If the inverter reports a fault, this is usually no reason to panic – many errors are temporary and clear themselves. What you can safely do: read and note down the message on the display or in the app, check the yield. What you should not do: handle the electronics. If the fault remains or returns, it belongs in specialist hands. (As of: July 2026)
Key points in brief
- Not every error message is a defect – many faults are temporary and disappear by themselves.
- Your contribution: read and note down the message, keep an eye on the yield – do not work on the electrics.
- Recurring or lasting faults and yield loss belong to the specialist company.
- Prerequisite for noticing faults early: an established monitoring with notification.
- If faults accumulate with an older device, replacement can be the more sensible solution instead of repair.
The inverter reports an error – what now?
First: take a deep breath. The inverter is the brain and the guardian of the system – that it reports errors is initially exactly its task, not an alarm for doom. Many messages concern temporary conditions: a brief grid fluctuation, a protective shutdown, a condition that normalises itself again. The device often clears such faults on its own, and the system continues running as if nothing had happened.
The right first step is therefore not actionism, but information: What exactly is the device reporting? The message is on the display of the inverter or in the monitoring app, usually as an error code or plain text. Reading and noting down this exact wording is the most valuable thing you can do – it is the basis for everything else, whether self-all-clear or call to the specialist company.
What you may check yourself – and what not
The same iron boundary applies here as with the whole system: Observe yes, handle the technology no.
You may safely do this:
- Read and note the error message – code, text, time. A photo of the display helps the specialist company.
- Check the yield: Is production continuing or stopped? The annual and previous day comparison in the monitoring shows whether the fault has consequences.
- Observe whether the message disappears by itself or stays – that is the crucial distinction.
You should not do this:
- Handle the electrics or the device, open covers, check cables. The inverter works with dangerous voltages – this is exclusively a matter for the specialist company.
- Climb onto the roof to «have a look». Everything on the roof belongs in professional hands.
A controlled restart according to manufacturer instructions – for example via the app – is the exception that some devices provide; beyond that, self-help ends. This limit is not paternalism, but safety: Amateur work is dangerous on a device that carries DC and AC voltage.
Frequent faults and what lies behind them
Without diving into the error codes of individual manufacturers – they are in their manual – faults can be roughly classified:
| Type of fault | Typical meaning | Your step |
|---|---|---|
| temporary grid message | brief grid fluctuation, protective shutdown | observe – usually self-cleared |
| recurring message | a condition occurs repeatedly | note down, inform specialist company |
| permanent fault / device off | error does not fix itself, production stands still | contact specialist company |
| yield loss without clear message | cause unclear – device, string, shading | specialist company checks |
Simplified overview, as of: July 2026. The exact meaning is in the manufacturer's manual; in case of doubt, the specialist company clarifies.
The distinction between a fault and creeping yield loss is important. The device reports an acute fault; a slowly dropping yield, on the other hand, only shows up in the annual comparison and often has other causes than the inverter – growing shading, for example. And a sudden drop without weather explanation points to a component, not normal, minimal module ageing.
When does the fault become a case for replacing?
Not every fault means the end of the device – most are repairable or temporary. But there is a point where the question shifts: from «fix» to «replace».
This point is reached when faults accumulate in a device that already has many years under its belt anyway. The inverter is the wear part of the system with around 10 to 15 years lifespan – if a device of this age acts up repeatedly, the planned replacement is often the more peaceful and economical solution than repeated repair. This trade-off – patch or exchange – is made by the specialist company based on age, condition and accumulation of faults. For a young device, repair almost always pays off; for an old one that accumulates errors, the calculation tips towards replacement.
In order to be able to judge this progression at all, one needs what belongs to good operation anyway: an established monitoring that reports faults, and an eye that reads the messages. Whoever has this recognises the pattern early and acts in an orderly manner. Whoever never looks only finds out about the problem when the electricity bill reveals it.
The most frequent fault enquiry that reaches us is resolved on the phone: The inverter has thrown a message, the customer is worried – and usually it turns out that the system has long since been producing again because the fault cleared itself. We then ask first for the wording of the message and the yield: Is it running again? Often yes. What we explain again and again: Please do not handle the device or the electrics yourself – that is the one point where a harmless message can turn into a dangerous situation. It gets serious when a fault recurs or remains and production slumps; then we come by. And if a ten, twelve-year-old device starts to act up regularly, we talk openly about replacement instead of the third repair. The customer takes care of reading the message, we take care of the screwing – this division of labour has proven itself over years.
Frequently asked questions
My inverter shows an error – is the solar system broken?
Mostly not. Many messages concern temporary conditions like short grid fluctuations and clear themselves. Read and note down the message and check whether production continues. If the fault remains or returns, inform the specialist company – you should not work on the electrics yourself.
What can I do myself in the event of an inverter fault?
Safe is: read and note the error message (a photo helps), check the yield and observe whether the fault disappears by itself. Some devices allow a controlled restart via the app according to instructions. What you should not do: open covers, handle cables or climb onto the roof.
When do I have to call the specialist company?
If a fault remains or returns and production slumps, or if the yield fails without a clear message. Even if you are unsure, the call is right – with the noted error code, the specialist company can often classify how urgent it is on the phone.
Why do I not see some faults at all?
Because they need a configured notification. An inverter only reports faults via app or email if the function is activated and the messages arrive. That is why setting up the monitoring is part of the commissioning – a fault message that no one receives is of no use.
Repair fault or replace inverter?
For a young device, a repair is almost always worthwhile. If, on the other hand, faults accumulate in an inverter that has been running for ten years or more, replacement is often the quieter and more economical solution – the inverter is the wear part of the system. The specialist company makes this assessment based on age and condition.
Free initial consultation
Inverter fault – we classify it.
Note down the message, we will clarify the rest: With the error code, we can tell you whether it is harmless, needs a repair or replacement is due – without you having to touch the electrics yourself.
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Sources: Manufacturer documentation (inverters, fault and error codes); EnergieSchweiz; empirical values from the service and installation practice of ecoEn GmbH, Zurich region.
Last updated: 9 July 2026 · Author: ecoEn editorial team
