Solar Warranty Explained: Panels, Inverter and Workmanship

Why one system has several warranties

People often ask how long the warranty on solar is, as if there were one answer. A rooftop system is a collection of components made by different companies, and each has its own warranty. The panels, the inverter, the mounting structure, the cables and the installation work are covered separately, for different periods and under different conditions.

The marketing line of a 25-year warranty usually refers to only one part of the system. Find out which part, what it covers and who honours it, so you can compare quotations fairly and avoid surprises years later.

Product warranty on the panels

The product warranty, also called the materials or manufacturing warranty, covers defects in the panel itself, such as faulty cells, a failing junction box, delamination or frame problems that appear under normal use. Typical periods from reputable manufacturers range from about ten to twelve years, and some premium products offer longer.

Read what the warranty excludes. Most exclude damage from hail, storms, fire, theft, incorrect installation and misuse. They may also require proof of purchase and of proper installation. The product warranty is given by the panel manufacturer, so know the brand, the model and where claims are handled in India.

Performance warranty on the panels

Panels slowly lose a small amount of output every year, a process called degradation. A performance warranty promises that after a stated number of years the panel will still deliver at least a certain percentage of its original rated power. Many manufacturers quote a figure in the range of eighty to ninety percent at the end of twenty-five years, with a small allowed drop in the first year and a gentle decline afterwards.

This is the warranty behind the 25-year claim in advertisements. It is a guarantee about power output, not about the panel being undamaged. To claim it, you generally need to show that the measured output has fallen below the guaranteed level, which usually requires testing by an authorised person.

Inverter warranty

The inverter works hardest, converting electricity all day, and it is the component most likely to need attention first. Warranties are shorter than for panels, often in the range of five to ten years, and some manufacturers offer paid extensions. Ask whether the warranty covers parts only or also labour and transport, and whether a replacement unit is shipped in advance or only after the faulty unit is inspected.

Because you should expect to replace the inverter at least once during the life of the panels, include that cost in your long-term calculation. A cheaper inverter with a short warranty and weak service may cost more over twenty-five years than a better one with strong local support.

Installation workmanship and the structure

The installer's own warranty covers the quality of the work: the mounting structure, fixings, cable routing, connections, earthing and the roof penetrations. Many real-world problems, such as leaks, loose fixings and poor connections, come from workmanship, not from defective panels, so this warranty deserves as much attention as the others.

Because it is given by the installer and not by a large manufacturer, it is only as reliable as the company. Check how long the installer has been in business, whether they have a local office, and whether previous customers have been satisfied. Ask for the workmanship warranty length, what it includes and how to reach the service team.

Who actually honours a claim

The most important practical question is who you call when something fails. In many cases the installer is the first contact and coordinates with the manufacturer on your behalf. If the installer closes or moves, you may have to deal with the manufacturer directly, which is harder if you do not have the paperwork.

Ask the installer in advance how claims are handled, how long the process typically takes and whether they provide a temporary replacement. Choose a brand that has an actual service presence in your region, and note the customer-care number for each component.

• Ask the installer how warranty claims will be handled and who you should call.
• Confirm whether labour and transport are covered or only parts.
• Check whether the manufacturer has a service centre or authorised partner near you.
• Keep invoices, serial numbers and the commissioning report together.

What can void a warranty

Warranties come with conditions, and ignoring them can void your cover. Common conditions include installation by an authorised or competent person, use within the specified electrical limits, regular maintenance such as cleaning, protection from rodents and physical damage, and not altering the system without approval.

Using the wrong cleaning method, such as abrasive tools or harsh chemicals, can scratch the glass and cause a claim to be refused. Adding panels or changing the inverter settings without the installer's advice can also cause trouble. If in doubt, ask before you change anything.

Paperwork to keep for 25 years

You can use a warranty only if you can prove it. Keep a folder, on paper and in digital form, with the quotation, the invoice, payment receipts, warranty cards, serial numbers of panels and inverter, the commissioning certificate and the net metering documents. Store a digital copy somewhere safe, such as an email to yourself, because paper fades and gets lost.

When you sell the property, hand the folder to the new owner. A buyer who sees documented warranties and a generation history is more comfortable, and a transferable warranty adds value to the house.

Red flags in warranty promises

Be wary of offers that sound too generous. A promise of a lifetime warranty, a warranty on the whole system for twenty-five years or a guarantee of zero electricity bills should always be backed by a written document that names the party giving it and states exactly what is covered. If the document is vague, if it says only that the warranty is as per manufacturer norms, or if it cannot be produced before payment, treat that as a warning sign.

A reliable installer is happy to show the manufacturer's warranty documents for the specific models in your quotation, to explain the claim process and to put their own workmanship warranty on paper. If you are asked to pay in full before you have seen any of this, pause and ask again.

• No written warranty before payment.
• Warranty described only in general terms, with no model names.
• Promises that cover everything for the full life of the system.
• No local office or phone number for service.

A short checklist before you pay

Before you sign the final agreement, run through these quick checks, which take ten minutes. Compare the answers across your quotations: the best warranty package often comes from an installer who costs slightly more but is far more reliable.

• Do I have the warranty length for panels, inverter and workmanship in writing?
• Do I know the brand and model of each component?
• Do I know who to call for service and where their nearest centre is?
• Are the conditions that could void the warranty clear to me?
• Have I received a copy of the commissioning report and serial numbers?