California homeowners installed more solar in the last decade than any other state. Most of those systems came with two warranties: one covering physical defects in the panels, and one guaranteeing a minimum level of power output over 25 years. When your system is not performing as promised, knowing which warranty applies, who to contact, and how to document your claim is the difference between a resolved issue and years of lost savings.
This guide is written for homeowners in Southern California, with specific attention to the SCE service territory covering Temecula, Murrieta, Lake Elsinore, and the Inland Empire. The legal framework, utility context, and escalation paths described here apply throughout California.
1The Two Types of Solar Warranties
Every solar panel sold in the United States comes with two distinct warranties. They are often bundled into a single document but cover completely different things. Confusing them is the most common mistake homeowners make when trying to file a claim.
Product Warranty
Also called a materials warranty or equipment warranty. This covers physical defects in the panel itself: manufacturing flaws, broken cells, delamination (layers separating), frame corrosion, and electrical failures inside the panel enclosure. If the panel physically fails, stops producing power due to a component failure, or shows visible structural defects not caused by an external event, this is the warranty that covers it. Standard duration: 12 to 25 years depending on manufacturer and panel tier.
Performance Warranty
Also called a power output warranty or linear performance guarantee. This guarantees that your panels will produce at least a minimum percentage of their original rated wattage over time. It does not require any visible defect. If your panels are producing below the guaranteed threshold, the warranty is triggered purely on output numbers. Standard terms: 80 to 87 percent of original rated output at year 25, with a maximum annual degradation of 0.4 to 0.7 percent per year.
The critical distinction is this: a panel can look completely normal and still be failing its performance warranty. Conversely, a panel with minor cosmetic issues may still be producing above the warranty threshold and therefore not eligible for a claim. You need to understand which warranty applies to your situation before you make the first call.
There is also a third warranty that many homeowners overlook: the workmanship warranty from the installer. This covers problems caused by how the system was installed, not problems with the equipment itself. Improper mounting, incorrect wire sizing, roof penetrations that leak, and substandard electrical connections are all workmanship issues. These are covered by the installer, not the manufacturer, under a separate workmanship warranty that typically lasts 1 to 10 years.
2Standard Warranty Terms in 2026: What the Numbers Actually Mean
The solar industry has converged on fairly standard warranty language, but the specific numbers matter when you are trying to determine whether a claim is valid. Here is what you are actually being promised by leading manufacturers in 2026.
| Manufacturer | Product Warranty | Yr 1 Guarantee | Yr 25 Guarantee |
|---|---|---|---|
| Maxeon (formerly SunPower) | 25 years | 98% | 88.25% |
| REC Group | 25 years | 98% | 86% |
| Panasonic HIT | 25 years | 90.76% | 80.7% |
| LG (legacy systems) | 25 years | 98% | 80.7% |
| Canadian Solar | 12-25 years | 97.5% | 80.7% |
| Jinko Solar | 12 years | 97.5% | 80.7% |
| Q Cells | 25 years | 98% | 86% |
What "98% at Year 1" Actually Means
A 400-watt panel with a 98% first-year guarantee is warranted to produce at least 392 watts after one year. By year 25, with a guarantee of 87%, it must still produce at least 348 watts. If your monitoring data shows consistent output equivalent to less than the guaranteed wattage across the entire array, adjusted for your location's solar irradiance, you have grounds for a performance warranty claim. The key word is "consistent." One underperforming month does not trigger a claim. A sustained pattern does.
3How to Tell If Your System Is Actually Underperforming
The most common reason homeowners think their system is underperforming is that they expected a number and got a different number, without accounting for weather, seasons, or their own energy consumption changes. Before filing any warranty claim, you need to do a disciplined comparison that accounts for these variables.
Step A: Pull Your Proposal Estimate
Your original solar proposal from the installer should include a year-one production estimate in kilowatt-hours (kWh), usually broken down by month. Find this document. If you cannot locate it, your installer or financing company can provide a copy. This is your baseline.
