E08
DuroStar Utility Sensing Failure / ATS Communication Fault

Controller displays E08 and the generator will not start in AUTO mode when utility power fails.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Open or shorted utility sense wires, Faulty automatic transfer switch control board, Incorrect wiring between generator and ATS, Blown ATS control fuse

How to Fix / Troubleshooting

Safety first: Turn OFF the generator and lock out/tag out the main utility breaker. Only qualified persons should work inside the transfer switch.

  • Check controller settings: Verify that AUTO mode is enabled and that utility sensing parameters are correctly configured according to the DuroStar installation manual.
  • Inspect sense wiring: Locate the utility sense terminals on the generator control board and ATS. Check for loose, broken, or corroded wires. Tighten terminals and repair any damaged conductors.
  • Check ATS control fuse: Open the ATS enclosure and locate the low‑voltage control fuse. Test it with a multimeter and replace if open with the same rating.
  • Verify correct wiring: Compare the wiring between the generator and ATS to the DuroStar wiring diagram. Correct any mis‑wired terminals, especially sense and start/stop signal wires.
  • Test ATS operation: Simulate a power failure under controlled conditions and observe whether the ATS sends a start signal to the generator. If not, the ATS control board may be defective and require replacement.
  • Controller reset: After repairs, clear E08 and retest automatic start. If the fault returns, contact a technician to evaluate the ATS and generator control board communication circuits.
Advertisements

Repair Difficulty

Professional Required 5/5

Required Part

Automatic Transfer Switch Control Board
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements