Our house has a brand new solar system installed in 2018 with 5 years warranty.
Now we have an issue with the inverter and the supplier has sent us an offer over CHF850. When inquired they informed that only the unit replacement is covered under the warranty and customers need to pay the transport, admin and replacement labour costs. Is this normal?
I find it unusual, but not impossible, that the warranty would not include that stuff. If something is under warranty, you shouldn't have to pay to repair/replace it.
If your OH can't find the T's&C's, ask the supplier for the small print where it is stated that this is the case.
You might be able to save some money by offering to collect it yourself and getting somebody else to fit it, or it might trigger a price reduction or warranty extension negotiation.
You'd need to find the contract for the installation. The previous owners might send it. For my "solar system" the guarantee includes the company doing the repair work as well as replacing the broken item, but there's small print to haggle over, eg storm damage or not.
Do you know if the inverter is on the roof or elsewhere, eg a cupboard on the wall outside, or a bank of them next to the fusebox? Either way 850 chuffs is a lot for someone to come along and fit one, it ought to be a quick job (but not if you have one microinverter per panel that happens to sit under the panel and they can't tell which one needs to be fixed and so have to lift panel by panel etyc). "Admin" charges should mean someone taking a spare off the shelf in the depot etc.
I have asked them to check on about the error code and have them suggest the problem. If it is about replacing the converter, I can do it myself as its is located inside the house and looks like a 30 min job.