What warranties should a NZ solar install include?

A solar install in New Zealand comes with more than one warranty, and they are not interchangeable. The panel maker warrants the module. A performance warranty says how much output the maker still stands behind after a set number of years. The inverter maker warrants the inverter, usually for fewer years than the panels. The installer warrants the workmanship. Your quote should state each term in years, in writing, before you pay a deposit.

Verbal we warranty everything for 25 years is not a term. Ask which document, which company, and what you must do to claim.

Panels

Product warranties on current residential panels are commonly marketed around 25 years. That is a market pattern, not a law, and the certificate in the box is the one that counts. Read what is excluded: transport damage, broken glass, incorrect mounting, and unauthorised modification show up often.

A performance warranty is separate. Makers publish a remaining output percentage at a later year, often out around year 25. Read the percentage and the test conditions. Do not assume every brand promises the same curve. If the quote does not attach the warranty PDF, ask for it before you compare brands.

Serial numbers are how a claim starts. Photograph them at install, or insist the handover pack lists them. A roof you cannot safely climb later is a poor place to be hunting for a label. Ask the installer to email the serial list as a spreadsheet or a photo set the week of commissioning, and save it next to the invoice.

Inverters and batteries

Inverter warranties are often in a band of about 5 to 12 years, sometimes with a paid extension. The inverter is the part most likely to need replacement inside the life of the panels. Put that replacement cost in your long view even when the simple payback on the install still looks acceptable.

A microinverter or optimiser has its own warranty, sometimes longer than a central inverter, with a different replacement job because the unit is on the roof. Ask who pays labour if the part is covered and the access is not.

Battery warranties are usually a mix of years and energy throughput or cycles. Two products with the same headline years can differ in usable kilowatt-hours and in what voids the cover. The battery guide is the buying context: https://homesolarinstallation.co.nz/blog/solar-battery-storage-nz/

Workmanship

Workmanship is the installer's promise about brackets, flashings, cabling, labelling and leaks from their penetrations. It is often shorter than the panel product warranty. Ten years is a figure you will see. So are shorter terms. The number on your contract is the number.

If a later contractor adds panels or moves brackets, ask whether the original workmanship warranty survives. Get the answer in an email. The add-on guide is here: https://homesolarinstallation.co.nz/blog/add-solar-panels-later-nz/

A company can close. Ask whether the workmanship promise sits with a named insurer or only with the trading company. Product warranties with the manufacturer can outlive the installer. Workmanship often does not. Keep the manufacturer's documents in your own file, not only on the installer's portal.

A 25-year panel brochure does not pay for the electrician's labour, the scaffold, or a new inverter. When you compare two quotes, write four numbers: panel product years, the year-25 performance percentage, inverter years, and workmanship years. If one quote leaves a number blank, it is not the longer warranty. It is an unfinished quote.

What a claim needs

Keep the quote, the compliance certificate, the approval, the warranty PDFs, the serials, and a short note of the install date. When output falls, add screenshots and the weather. A claim that starts with I think it was about five years ago is slower than a claim with a serial and a date.

The Electrical Safety Certificate is not a warranty, but you will be asked for it. The first-month list is when you gather this: https://homesolarinstallation.co.nz/blog/first-month-after-solar-nz/

Insurance is separate again. A warranty replaces a defective product or repairs bad work. An insurance policy responds to insured events such as storm, on the terms you agreed. Tell the insurer the panels are there. The insurance guide on this site covers that call.

Comparing quotes on warranty, not on adjectives

Line the years up beside the price and the kilowatts. A cheaper array with a short workmanship term and an unnamed inverter warranty can cost more at the first call-out. A dearer array with long paper you have read can still be a poor buy if the roof was the wrong size. Warranty does not rescue a bad design.

The installer checklist is the wider comparison: https://homesolarinstallation.co.nz/blog/choose-solar-installer-nz/ EECA's price bands are the cost context, not a warranty: https://homesolarinstallation.co.nz/blog/solar-panel-cost-nz/

Questions worth sending

Ask these in one email and keep the reply with the contract.

• Panel product years, performance percentage at the end year, and the PDF
• Inverter years, whether labour is included, and the extension price
• Workmanship years, and what happens if your company closes
• Who I phone in year eight, and the serial list
• Whether a later battery or extra panels voids any of the three warranties

Paperwork for these suburbs

Warranty terms do not change by suburb, and the file still needs to exist for houses in Algies Bay, Arkles Bay, Army Bay, Big Omaha, Coatesville, Dairy Flat, Dome Forest, Dome Valley, Glorit, Gulf Harbour, Hatfields Beach, Helensville, Huapai, Kaukapakapa, Kawau Island, Kumeu, Leigh, Matakana, Muriwai, Omaha, Orewa, Puhoi, Riverhead, Snells Beach, South Head, Waimauku, Warkworth, Wellsford, Bayswater, Belmont, Campbells Bay, Castor Bay, Devonport, Forrest Hill, Hauraki, Milford, Narrow Neck, Stanley Point, Sunnynook and Takapuna. Salt exposure at Muriwai, South Head, Leigh, Hatfields Beach, Gulf Harbour, Orewa and Kawau Island is a reason to read corrosion exclusions in the mounting and inverter warranty, and to photograph fixings. A Takapuna, Milford or Devonport roof has the same need for serial numbers. Distance from Wellsford, Glorit or Kawau Island makes a missing document more annoying, because a second visit is a longer trip.

Home Solar Installation NZ can introduce a local partner. The form is free and there is no obligation. Ask for the warranty years in the quote, not after you have paid. EECA's public cost page is https://www.eeca.govt.nz/for-homes/solar-for-homes/solar-costs-and-savings/