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Solar · Error codes · Zhejiang Deye Electrical Appliances Co., Ltd.
F18Zhejiang Deye Electrical Appliances Co., Ltd. · Deye SUN-SG04LP1-EU single-phase hybrid

F18 on a Zhejiang Deye Electrical Appliances Co., Ltd. Deye SUN-SG04LP1-EU single-phase hybrid: AC side over current fault

Short answer

On a Zhejiang Deye Electrical Appliances Co., Ltd. inverter, F18 means: AC side over current fault. The inverter stops until the fault clears or is reset.

Reviewed 24 September 2026 · 1 source

What it means

The manual says: AC side over current fault.

Part involved: AC output.

Likely causes:

  • Backup/common load power out of range.

Is it safe?

Does the inverter stop?Yes
SeverityFault — clears by itself when the condition goes

The inverter stops until the fault clears or is reset.

Resetting itself: yes.

Manual reset: Restart and check.

What you can check

  • Read the full code and message on the inverter screen or in the Deye Cloud / installer app and note the date/time for your installer.
  • Check the inverter's AC isolator next to the inverter and the solar/battery breaker in the consumer unit are ON (do not reset a breaker that trips again - call your installer).

What the engineer will check

  • Check load power vs rating.

Who to ask for: Qualified electrician / MCS PV installer.

Certification: Battery and hybrid-inverter DC work: installer trained/approved by the manufacturer; electrical work under BS 7671 by a competent person.

What you might notice

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 24 September 2026