We provide service and repairs for existing solar systems in the Zurich region, including systems built by other installers – for example when the original company can no longer be reached or has gone bankrupt. This covers fault diagnosis, repairs, inverter replacement (battery-ready on request) and taking over the monitoring. We tell you the cost of a call-out in advance. We do not complete half-finished installations, and we accept no liability for the previous installer's work. (As of October 2026)
Key points in brief
- We also look after systems we did not build – regardless of the inverter and module brand.
- Typical reasons: an error message, low yield, an inverter that has failed or reached the end of its service life, monitoring offline.
- Manufacturer warranties on modules and inverters continue via the manufacturer, even if the installer no longer exists.
- When the inverter is replaced, the system can be prepared for battery storage at the same time.
- We tell you the cost of the call-out before the appointment; a repair or replacement only follows once you have agreed.
When does your solar system need a service?
Most of the time, a solar system runs unnoticed. It makes itself known when something is wrong: through an error message in the app, a blank display on the inverter or an annual yield well below the previous year's. Often this only becomes apparent when the credit from the utility gets smaller. How to tell a genuine yield shortfall from weather and normal ageing is explained in the article Solar system producing too little.
| Reason | What we do |
|---|---|
| Error message or inverter at a standstill | Diagnosis on site or from the monitoring data, repair or replacement |
| Yield clearly lower than in previous years | Yield comparison, check of inverter, strings and shading |
| Inverter 10 to 15 years old, faults becoming more frequent | Plan the replacement, on request with a hybrid inverter for a later battery |
| Monitoring offline, access unknown | Restore the connection, have access transferred to you via the manufacturer |
| Installer no longer reachable or bankrupt | Inventory, review the documents, take over support |
| Retrofit a battery or wallbox | Check whether the existing system is suitable, and provide a quote |
Overview, as of October 2026. What is needed in an individual case is shown by the diagnosis.
Your installer can no longer be reached – what now?
After the boom years up to 2024, several Swiss solar companies have filed for bankruptcy. In April 2026, SRF documented five cases and around 140 unfinished orders at just one of these companies. For the owners of completed systems, this raises a sober question: who will look after the system in future?
The good news first: the product and performance warranties on modules and inverters are given by the manufacturer, not the installer. They remain valid as long as the manufacturer exists. What in practice falls away with the bankruptcy is the warranty under the contract for work covering the installation. Claims arising from it can be lodged in the bankruptcy proceedings; what comes of them depends on the proceedings. The article Handling a warranty claim correctly explains the three warranties and who is responsible for each (not legal advice).
For operation, this means your system needs a new point of contact who knows the components, can register warranty claims with the manufacturer and comes out when there is a fault. We take on this role. It starts with an inventory: we review the existing documents, inspect the system, have the monitoring access transferred to you via the manufacturer and tell you what is in order and what is not.
There are two things we deliberately do not do. We do not complete half-finished installations, because we neither planned nor supervised the work already carried out. And we accept no liability for the previous installer's work. What we stand behind is what we repair, replace or install ourselves.
Replacing the inverter: the predictable appointment in a system's life
An inverter typically lasts 10 to 15 years, the modules considerably longer. Systems built between 2010 and 2015 are therefore now reaching the age at which replacement is due. The swap itself is usually done in a few hours, without scaffolding: the unit hangs in the basement or plant room, not on the roof. The process and warning signs are described in the article Replacing an inverter, the typical service life in the article How long does an inverter last?.
Replacement becomes interesting if you are thinking about a battery. A hybrid inverter makes the system battery-ready without a second unit being needed later. Since the remuneration for electricity fed into the grid has fallen in many places, many owners of older systems are recalculating: every kilowatt hour consumed on site replaces expensive grid electricity. When retrofitting pays off is shown in the article Retrofitting a home battery.
After the replacement, we issue the safety certificate (SiNa) for the modified installation and, where necessary, register the new unit with the grid operator. The cost depends on the power class and the choice of unit; a flat figure would not be serious. You receive a quote before the replacement.
Is repowering worthwhile for an older system?
Repowering means replacing old modules with more powerful ones. Before the modules reach the end of their life it is rarely worthwhile, because good modules lose only a little output each year. The picture is different if modules are damaged, if the roof is being renovated anyway or if a very old system could deliver considerably more on the same area. We calculate both options for you, continued operation and renewal, and advise against it if the swap does not pay off. Background in the article Repowering: when upgrading pays off.
