Interface.
LED ON Power is connected to the Equipment Interface and is within the appropriate voltage range.
LED OFF Power is disconnected or has dropped below 9V.
System This LED monitors the operation of the Equipment Interface.
LED ON There is a fault with the Equipment Interface.
LED OFF The equipment interface is operational.
Line This LED monitors the power supplied to the Thermostat from the Equipment Interface.
LED ON The voltage at the +12V and GND terminal has dropped below 7V.
LED OFF Adequate power is being supplied to the Thermostat.
Communication This LED monitors the communication between the Thermostat and the Equipment Interface (i.e., the D+ and D- terminals).
LED ON The Equipment Interface and Thermostat are not communicating with each other.
LED OFF The two devices are communicating properly.