436 on a Fronius International GmbH Fronius SnapINverter: Functional incompatibility (PC boards not compatible, e.g. after board replacement)
Short answer
On a Fronius International GmbH inverter, 436 means: Functional incompatibility (PC boards not compatible, e.g. after board replacement). The inverter stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: Functional incompatibility (PC boards not compatible, e.g. after board replacement).
Part involved: firmware/settings.
When it shows: Class 4 status code.
Likely causes:
- Update inverter firmware; if displayed all the time notify Fronius-trained service engineer.
Is it safe?
| Does the inverter stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The inverter stops until the fault clears or is reset.
Resetting itself: unknown.
Manual reset: See engineer checks.
What you can check
- Read the state code on the inverter display or in Fronius Solar.web and note date/time for your installer.
- Contact your installer.
What the engineer will check
- Firmware update; check settings; Fronius Service.
Who to ask for: Fronius-trained PV installer / Fronius Service Partner.
Certification: Qualified electrician (BS 7671; MCS-certified PV installer for work on the PV array/DC side).
What you might notice
Sources
- Fronius Primo 3.0-1 - 8.2-1 Operating Instructions (HTML) ↗ · 42,0410,2165 online edition · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026