Step B: Export 12 Months of Actual Production Data
Log into your monitoring portal. Enphase Enlighten, SolarEdge monitoring, and most other systems allow you to export monthly production data as a CSV or PDF. Download at least 12 consecutive months. Compare each month's actual production to the estimate in your proposal.
Step C: Apply the 10 Percent Threshold Rule
A single month 5 percent below estimate is noise. A full year averaging 10 percent or more below estimate is a signal. If your annual production is consistently more than 10 percent below the original proposal estimate, you have a documented underperformance situation that warrants a manufacturer inquiry.
Step D: Check for New Shading Sources
New trees, a neighbor's addition, a new fence, or even antenna equipment installed after your solar array can reduce production dramatically. This is not a warranty issue. Walk your property and look at what casts shadows on your panels between 9am and 3pm on a clear day. Temecula's inland valley sun angle means shading from the east or west matters most in summer months.
California's National Renewable Energy Laboratory (NREL) PVWatts calculator lets you enter your exact address and system specs and see what your array should theoretically produce in any given year based on historical solar irradiance data. This is a useful cross-check that manufacturers themselves often use. If your actual production is below what PVWatts calculates AND below your proposal estimate, your case for a warranty claim is strong.
4Step 1: Documenting the Underperformance Before You Call Anyone
How you document your underperformance before making the first call determines how seriously you are taken and how quickly the claim resolves. A homeowner who calls and says "my system seems slow" gets a very different response than one who emails a clear, organized package with timestamped data. Build the package first.
Your Warranty Claim Documentation Package
Once this package is assembled, send it via email to the warranty contact for the manufacturer AND to your installer, keeping copies. Email creates a date-stamped paper trail that a phone call does not. Subject line should include your panel model number, your system address, and the words "warranty claim documentation." Never rely solely on a phone call to initiate a formal warranty claim.
5Step 2: Manufacturer vs Installer - Who Is Responsible for What
This is where most warranty claims stall. Homeowners contact the wrong party, get bounced back and forth, and eventually give up. Understanding the clear division of responsibility prevents this.
Contact the Panel Manufacturer If:
- - Your panels have visible cell damage, discoloration (yellowing or browning), or bubbling encapsulant
- - Individual panels are producing significantly less than identical panels in the same string
- - Your entire array is producing below the manufacturer's guaranteed output percentage after accounting for age and normal degradation
- - You suspect potential-induced degradation (PID) or microcracking from a manufacturing defect
- - The physical frame of the panel has corrosion or structural failure not caused by impact damage
Contact the Installer If:
- - Your roof is leaking at or near the panel mounting points
- - Wiring or conduit installed during the solar job is damaged or improperly routed
- - The system was installed with incorrect string sizing or inverter configuration that limits output from day one
- - Panels were installed at the wrong tilt angle or orientation compared to what was specified in the proposal
- - The monitoring system was set up incorrectly and never reported accurate data
Contact the Inverter Manufacturer Separately
Your inverter (whether a string inverter, power optimizer, or microinverter) has its own warranty, separate from your panel warranty. Enphase microinverters typically carry a 25-year warranty. SolarEdge string inverters with optimizers carry a 12-year warranty on the inverter (extendable to 20 or 25 years) and 25 years on the optimizers. Fronius, SMA, and other brands vary. If the issue is that your inverter is clipping production, throwing error codes, or failing entirely, contact the inverter manufacturer directly.
When both the panel manufacturer and the installer blame each other, hire an independent solar inspector to provide a written assessment of the root cause. That report becomes the deciding document that identifies which warranty applies. We cover this in more detail in the third-party inspection section below.
6Step 3: What a Warranty Inspection Actually Looks Like
Once you file a formal warranty claim with supporting documentation, most manufacturers will initiate an inspection process. Understanding what that looks like prevents surprises and helps you prepare your property.
