Read the manual thoroughly and understand all of the instructions, cautions, and warnings before using this equipment. If any section of the manual is not understood, contact your nearest authorized dealer, or contact Generac Customer Service at 1-888-436-3722 (1-888-GENERAC), or www.generac.com with any questions or concerns.

Troubleshooting generator startup with utility power present

If your generator is running and you have confirmed that utility power is present in your home, follow these troubleshooting steps:

Note: Generators may also start during a brownout (when utility voltage drops too low to safely power the house). This can cause the generator to start when it appears that utility power is still present. Generac offers solutions to address regular brown outs: What is a brownout?

Environment

• This article applies to Generac air-cooled home standby generators.
• This article addresses a scenario where a generator starts even though the utility power did not cut out. For more power transfer troubleshooting, see: Home standby generator power transfer issues: Troubleshooting the Automatic Transfer Switch

Troubleshooting steps

1. Generator - The generator may be exercising. Guardian series generators with Evo 1 or Evo 2 controllers do not transfer loads during an exercise. Next Generation series generators can perform a power load transfer during exercise. See the What Is a Generator Exercise? article for more information.
2. Mobile Link & Control Panel - Check Mobile Link or the generator's control panel for error codes or alarms: Where can I find a list of error codes for my generator?
   • Any time the generator has an active error or alarm, it will turn the unit off and display that error code.
   • To clear the error code:
     • For Evolution controllers: Press OFF, ENTER twice, then AUTO.
     • For Power Zone 200 controllers: Hold the OFF button for 3 seconds.
   • If the error code returns, follow the recommended troubleshooting to resolve it. Some error codes require attention from a service dealer: What Error Codes Do I Need to Call a Dealer For?
3. Transfer Switch - Verify the utility service disconnect is ON or CLOSED.
   • The utility service disconnect is the breaker immediately after the utility meter. This may be in the home's main panel, automatic transfer switch, or a stand-alone box.
   • If you have confirmed that utility power is present, and the transfer switch is in the utility position, it is safe to turn the generator OFF at the control panel.
   • If you have confirmed that utility power is present, and the transfer switch is in the standby source or generator position, follow this process to safely shut down the generator: How Do I Shut Down My Generator When It’s Powering My House (During an Outage)?
   • For next steps, we recommend reaching out to a Generac authorized service dealer.

Other power transfer articles

• Home standby generator power transfer issues: Troubleshooting the Automatic Transfer Switch
• How do I manually operate an automatic transfer switch?
• How does an Automatic Transfer Switch work?
• Why didn’t power switch over to the generator after losing utility power?
• What is an Automatic Transfer Switch (ATS)?
• Difference between partial and whole-home automatic transfer switches
• What is the purpose of home standby generator control wires?
• Where is the T1 fuse on my home standby control panel?