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GoodWe Fan Failure

Updated June 2026 · Reviewed for technical accuracy · ~2 min read

Fan Failure (error 16 or 20) means your GoodWe detected that a cooling fan is not spinning the way it should. To stay safe the inverter may derate, dropping its output so it does not overheat. The good news is that the most common cause is simply dust or debris jamming the fan, which you can often clear from the outside.

What usually causes it

  • Dust, leaves or insects jamming the fan or blocking the grille, the most common cause.
  • An obstruction right behind or below the unit restricting airflow.
  • A worn or aged fan that no longer spins freely.
  • A fault in the fan or its sensing circuit, if cleaning does not help.

How to handle it safely

Power down before you touch it Only clean the outside grille. Do not open the inverter, the fan replacement itself is an installer job.
  1. Power the inverter down. Switch off the AC and the DC isolator so the fan is not live while you look.
  2. Inspect and gently clean the fan grille. Clear dust, cobwebs, leaves or insects from the external vent with a soft brush or low-pressure air.
  3. Clear space around the unit so air can move freely.
  4. Restart and check for airflow. Near full load on a warm day, feel or listen for the fan. If it still does not run, the fan needs replacing.
  5. If it does not spin, contact your installer or GoodWe for a fan replacement.

Quick decision flowchart

Fan Failure appears
↓ power down, clean the grille, restart
✅ Fan spins, fault clears → it was debris. Keep the vents clean.
❌ Fan still does not run → the fan or its circuit needs replacing.
↓
Book an installer or GoodWe service for the fan replacement.

Related GoodWe codes

Over Temperature Relay Check Failure Vac Failure, Grid voltage

FAQ

Can I keep running the inverter with a failed fan?

For a short time it will protect itself by derating, but you should not leave it like that. Without proper cooling it will run hotter, lose output on warm days and shorten its own life, and Over Temperature faults often follow. Get the fan sorted promptly.

Can I replace the GoodWe fan myself?

You can safely clean dust from the external fan grille with the unit powered down. Replacing the fan itself means opening the inverter, which carries lethal voltage and should be done by a licensed installer or GoodWe service, not the owner.

Helpful guides

Error codes explained How to safely restart your inverter Inverter overheating

Sources

  • GoodWe inverter user manual and error-message list (Fan Failure / error 16 or 20 = cooling fan not operating correctly; clear obstructions, replace the fan if needed).
  • GoodWe installer documentation.
⚠️ Safety disclaimer. Solar inverters carry lethal DC and AC voltage even when "off". This guide covers external cleaning of the fan grille only. Never open the unit; fan replacement and internal work must be done by a licensed installer or GoodWe support.