1. Check the main power at the unit. Check any breakers associated with the unit you are working on. Once high voltage is determined not to be the issue move on to the low voltage power.
2. When first powered up, the Supervisor will have a flashing green RUN LED. The boot process takes approximately 15 seconds. Once the Supervisor completes the boot process, the RUN LED will be solid green.
a. If there is no RUN LED on power up, check AC voltage on the 24H/24L terminals.
b. If the RUN LED continues flashing and is not solid, the Supervisor failed the boot process and needs to be replaced.
3. If the RUN LED is not on, verify that the phoenix connector is securely fit into the port on the Supervisor. Also verify that wires are securely fit into the terminals of the phoenix connector.
4. Verify AC voltage on the Supervisor 24H/24L terminals using a multimeter. You should be getting within +/- 10% of 24VAC.
5. Verify polarity of 24VAC wiring going into Supervisor terminals 24H/24L. The power wire (+) of the 24VAC power source needs to be landed on the terminal labeled 24H and the common (-) needs to be landed on the terminal 24L. Improper termination can cause issues with the SMC Supervisor. See photo at beginning of this section for more information.
6. If verification of the wires has been completed at the Supervisor and issues continue, power at the 24VAC power source needs to be checked. Trace the 24VAC wire back to its origin point. This may be a transformer, or it could be on the R and C terminals where the thermostat for the unit connects. Verify solid connections. Also see if 24VAC is present using a multimeter. Look for any low voltage fuses that could have blown. These are usually between 2 amp and 5 amp in nature and located on the main control board of the unit.