How to troubleshoot a TemperZone Thermostat with no power LED on the main PCB?
- JJudith JohnsonAug 19, 2025
If the main PCB power LED is off on your TemperZone Thermostat, there could be several reasons. First, check if there is a loss of power to the main PCB and ensure the supply voltage is present. Also, inspect the PCB fuses for any failures. Verify that the 240V/24V switch is in the correct position. Finally, check if any other PCB LEDs are on, as the power LED itself might be faulty.






