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Generac MDG100DF4 / MDG75DF4 — Manually Starting the Unit

Operation · Genset controller

For the Generac MDG100DF4 / MDG75DF4, from the Generac owner's manual.

Applies to: Generac MDG100DF4, Generac MDG75DF4

Before you start

  • Do not attempt to start a unit in need of repair or scheduled maintenance
  • Carbon monoxide/asphyxiation hazard

Procedure

  1. Set controller power to ON; the controller boots in STOP mode.
  2. Press engine START button; controller begins startup sequence if no faults.
  3. If engine fails to start within three crank attempts, alarm displays; wait 2 minutes to retry.
  4. Allow engine to warm for approximately 10 minutes before loading.
  5. Turn OFF the Low Idle Speed switch when engine is warm.
  6. Check for excessive noise, vibration, or coolant/oil/fuel leaks before applying loads.
  7. Verify AC output voltage and frequency are correct.
  8. Switch main circuit breaker ON, then switch on individual load breakers.

Source: Generac owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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