What does error W04 mean on a Felicity inverter?

It depends on the model — 2 devices use code W04. On the IVEM8048-II it means: Grid anomaly. The card for each model on this page gives its exact meaning and fix.

Is error W04 a fault or a warning?

It depends on the model: on some models W04 is a fault (output cut, red LED solid), on others a warning (red LED flashing, unit keeps running). Check the card for your model on this page.

How do I clear or fix error W04?

Check whether the input is overvoltage or overfrequency. The exact steps for each affected model are listed on this page.

W04

Felicity inverter error W04

Grid anomaly

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

Severity differs by model — check your model below.

The exact meaning depends on your model:

IVEM8048-II

InverterWarning

Also applies to:IVEM12048-IIIVEM 8K-12K Series II

What it means

Grid anomaly — Warning: Grid anomaly. Grid icon blinking.

Cause: Grid input is over voltage or over frequency.

How to fix it

Check whether the input is overvoltage or overfrequency.

Source: IVEM8K-12K-II_compressed.pdf, p.42

T-REX-50KHP3G01

InverterFault

What it means

Battery 2 undervoltage alarm — Battery 2 voltage is too low, the battery should be charged.

Cause: Battery 2 voltage has fallen to the undervoltage alarm threshold — the warning stage before the undervoltage fault; the pack should be charged.

How to fix it

Power down the inverter, wait 5 minutes for capacitors to discharge, then restart.
If the fault recurs immediately or repeatedly, record the exact code and contact your installer or the manufacturer's service line.

Source: T-REX-50KHP3G01-user-manual-.pdf, p.44

Frequently asked questions

What does error W04 mean on a Felicity inverter?: It depends on the model — 2 devices use code W04. On the IVEM8048-II it means: Grid anomaly. The card for each model on this page gives its exact meaning and fix.
Is error W04 a fault or a warning?: It depends on the model: on some models W04 is a fault (output cut, red LED solid), on others a warning (red LED flashing, unit keeps running). Check the card for your model on this page.
How do I clear or fix error W04?: Check whether the input is overvoltage or overfrequency. The exact steps for each affected model are listed on this page.

Related error codes

Other codes on the IVEM8048-II

All IVEM8048-II codes

Other codes on the T-REX-50KHP3G01

All T-REX-50KHP3G01 codes

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

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