How a service call works
1. Enquiry: You describe the problem and, if possible, send a photo of the rating plate on the inverter and a screenshot of the error message or the yield curve. 2. Initial assessment: We get back to you, assess the case and tell you the cost of the call-out in advance. 3. Diagnosis: on site or, if access is available, first from the monitoring data. 4. Quote: For a repair, replacement or retrofit, you receive a written quote; work is only carried out once you have agreed. 5. Execution and documentation: repair or replacement, safety certificate for modified installations, documents for your system file.
Any documents you have about the system are helpful: wiring diagram, acceptance report and safety certificate, invoices showing the module and inverter type, Pronovo confirmation and login details for the monitoring. If any of these are missing, that is no obstacle, just a little more work during the inventory. What you can check yourself once a year is shown in the checklist for solar system owners.
Why a licensed electrical specialist?
Work on the electrical side of a solar system, i.e. on the inverter, the cabling and the connection, may only be carried out by companies holding an installation authorisation from the Federal Inspectorate for Heavy Current Installations (ESTI). ecoEn GmbH holds such an authorisation (no. SOB-284349-1, verifiable in the ESTI register), is a member of Swissolar and has been building solar systems in the Zurich region since 2017. We support operation after construction for our own systems as a matter of course; for third-party systems, this support starts with the inventory.
With systems taken over from others, what is most often missing is not a component but the overview: nobody knows exactly which inverter is installed any more, the monitoring access ran via the old installer's account, and the folder with the wiring diagram and acceptance report is incomplete. That is why we start with an inventory rather than a repair. Afterwards it is usually clear whether only a small fix is needed or whether the inverter replacement is due – and whether the opportunity for a battery arises.
Frequently asked questions
Does ecoEn also look after solar systems built by another company?
Yes. We provide service, repairs, inverter replacement and monitoring for systems from other installers in the Zurich region too, regardless of the component brand. It starts with an inventory. We accept no liability for the previous installer's work; we stand behind what we carry out ourselves.
What happens to the warranty if my solar installer goes bankrupt?
Product and performance warranties on modules and inverters are given by the manufacturer and remain valid as long as the manufacturer exists. What falls away in practice is the warranty under the contract for work covering the installation; claims arising from it can be lodged in the bankruptcy proceedings. We register warranty claims with the manufacturer on your behalf. This is not legal advice.
Does ecoEn complete half-finished solar systems?
No. We do not complete half-finished systems from another company, because we neither planned nor supervised the work already carried out. We are, however, happy to look after fully built systems: diagnosis, repairs, inverter replacement and monitoring.
What does a service call for a solar system cost?
That depends on the reason, for example a simple fault diagnosis or an inventory with a review of the documents. We tell you the cost of the call-out before the appointment. For repairs, an inverter replacement or a retrofit, you receive a written quote before any work is carried out.
When should the inverter be replaced?
Typically after 10 to 15 years, or when faults become more frequent and a repair is no longer worthwhile. The monitoring usually shows this early on. If you are considering a battery, replace it with a hybrid inverter and the system becomes battery-ready at the same time.
Can I retrofit a battery to my older system?
In most cases yes, either AC-coupled with its own battery inverter or, when the inverter is replaced, via a hybrid inverter. Which option fits depends on the existing unit, the consumption and the space available. We check this during the inventory.
I can no longer access my system's monitoring. What should I do?
Access often ran via the installer's account. Manufacturers can usually transfer the system to a new service provider or directly to you. We clarify this with the manufacturer and restore the inverter's connection if it has been interrupted.
Free initial consultation
Service request for your solar system
Briefly describe the problem, ideally with a photo of the inverter's rating plate. We get back to you, assess the case and tell you the cost of the call-out in advance – even if your system was built by another company.
Prefer to talk? +41 78 830 83 35
Your photovoltaic system from a specialist company →
Swissolar member and Solarprofi · ESTI installation authorisation (Art. 14 NIV) · in Zurich since 2017 · over 150 systems completed · a personal answer from the specialist company, no call centre
Sources: SRF Kassensturz/Espresso, «Pleitewelle bei Solaranlagen – Kundschaft leidet unter Konkursen in der Solarbranche» (20.4.2026); ESTI, register of installation authorisations (no. SOB-284349-1); practical experience of ecoEn GmbH (Zurich region). As of October 2026.
Last updated: 9 July 2026 · Author: ecoEn editorial team
