Boiler does not power on at all; display is blank and no lights or sounds are present.

Safety: Turn OFF power at the main panel before opening any electrical junction boxes or the boiler cabinet.

• 1. Check breaker and switch: Verify the dedicated boiler breaker is ON and any local service switch near the Noritz boiler is in the ON position.
• 2. Inspect power cord or wiring: Ensure the boiler's power cord (if equipped) is plugged in securely, or that hardwired connections are tight (electrician recommended).
• 3. Internal fuse: With power OFF, remove the front cover and locate the control board fuse. If blown, replace only with the same type and rating. If it blows again, stop and call a technician.
• 4. Professional diagnosis: If there is still no power, a technician should test incoming voltage, transformer output, and replace the control board or transformer as needed.