Remote Data Review (Weeks 1-4)
Most manufacturers start by reviewing monitoring data remotely. They request access to your monitoring portal or ask you to share the exported data. They compare your production data against expected output for your location, array size, and panel age. If the data clearly shows underperformance below the warranty threshold, this may be sufficient to approve a claim without an on-site visit. If the data is ambiguous or shows isolated panel failures, they proceed to an on-site inspection.
Scheduling the On-Site Inspection (Weeks 4-8)
The manufacturer contracts with a local inspection firm or sends a field technician. In the Temecula and Inland Empire area, scheduling typically takes 3 to 6 weeks given the density of solar installations in Riverside and San Diego counties. You will receive a scheduling call and need to provide access to the roof and your electrical panel.
The Day of Inspection: What the Technician Does
The technician will use an IV curve tracer, which measures the current-voltage relationship of individual panels to identify underperformers. They will often use a thermal imaging camera (drone or handheld) to identify hot spots, which indicate cell-level defects or physical damage. They will check wiring connections and inverter error logs. The inspection typically takes 2 to 4 hours for a residential system. You do not need to be present on the roof, but you should be home.
Written Determination (Weeks 8-12)
After the inspection, the manufacturer issues a written determination: either approving the warranty claim, partially approving it for specific panels, or denying it with explanation. Keep a copy of this determination. If the claim is approved, they specify whether they will replace panels, reimburse you for a third-party replacement, or provide a cash settlement for the production shortfall.
Resolution and Panel Replacement (Weeks 12-24)
Panel replacement requires sourcing the correct or equivalent replacement panels and scheduling an installation crew. If the original panel model is discontinued, the manufacturer must provide equivalent or better replacement panels. The installation labor cost for replacement is often covered by the warranty. Confirm this in writing before proceeding.
7Microcracking, PID, and Delamination: The Most Common Covered Defects
Understanding the specific failure modes that warranties cover helps you use the right language when communicating with manufacturers and builds your credibility as a claimant who has done their research.
Microcracking
Microscopic fractures in the silicon solar cells that are invisible to the naked eye but detectable with electroluminescence (EL) imaging. Microcracking can occur during manufacturing, during shipping from overseas factories, or during installation when panels are walked on or improperly handled. Microcracking reduces cell efficiency and, over time, can cause cell sections to go completely dark. A panel with significant microcracking can appear physically intact while producing 15 to 30 percent below its rated output. If microcracking is identified, the cause matters: manufacturing-induced cracking is a product warranty issue; installation-induced cracking is a workmanship warranty issue.
Potential-Induced Degradation (PID)
PID is caused by high electrical potential (voltage) between the solar cells and the panel frame or mounting system, combined with moisture and high temperatures. This voltage stress causes sodium ions in the glass to migrate into the cell material, degrading the electrical properties of the silicon. PID is particularly relevant in Southern California's inland valleys, where the combination of summer heat, occasional humidity from monsoon systems, and high voltage DC systems common in large residential arrays creates favorable conditions for PID development. A system affected by PID can lose 10 to 30 percent of output within 2 to 5 years. PID is covered under product warranties if caused by a panel design flaw, and under workmanship warranties if caused by incorrect system grounding at installation.
Delamination
Solar panels are laminated assemblies with multiple layers: front glass, encapsulant (typically EVA), solar cells, another encapsulant layer, and a rear backsheet. Delamination occurs when these layers separate. It is often visible as bubbling, clouding, or discoloration behind the front glass. Delamination allows moisture to penetrate the cell area, rapidly accelerating performance loss. It is generally caused by defective encapsulant material or an inadequate lamination process at the factory, making it a clear product warranty defect. Because delamination is often visible without specialized equipment, it is one of the easier defects to document with photographs.
