Solar Panel Warranty Claims: How the Process Works

Understanding solar warranties

Solar equipment comes with two types of warranty:

Product warranty (manufacturing defects)

Covers hardware faults — the panel stops working, the inverter fails, a battery cell goes bad. This is your standard warranty against defective products.

Typical durations:

• Solar panels: 12–25 years (trend is towards 25)
• Inverters: 5–12 years (GivEnergy offers 12; most others offer 10)
• Batteries: 10–15 years
• Optimisers/microinverters: 15–25 years

Performance warranty (panels only)

Solar panel manufacturers guarantee a minimum power output over time. A typical performance warranty guarantees:

• At least 97.5% of rated output in year 1
• Degradation no more than 0.4–0.55% per year thereafter
• At least 84–87% of rated output at year 25 or 30

If your panel's output drops below the warranted level (and it's not due to shading, dirt, or damage), you have a performance warranty claim.

When you might need to claim

Panel product warranty

• Panel physically cracked (not from external impact)
• Junction box failure (water ingress, burnt connectors)
• Delamination (layers separating, visible bubbles or discolouration)
• Hot spots (localised overheating visible on thermal camera)
• Complete panel failure (no output despite correct wiring)

Panel performance warranty

• Measured output significantly below the warranted degradation curve
• One panel producing notably less than identical panels in the same string (possible defect)

Inverter warranty

• Complete failure (no operation, error codes, won't turn on)
• Reduced output capacity
• Persistent error codes not resolved by firmware updates
• Fan failure or overheating shutdowns
• Display or communication module failure

Battery warranty

• Capacity fallen below warranted minimum (e.g., below 60% of original at year 10)
• Battery not holding charge
• BMS (battery management system) failure
• Cell failure causing the whole pack to go offline

The claims process

Step 1: Document the issue

Before contacting anyone:

• Screenshot your monitoring data showing the problem (reduced output, error codes, system offline)
• Take photos of any visible damage or error messages on the unit
• Note the dates when the issue started
• Record model numbers and serial numbers of the affected equipment

Step 2: Contact your installer

Your installer is your first point of contact, not the manufacturer. A good installer will:

• Diagnose the issue (it might be a wiring problem, not a product fault)
• Determine whether it's a warranty claim or a maintenance issue
• Contact the manufacturer on your behalf
• Handle the replacement or repair
• Arrange any scaffolding or access needed

Most MCS-registered installers include a workmanship warranty (typically 2–5 years) covering the installation itself — separate from the manufacturer's product warranty.

Step 3: If your installer can't help

If your installer has closed down, isn't responsive, or their workmanship warranty has expired:

• Contact the manufacturer directly. All major panel and inverter brands have UK support channels. You'll need your proof of purchase, installation date, and serial numbers.
• The manufacturer will assess the claim — often remotely first (via monitoring data), then on-site if needed.
• Under the warranty, the manufacturer provides a replacement product. However, they typically don't cover labour costs for removal and reinstallation. This is a significant gap — getting a faulty panel replaced might cost £200–£400 in scaffolding and labour, even though the replacement panel is free.

Step 4: If the manufacturer is difficult

If a manufacturer rejects your claim or is unresponsive:

• Check your consumer rights. Under the Consumer Rights Act 2015, goods must be of satisfactory quality and fit for purpose. This applies regardless of manufacturer warranty.
• Your contract is with the installer (or retailer), not the manufacturer. If the goods were faulty at delivery, the installer is legally responsible.
• Contact Citizens Advice or Trading Standards if you can't resolve the dispute.
• MCS registered installers are bound by the MCS consumer code, which includes a dispute resolution process.

LONGi Hi-MO X6 450W

£85

watt peak

450

efficiency pct

23

dimensions mm

1722 x 1134 x 30

weight kg

21.3

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Common reasons claims are rejected

External damage

Warranties don't cover damage from external causes — fallen branches, hailstones, accidental impact during other works, or animal damage. This is what your home insurance should cover (make sure your policy includes solar panels).

Improper installation

If the manufacturer determines that the fault was caused by incorrect installation (wrong wiring, inadequate ventilation, improper mounting), they may reject the warranty claim. This is why using an MCS-certified installer matters — their workmanship warranty should cover installation errors, and MCS membership provides a dispute resolution path.

Unauthorised modifications

If you or a third party has modified the system — changed the wiring, replaced components, or added equipment without following the manufacturer's guidelines — the warranty may be voided.

Normal wear and tear

Slight output degradation within the warranted range isn't a warranty claim. Panels naturally lose 0.3–0.5% per year. This is expected and warrantied — it's only a claim if degradation exceeds the warranted rate.

Environmental factors

Corrosion from coastal salt air, UV degradation beyond normal parameters, or damage from extreme weather events may or may not be covered depending on the specific warranty terms.

JA Solar JAM54D41 450W N-type TOPCon

£82

watt peak

450

efficiency pct

22.8

dimensions mm

1722 x 1134 x 30

weight kg

21.5

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The installer insolvency problem

The UK solar industry has seen installer businesses close down, leaving customers without their first point of contact for warranty support. If this happens to you:

1. Your manufacturer warranties remain valid — they're between you and the manufacturer, not the installer
2. The MCS Installation Database holds your system's registration, which can help verify your installation for warranty purposes
3. RECC (Renewable Energy Consumer Code) provides a dispute resolution service and insurance-backed guarantees for member installers
4. Find a new local installer to handle the physical work — they can often manage the warranty claim process with the manufacturer on your behalf (for a fee)

Practical tips

• Register your warranties within the required timeframe after installation
• Keep your monitoring system online — the data history helps substantiate claims
• Get an annual inspection from a qualified electrician (keeps you aware of issues and demonstrates diligent maintenance)
• Don't attempt DIY repairs on faulty panels or inverters — this voids the warranty and is potentially dangerous
• Insure your system through your home contents or buildings insurance (notify your insurer that you have solar panels)

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