Warning What does this mean?

Your system is down or running degraded, but this is not an immediate safety danger. Work through the safe steps below.

SolarEdge Inverter Fan Failure: Meaning, Causes & Safe Fix

One of the inverter's cooling fans isn't working. The system can keep running but may overheat and derate — try one power cycle, and if the fan doesn't restart, have your installer replace it.

What should I do first?

Two quick questions — we'll point you to the right starting point.

Is this code still showing on your inverter's display?

What this code means

SolarEdge three-phase inverters monitor their cooling fans and raise a 'Fan # Failure' system warning (codes 8x66–8x69, 8x6A–8x6F on CPU v3.19xx firmware) when one stops working. It appears as a warning rather than a hard error, but without proper cooling the inverter is likely to hit Temperature Too High derating on warm days.

What is this downtime costing you?

Rough estimate while your system isn't producing. Adjust the numbers to match your setup.

System size (kW) Peak sun hours / day Electricity rate ($/kWh)

–per day

–per week

–per 30 days

≈ – kWh of lost production per day.

Estimate only — assumes ~80% real-world output vs. nameplate. Actual losses depend on weather, shading, panel direction, and your tariff.

Common causes

The fan is jammed by debris, dust build-up, or insects (most common)
The fan motor has worn out with age
A loose internal fan connector (technician-only check)
A firmware glitch failing to detect a working fan

Safe steps to try

Work top to bottom, ticking off each step as you complete it. 0 of 5 done.

Perform one full power cycle — fans often restart after the inverter reboots (P/1/0 to OFF, wait, DC disconnect OFF, AC breaker OFF, wait 2 minutes, reverse the order).
Visually inspect the fan area from outside for visible debris or blockages. Do NOT open the inverter or poke anything into the fan.
After restarting, listen/look for whether the fan spins during operation.
Check whether a Temperature Too High warning appears alongside — that confirms cooling is compromised.
Note the warning code and contact your installer if the fan stays dead.

Is your inverter still under warranty?

Before paying for a repair, check — your installer may fix this free.

Brand Year installed

Based on typical standard warranty terms — always confirm with your warranty card or installer paperwork, as terms vary by model, region, and purchase date.

When to call an electrician

If the fan does not restart after a power cycle, or a Temperature Too High warning appears with it, contact your installer. SolarEdge offers fan replacement kits, but fitting one is an installer job — the manual says 'Clean or replace the fan' as the remedy, performed by qualified personnel.

Frequently asked questions

Can my solar still work with a failed fan?

Usually yes, but the inverter will derate (reduce output) sooner on warm days to protect itself. Get the fan fixed rather than running derated for months.

Can I replace the inverter fan myself?

No — the fan is inside the unit and replacement means opening it, which only a qualified technician should do. Replacement kits are available from SolarEdge through installers.

How do I know which fan failed?

The warning identifies the fan number (Fan # Failure). Pass the exact code to your installer so they bring the right replacement kit.

Need a professional?

This fault may need professional diagnosis. Contact a qualified solar electrician in your area.

Sources: meaning and troubleshooting verified against the manufacturer's documentation — Troubleshooting SolarEdge Systems, Addendum (Europe & APAC), MAN-01-00333-1.1 — System Warnings section ('1-4, 6-7 | 8x66-8x69, 8x6A-8x6F | Fan # Failure | Clean or replace the fan').