Codes 1400 and 1401 are the HIGH TEMPERATURE alarm: the generator is overheated. Generac says the cause is obstructed intake and exhaust ventilation around the unit or inadequate fuel pressure, and asks you to make sure there are no enclosures around the generator.
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0 of 4 completedCapture the exact state
ReversibleRecord the load, the weather, any debris, leaves or snow around the unit, how long it had been running and the moment it shut down.
Separate the likely fault domains
ReversibleDo not restart for a minimum of 30 minutes. With the unit off and cool, keep a clear 3-foot area at the front and both sides, remove debris, leaves, vegetation or snow, and check around the louvers, air intake and exhaust for anything that blocks airflow. In freezing weather check the air filter for ice, since moisture can freeze and block airflow to the engine. Check that the air filter is clean and that maintenance items are done. Generac tests units for operation from -20 degrees F to 122 degrees F, so consider extreme ambient temperatures.
Correct only the proven, accessible condition
ReversibleRemove the exterior blockage and complete due maintenance. Generac says low fuel pressure while running raises engine temperature, and that under heavy loads for longer than 24 hours the unit must be shut down every 24 hours for at least 30 minutes to cool and check the oil level, because skipping this can cause the HIGH TEMP alarm and damage. Leave fuel pressure, sensor, fan and internal cooling diagnosis to authorized service.
Verify once before going farther
ReversibleAfter cooling and confirming clearance and airflow, clear the alarm and restart the unit once. Never start a generator while it is under load.
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