Hot Spots
Hot spots occur when one or more cells in a panel produce less power than the rest (due to shading, cracking, or contamination), causing the stronger cells to force current through the weaker ones, converting electrical energy to heat. Hot spots are detectable with thermal imaging and appear as localized high-temperature zones on a panel. Sustained hot spots can damage the cell and cause the bypass diode to fail. Bypass diode failure is covered under product warranties as a manufacturing defect in most cases. If a bypass diode fails and you can document it through thermal imaging or inverter error logs, that is a straightforward warranty claim.
8What Warranty Claims Do NOT Cover
Manufacturers are clear about what voids or falls outside a warranty claim. Understanding these exclusions before you file saves time and prevents frustration when a claim is legitimately denied.
Storm Damage and Hail
Physical damage from weather events is a homeowners insurance claim, not a solar panel warranty claim. Your panels are part of your home structure and should be listed on your homeowners policy. After any significant hail storm or fire near your Temecula property, call your insurance company first.
New Shading from Trees or Structures
If trees that were saplings at installation time have grown to shade your array, the resulting production loss is not a warranty issue. You may need to trim or remove those trees, or reconfigure your system. This is an operational maintenance issue, not a manufacturing defect.
Soiling and Dust Accumulation
In dry inland Southern California, dust accumulation can reduce panel output by 3 to 8 percent in summer months between rain events. Cleaning your panels is routine maintenance, not a warranty trigger. Production that returns to normal after cleaning was never a defect.
Animal or Bird Damage
Squirrels chewing wiring under panels is a common issue in wooded hillside neighborhoods around Temecula and Fallbrook. Damage from animals is excluded from manufacturer warranties. Pest prevention screens are available from installation companies and are a worthwhile investment.
Panel Modifications or Tampering
Any modifications to panels, junction boxes, or electrical connections not performed by authorized technicians voids the warranty. Do not attempt repairs yourself or hire a non-certified electrician to work on the panels.
Normal Degradation Within Guaranteed Rates
All solar panels degrade slightly each year. If your panels are degrading at 0.5 percent per year and the warranty guarantees no more than 0.7 percent per year, you are within spec even if production has declined since year one. Degradation within the guaranteed rate is not a warranty claim.
9Freedom Forever Bankruptcy and What to Do When Your Installer Goes Out of Business
Freedom Forever filed for Chapter 11 bankruptcy protection in April 2026, affecting thousands of California homeowners. If Freedom Forever installed your system, this section is particularly relevant to your situation.
Installer bankruptcy is one of the more disorienting situations for a solar homeowner because it upends the assumption that your warranty contact will still be in business for 25 years. Here is the practical reality of what happens to your warranties when an installer fails.
Panel Manufacturer Warranty: Not Affected
Your panel product and performance warranty is with the panel manufacturer, not with Freedom Forever or any installer. If Freedom Forever installed LG, Maxeon, REC, or Canadian Solar panels on your roof, those manufacturer warranties are still valid. Contact the manufacturer directly using the contact information on your warranty certificate. The installer's financial status is irrelevant to the manufacturer's obligation.
Inverter Warranty: Not Affected
Enphase, SolarEdge, Fronius, and other inverter manufacturers warrant their equipment directly. Contact them directly for inverter issues. Your Enphase warranty, for example, is between you and Enphase, and Freedom Forever's bankruptcy does not affect it.
Workmanship Warranty: Complicated
The workmanship warranty was with Freedom Forever as a contractor. Under Chapter 11, the company may continue to honor some obligations during reorganization, or those obligations may be discharged or transferred. File any workmanship warranty claims in writing immediately, before any reorganization plan is finalized. Under California law, licensed contractors are required to carry a surety bond. If Freedom Forever's bond is still active, it may provide limited recovery for warranty claims on workmanship. Contact the CSLB to determine the current status of Freedom Forever's contractor bond and license.
PPA and Lease Contracts: Separate Legal Process
If you have a power purchase agreement (PPA) or lease with Freedom Forever rather than owning the system outright, those contracts are subject to the bankruptcy court proceedings. The court may allow assignment of PPA contracts to another company. Do not stop making payments unless directed by a court order. Contact the bankruptcy trustee for guidance on your specific contract.
