Fronius inverter warranty review

We read Fronius’s warranty so you don’t have to

Let’s face it – warranties aren’t the easiest (or most gripping) documents to read. There are often a lot of details and fine print included that can be hard to digest, leaving many to wonder: what does the warranty actually cover? Am I vulnerable? Anything I might be missing?

To make it as easy as possible, we’ve read warranty documents for the top inverter equipment manufacturers–and talked to them to confirm what is and isn’t included–and plan to point out the most important aspects of each in a series of articles. In this article, we’ll explain everything you need to know about the inverter warranty from an Austrian company that has been around for almost 80 years: Fronius.

This is an unbiased review: EnergySage is not paid to review brands or products, nor do we earn money from affiliate advertising in this article. The content of this blog is based on research and information available at the time of writing. Learn more about our mission and how we make money as a company.

Highlights of Fronius’s warranty

  • Fronius provides a baseline 10-year warranty for their string inverters
  • Fronius inverters have a built-in algorithm – the Dynamic Peak Manager – which they claim reduces the need for power optimizers, lowering the number of warrantied components in your system 
  • Labor and shipping are covered for most Fronius components, including their inverters – and your inverters can easily be repaired at your property 
  • You can extend your Fronius inverter warranty to 15 or 20 years for a fee and can choose whether it will cover labor and shipping (for a higher cost) or just materials. 

Visit the EnergySage Marketplace to compare solar options from local installers.

Quick overview: Fronius’s history and warranty

Founded in Austria in 1945, Fronius started out as an electrical company developing battery charging systems. In 2002, Fronius entered the U.S. solar industry and now offers high-performance string inverters. Many string inverters in residential solar systems are installed with module level power electronics (MLPEs) – AKA power optimizers – which allow you to monitor the power output of each individual panel in your system and maximize your system’s output when there’s partial shading. However, instead of MLPEs, Fronius offers a different type of shade management solution: the Dynamic Peak Manager. The Dynamic Peak Manager is an algorithm that’s integrated into the inverter itself and maximizes the output of your solar system – even when there’s shading.

Solar inverters typically last 10 to 20 years – so, given that solar systems generally last 25+ years, you can expect to replace your inverters at least once during your system’s lifetime. Fortunately, Fronius offers a warranty that will help protect you if your inverter experiences any premature issues. You can also extend your Fronius warranty for a cost if you’re looking for added protection.

Fronius warranty at a glance

CategoryFronius coverageIndustry standard
Product (inverter)10 years10 years for string inverters, 25 years for microinverters
Product (power optimizer equipment – for string inverters only)Not applicable because of Dynamic Peak Manager25 years
Product (communication equipment)10 years5 years
Labor costsYes (for some components)No
Shipping of partsYes (for some components)Yes
TransferabilityYes, automatically and no transfer feeTransfer fee
Extended warranty offeringYes, up to 15 or 20 years for inverter and communication equipment and up to 10 years for Rapid Shutdown BoxNo

Product warranty

Also known as a materials warranty, an inverter product warranty covers the integrity of the equipment itself. If your solar inverter has a defect, mechanical issue, or experiences unreasonable wear and tear, that’s where your product warranty comes into play.

Fronius offers three separate product warranties for a solar system with its inverter technologies: one for the string inverter itself, one for the Rapid Shutdown Box, and another for the Smart Meter. The Fronius Datamanager – which provides wireless communication between the inverter and your monitoring platform – is covered by the same warranty period as your string inverters. The inverter has a baseline product warranty of 10 years whereas the Rapid Shutdown Box and Smart Meter (which is an optional product) are both warrantied for 5 years. 

Inverter replacement: what happens if your product is no longer available?

Let’s say you have a solar inverter that dies after nine years – inverter technology continues to advance, and by then, Fronius may have a brand new product stock. Will they be able to replace your broken inverter?

Should this happen to you, Fronius will offer a replacement with a refurbished product: either of the same product line that you currently have or of a new product that’s compatible with your system. It’s important to note that Fronius keeps spare parts of their products in their inventory long after a product line has been discontinued, adding an extra level of protection for your system. 

Does Fronius offer extended warranties?

Need more protection for peace of mind? Many solar inverter companies offer extended warranties for their products. Depending on the company and the product, an extended warranty may come at an extra cost, or only be available for certain installers who have been certified and endorsed by the manufacturer.

Fronius offers two extended warranty options for their string inverters: the Warranty Extension and the Warranty Extension Plus. Both extensions offer either 15 or 20 years of protection (depending on which you choose) for a fee and also cover the Fronius Datamanager. The difference between the two plans is that the Warranty Extension Plus covers shipping and labor in addition to the products themselves, and the Warranty Extension only covers the products. 

The warranty for the Rapid Shutdown Box can also be extended under the Warranty Extension for up to 10 years, but the warranty for the Smart Meter can’t be extended. If you’re looking to extend your Fronius warranty, you’ll have to purchase the extension through your installer within 30 months of your product’s shipment from the Fronius factory.


