How do I fix Over-Temperature / NTC Fault on a Growatt?

Check ambient temperature and ventilation clearances (min 200 mm clear above and sides). Check heat sink for dust or debris Then: If temperature is high, improve ventilation or provide shading. Allow inverter to cool and retry

Growatt

Error 408

Over-Temperature / NTC Fault

Inverter internal temperature is too high, or the NTC temperature sensor has failed.

Common causes

Ambient temperature too highPoor ventilationDirect sunlight on inverterBlocked heat sinkNTC sensor open circuit

What to check

STEP 1

Check ambient temperature and ventilation clearances (min 200 mm clear above and sides). Check heat sink for dust or debris

STEP 2

If temperature is high, improve ventilation or provide shading. Allow inverter to cool and retry

Escalate if

Fault occurs at normal ambient temperatures with good ventilation — NTC sensor or cooling hardware fault, escalate

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