Immediate Steps for Freedom Forever Customers
- 1. Download and back up all production monitoring data from your portal immediately.
- 2. Locate and scan your original installation contract, warranty documents, and PPA/lease agreement.
- 3. Identify your panel manufacturer from your paperwork and locate their direct warranty contact.
- 4. Submit any pending workmanship warranty claims to Freedom Forever in writing via email and certified mail to create a paper trail predating the bankruptcy proceedings.
- 5. Monitor the bankruptcy court docket through PACER for developments that affect customer contracts.
10SunPower and Maxeon: Understanding the Warranty Split
SunPower was one of the most popular solar brands in California for over a decade. In 2023, SunPower Corporation spun off its panel manufacturing business as a separate publicly traded company called Maxeon Solar Technologies. This split created a warranty complexity that California homeowners with SunPower systems need to understand.
If Your System Was Installed Before the Split (Pre-2023)
Your warranty was originally with SunPower Corporation. Following SunPower's Chapter 11 bankruptcy filing in August 2024, warranty obligations for residential panel defects were assigned to Maxeon Solar Technologies. Maxeon has stated it will honor warranty claims for SunPower-branded panels. Contact Maxeon directly at maxeon.com/support for warranty claims on legacy SunPower systems. Keep your original warranty certificate as proof of the original terms.
If Your System Used Maxeon-Branded Panels (Post-2023)
Panels sold after the split as Maxeon brand are warranted directly by Maxeon Solar Technologies. These carry Maxeon's standard 25-year product and performance warranty, currently one of the strongest in the industry with an 88.25 percent output guarantee at year 25. Claims process through Maxeon's warranty portal directly.
For California homeowners with a SunPower installation done between 2020 and 2024, the most important step is to verify in writing that your warranty was formally assigned to Maxeon following SunPower's bankruptcy. Request written confirmation from Maxeon that your specific system's warranty is on file with them before you need to file a claim. Do not assume the assignment was automatic without getting written confirmation.
11California CSLB Requirements and Your Legal Rights as a Homeowner
California has some of the strongest consumer protections for residential construction, and solar installations fall squarely within those protections. Understanding your legal rights gives you real leverage when warranty negotiations stall.
CSLB Licensing Requirements
Every solar contractor in California who installs systems on residential properties must hold a valid CSLB license. Solar installations typically require a Class C-10 (Electrical) license and/or a Class C-46 (Solar) license. If you contracted with a company that used unlicensed subcontractors for your installation without your knowledge, you may have additional legal remedies. Verify your installer's license status at cslb.ca.gov. Enter the contractor's name or license number to see current status, any complaints filed, and bond information.
California's 4-Year Statute of Limitations on Warranty Claims
Under California law (Civil Code Section 896-945.5), residential construction defects have a statute of limitations period for legal action. For patent defects (those visible or discoverable through reasonable inspection), you have 4 years from the date you discovered or should have discovered the defect. For latent defects (those hidden and not discoverable through inspection), you have 10 years from the substantial completion of construction. Solar panel failures that develop gradually over time are often treated as latent defects, giving you up to 10 years to bring a legal claim even if the contractual warranty period has expired.
Contractor Bond Coverage
All licensed California contractors are required to carry a surety bond. As of 2024, the minimum bond amount for Class B General Contractors and Class C specialty contractors is $25,000. If a contractor fails to perform warranty work or abandons the job, you can make a claim against that bond through the CSLB. Bond claims are capped at the bond amount, but they provide a concrete avenue for recovery when a contractor goes out of business or refuses to respond to warranty claims.
California's Right to Repair Act
California's Right to Repair Act (Civil Code 895-945.5) establishes specific construction standards that residential buildings, including solar installations, must meet. These standards exist independently of any contract warranty. If your installer violated these statutory standards, you have a legal claim under California law regardless of what your contract says. The Right to Repair process requires providing notice to the contractor before filing suit, giving them an opportunity to inspect and repair. An attorney familiar with California construction law can advise on whether your situation qualifies.