More often than not, solar installers are the sole party responsible for providing workmanship–or labor–warranties for your solar installation – they’re performing the actual installation work, after all! However, it’s becoming increasingly common for manufacturers to offer an extra safeguard by tacking on their own workmanship warranty coverage. When applicable, it’s typically only an option if you work with specific installers in a manufacturer’s certified network.

Fronius does not currently offer a workmanship warranty to their customers.

How to make a warranty claim with Fronius: shipping & labor costs

If you experience any defects or performance issues with your equipment, Fronius will be there to help.

To start, if you notice an issue with your inverter, your first phone call should be to your original installer: having designed and installed your system, they are the most equipped to diagnose (and fix!) any potential issue. If you can’t get in touch with your installer, or they’ve gone out of business, Fonius can connect you with a Fronius Authorized Installer to carry out the repair or replacement.

If you start experiencing issues with your inverter during your warranty period, Fronius will first see if the installer can troubleshoot or repair your existing equipment in the field. Fronius’ service program is centered around field-serviceability – meaning for every Fronius inverter, they have spare part kits, allowing certified installers to replace any broken components right at your home with only one truck roll. If need be, they also have a repair center in the United States, where inverters can quickly be repaired. 

If they determine that a replacement is necessary, Fronius will send you a new replacement product if the failure occurs within the first 90 days of installation. After 90 days, Fronius will send you a refurbished product, instead of a new one. In order to process a warranty claim, Fronius has to validate the product’s issue or malfunction, and they also have to have received the purchase invoice, product serial number, and proof of warranty purchase. If the remaining warranty period is less than one year, you will automatically receive a full year for the remaining warranty period for the replacement device or component.

When it comes time for any repairs or replacements, there are two additional warranty considerations you’ll want to keep in mind: labor and shipping costs.

Labor costs for diagnostics, repairs or replacements

Many manufacturers cover replacement parts at no extra cost, but don’t pay for the labor costs necessary to re-install that equipment. Fortunately, Fronius is not one of those companies! The Fronius Warranty Plus applies to their string inverters, Rapid Shutdown Box, and Datamanger, and covers labor costs for removing and installing replacement parts or devices as long as the work is conducted by a Fronius-authorized installer. 

Labor is not covered for the Smart Meter warranty, or for the Warranty Extension (but is covered for the Warranty Extension Plus).

Shipping of parts

Similarly, not all equipment manufacturers will pay the costs to get equipment to you – but fortunately Fronius isn’t one of them. Just like with labor, if your product is covered by the Fronius Warranty Plus or Warranty Extension Plus, you can expect shipping to be covered by Fronius. 

Comparing product and power warranty terms: the EnergySage Buyer’s Guide

What are some of the most popular Fronius products on the market today? Using the EnergySage Buyer’s Guide, you can compare the warranties, performance, and aesthetics of top solar inverters. There’s a lot in there, so we recommend using the filter and sorting functionalities to find the right inverter for you.

Limitations and exceptions

Every warranty comes with limitations and exceptions, including Fronius’. These limitations aren’t meant to make it difficult for you or other customers to take advantage of their offering; at the end of the day, they simply need to protect themselves from unreasonable claims. 

Here are a few things that aren’t covered in your Fronius warranty:

  • Damage as a result of misuse, abuse, accident, negligence or failure to maintain their products
  • Any damage from power surges, lightning, fire, flood, pest damage, accident, work performed on the Warranty Product by a third party not authorized by Fronius
  • Cosmetic damages 
  • Any product which has been disassembled and rebuilt, excluding refurbished units which are provided by Fronius under warranty terms.
  • Faults caused by another component in your solar system

Other warranty considerations, and how Fronius stacks up

  • Transferability: As long as your equipment remains in place, your Fronius warranty will automatically transfer to new owners of your system at no cost (and without any paperwork on your end).
  • Bankability: Fronius positions themselves as being “a stable family-run business with over 25 years of experience in the solar sector.” 
  • Escrows/insurance policies: Fronius does not have insurance policies or an escrow that ensures their warranties will be upheld if they were to go out of business. However, Fronius has three different business units with diversity in product offerings, allowing you to feel confident in the counterparty that supports your warranty.
  • Eligibility: Some manufacturers require customers to permanently connect to their monitoring system in order for their warranty to be valid – but Fronius is not one of these companies. While they encourage customers to connect their systems to their monitoring platform and conduct software updates, this is not required for their warranty to be upheld. 
  • Customer reviews: Another critical aspect of understanding a manufacturer’s warranty offering is investigating how their customers feel about their equipment and the services that they provide. Any warranty can look promising on paper, but how the installer or manufacturer performs when honoring their warranty is also critically important. If you are interested in reading Fronius’s reviews, you can do so here.

The best way to compare solar inverter options – warranties and all!

The key to finding the right solar panel system for your home is comparing multiple quotes from solar installers. Using the EnergySage Marketplace, you can find local solar installers near you, and make easy side-by-side comparisons of all your solar options, including equipment. By shopping around first, you can find the right option at the right price. If you have a preference for one type of equipment over another–Fronius or otherwise–simply note it in your account when you sign up so installers can quote you accordingly.