Solar Why is my solar inverter showing a red light or error?
A red light or error means the inverter has detected a condition; note the code and call a licensed installer, and do not open the unit.
A red light or error means your inverter has detected a condition it does not like, such as grid voltage out of range, an insulation fault or a waiting period after a restart. Codes differ by brand. Photograph the display, note the code and time, keep clear of the unit and contact a licensed installer.
What are the common causes?
Installers and manufacturers describe a few usual causes. Some are harmless and pass by themselves, and others point to a real fault.
- Grid voltage or frequency problems. The inverter stops when the grid supply falls outside its limits, and usually starts again when it recovers.
- A waiting period. After an outage or restart, an inverter checks the grid before it exports again, so a light or message during that time can be normal.
- An isolation fault. The inverter has detected that electricity may be leaking where it should not. This needs a professional.
- Equipment faults. Panels, cabling, the inverter itself or communication problems can all trigger an error.
The meaning of a coloured light or a code is specific to each brand and model, which is why the code and model matter more than the colour.
When is it serious?
An isolation fault, a fault that keeps coming back, or any sign of heat, noise, water or damage should be treated as serious. Repeated faults mean something is still wrong, even if the system seems to recover.
Why shouldn't I open the inverter or try a fix?
An inverter handles both the direct current coming from your panels and the alternating current from the grid. The panel side can remain live in daylight even when the display is dark. The inside of the unit and the cabling are work for a licensed person.
Switching equipment on and off in the hope that it clears the error can also hide useful information or make a fault worse. Your installer or manufacturer will advise whether any restart is appropriate for your model.
What to note for the installer
The code or message
Photograph the display or your monitoring app. Write down any code exactly as shown.
The light colour and pattern
Note what colour the light is, and whether it is steady or flashing.
When it happened
Note the time, the weather, and whether there had been an outage or storm.
Make, model and serial number
Photograph the label on the inverter without touching or opening anything, and find your installation paperwork.
Whether it repeats
Keep a note of how often the error appears and whether other things in the house were affected.
What if my system is under warranty?
Your installer or the manufacturer will explain what applies. Tampering with the unit, or having an unlicensed person work on it, can cause problems, so let them make the call. Rental tenants should report the fault to their landlord or property manager.
What will the installer do?
A licensed installer will read the fault history stored in the inverter, inspect the system and, where an isolation fault is suspected, check the condition of the panel-side wiring with proper test equipment. The repair depends on what they find, which could be as simple as a loose or damaged connection or as involved as a failed component. Either way, it is work for a licensed person.
Frequently asked questions
No. It can be a temporary grid issue or a waiting period after a restart. But because codes vary by brand, note the code and ask your installer.
It means the inverter has detected that electricity may be leaking from the solar system. It needs a licensed installer to investigate.
No. Repeated attempts can hide useful information. Note the code and ask your installer what to do.
No. The panel side can be live in daylight even when the display is dark. Only a licensed professional should open it.
The error code, the time, the make, model and serial number from the label, and whether it keeps happening.
Related services: Solar Cleaning, Solar Batteries
Was this helpful?