What does error W09 mean on a DEYE inverter?

W09 means: External Fan 3 Warning. External fan 3 is not connected correctly or is not operating normally.

Is error W09 a fault or a warning?

W09 is a warning: the red LED flashes and the unit keeps running. Fix the underlying condition before it escalates.

W09

DEYE inverter error W09

External Fan 3 Warning

Warning — the red LED flashes and the inverter keeps running. Deal with it before it escalates.

SUN SG01HP3/SG02HP3 Hybrid

InverterWarning

Also applies to:SUN-5K-SG01HP3-EU-AM2SUN-6K-SG01HP3-EU-AM2SUN-8K-SG01HP3-EU-AM2SUN-10K-SG01HP3-EU-AM2SUN-12K-SG01HP3-EU-AM2SUN-15K-SG01HP3-EU-AM2SUN-20K-SG01HP3-EU-AM2SUN-25K-SG01HP3-EU-AM2+9

What it means

External Fan 3 Warning — FAN_OUT3_Warn - external fan 3 is operating abnormally.

Cause: External fan 3 is not connected correctly or is not operating normally.

How to fix it

Check whether the fan is connected correctly and operating normally.

Source: 037_BManual_SUN-5_6_8_10_12_15_20_25K-SG01HP3-EU-AM2_20260224_en_9ef2717c.pdf, p.48 · 050_BManual_SUN-29.9_30_35_40_50K-SG01HP3-EU-BM3_4_20260224_en_544e1b2f.pdf, p.49 · 062_BManual__SUN-60_70_75_80K-SG02HP3-EU-EM6_20260224_en_38cbc9f6.pdf, p.49

Frequently asked questions

What does error W09 mean on a DEYE inverter?: W09 means: External Fan 3 Warning. External fan 3 is not connected correctly or is not operating normally.
Is error W09 a fault or a warning?: W09 is a warning: the red LED flashes and the unit keeps running. Fix the underlying condition before it escalates.
How do I clear or fix error W09?: Check whether the fan is connected correctly and operating normally.

Related error codes

Other codes on the SUN SG01HP3/SG02HP3 Hybrid

All SUN SG01HP3/SG02HP3 Hybrid codes

Prefer the full written guide? Read the complete DEYE inverter error-code guide

Compiled from official DEYE user manuals. Always consult your device manual and a qualified technician before performing repairs.