12Escalation Path: CSLB, CPUC, and Small Claims Court
When a manufacturer or installer is not responding to your warranty claim, you have three formal escalation paths in California. Each serves a different purpose and applies to different situations.
CSLB Complaint (Contractor Issues)
File at cslb.ca.gov when the problem involves the licensed contractor's workmanship, failure to honor a warranty, or contractor misconduct. The CSLB investigates complaints against licensed contractors and can: issue formal citations, impose fines, place conditions on a license, suspend the license, or revoke it entirely. The CSLB also coordinates bond claims. Filing a CSLB complaint is often the fastest way to get a non-responsive installer to take action, since their license is at stake.
Best for: Installer refusing to perform warranty work, workmanship defects, contractor abandonment, or unlicensed contracting.
CPUC Complaint (Utility and Interconnection Issues)
File at cpuc.ca.gov when the problem involves your utility (SCE in Temecula and the Inland Empire) in relation to your solar system. Relevant situations include billing disputes related to NEM credits, interconnection delays, or utility metering errors that make it impossible to verify your system's actual production. The CPUC has authority over investor-owned utilities in California and can investigate utility misconduct in relation to customer solar systems.
Best for: Utility billing errors on solar accounts, NEM credit disputes, interconnection delays, or net metering plan problems.
Small Claims Court (Up to $12,500)
California small claims court handles disputes up to $12,500 for individuals. No attorney is required. You file at the Riverside County Superior Court for cases involving property in Temecula and the surrounding area. You can sue the installer, the manufacturer, or both. Before filing, send a formal demand letter via certified mail with return receipt. Give the defendant 30 days to respond. If no satisfactory response, file the claim. Bring your complete documentation package to the hearing. California judges in small claims cases often find in favor of homeowners with well-documented solar warranty claims when the defendant has failed to respond to reasonable requests.
Best for: Disputes under $12,500 where you have clear documentation and the other party is non-responsive.
13Third-Party Monitoring and Independent Inspections
When the manufacturer's own inspection process is taking too long, when you distrust the manufacturer's technician, or when the manufacturer and installer are blaming each other, an independent third-party inspection breaks the deadlock.
What a Third-Party Solar Inspector Provides
Independent solar inspectors in Southern California typically charge $300 to $800 for a residential inspection depending on system size and what tests are included. This cost is recoverable in a small claims action if you prevail. More importantly, it often resolves the claim faster than the manufacturer's own process because it provides independent, credible evidence neither party can dismiss.
Look for inspectors with NABCEP (North American Board of Certified Energy Practitioners) certification. The NABCEP PV System Inspector credential is the industry standard for qualified inspectors whose findings carry weight in both manufacturer negotiations and legal proceedings.
14Inverter Warranties vs Panel Warranties: Different Timelines and Claim Processes
Inverters are the most failure-prone component in a solar system. Unlike panels, which are passive and durable, inverters are active electronics that generate heat and experience component wear over time. Understanding the inverter warranty separately from the panel warranty prevents confusion when something fails.
| Inverter Type | Common Brands | Standard Warranty | Claim Process |
|---|---|---|---|
| Microinverter | Enphase IQ8, IQ7 | 25 years | Enphase online portal + technician dispatch |
| String inverter | Fronius, SMA, Growatt | 10-12 years (extendable) | Manufacturer support line + RMA process |
| String inverter with optimizers | SolarEdge | 12 years inverter + 25 years optimizers | SolarEdge portal + warranty claim form |
| Hybrid inverter (with battery) | Enphase, SolarEdge, Tesla | 10-15 years | Manufacturer support + battery warranty separate |
Diagnosing Inverter vs Panel Failure
Your monitoring portal is the first diagnostic tool. In a microinverter system (like Enphase), each microinverter reports independently. If one or two microinverters are failing, you will see specific panels going offline or reporting significantly lower output than their neighbors. In a string inverter system, failure of the central inverter causes the entire string or the whole system to stop producing. If monitoring shows zero production on a sunny day, check the inverter first. Inverter error codes are documented in manufacturer manuals and online. Many inverter warranty claims can be initiated by sharing the error code and monitoring data with the manufacturer online without waiting for an on-site inspection.
One important note for California homeowners: the inverter warranty timeline is often shorter than the panel warranty timeline. If your system has a 12-year string inverter warranty and 25-year panel warranty, you may face an inverter replacement cost somewhere between years 12 and 25 that is not covered under warranty. Budget for this eventuality when evaluating the long-term economics of your system.
15Buying a Home With Solar: How to Understand the Existing Warranty Status
Solar systems in Temecula and across the Inland Empire are increasingly present in real estate transactions. When you buy a home with an existing solar installation, the warranty status of that system affects its real value significantly. Here is how to evaluate it before you close.
Request the Original Installation Documents
Ask the seller for: the original installation contract and proposal, the warranty certificates for panels and inverter, the city or county permit for the installation, the NEM agreement with SCE, and the most recent 12 months of monitoring data. A seller who cannot produce these documents cannot make any warranty representations about the system. Treat missing documentation as a due diligence red flag.
Verify Warranty Transferability
Most manufacturer panel warranties are fully transferable to subsequent homeowners. Verify this in the warranty certificate language for the specific panels on the home you are purchasing. Some workmanship warranties from installers are not transferable or have reduced terms after transfer. Read the actual warranty document, not the sales brochure summary. If the installer is no longer in business, note that only the manufacturer warranty remains.
Check the System Against Its Production History
Compare the current system's production data to the original proposal estimate. If a 10-year-old system is producing 30 percent below what was originally estimated, that is either normal degradation that is within warranty (check the guaranteed rate) or underperformance that was never addressed. Either way, it affects the value of the system and your potential utility savings. Request the monitoring data export and run the numbers yourself.
PPA and Lease Systems: Different Rules
If the home has a solar PPA or lease (where the solar company owns the panels and the homeowner buys the power), the situation is fundamentally different. You are not buying the solar system when you buy the home. You are assuming the PPA or lease contract, including all remaining payment obligations, escalator clauses, and any early termination fees. Have a real estate attorney review the PPA agreement before you close on any home with a third-party-owned solar system. PPA assignments require lender approval, which can complicate financing.
Schedule a Pre-Purchase Solar Inspection
Just as you hire a general home inspector before purchasing a property, hire a NABCEP-certified solar inspector to assess the system. A pre-purchase solar inspection costs $300 to $500 and covers panel condition, inverter health, wiring integrity, and production history analysis. Issues found during inspection become negotiating points. A system with documented problems but intact manufacturer warranties may still be a good purchase if the seller reduces the price to account for warranty service costs.
Frequently Asked Questions
How do I know if my solar panels are underperforming and not just experiencing a bad weather stretch?
Compare your system's actual monthly production against the production estimate in your original proposal. Most installers provide a year-one estimate broken down by month. If you are consistently producing 10 percent or more below the estimate after adjusting for unusually overcast months, that is a red flag worth investigating. Your monitoring app (Enphase Enlighten, SolarEdge, or similar) shows daily and monthly totals. Download 12 consecutive months of data and compare it to your proposal numbers. A single bad month means little. Sustained underperformance across multiple months, especially in summer peak months in Southern California, warrants a warranty inquiry.
What is the difference between a product warranty and a performance warranty on solar panels?
A product warranty (also called a materials or equipment warranty) covers physical defects in the panel itself: manufacturing flaws, delamination, corrosion, broken cells, and frame failures. These typically last 12 to 25 years depending on the manufacturer. A performance warranty (also called a power output or linear warranty) guarantees that the panels will produce at least a minimum percentage of their original rated output over time. Most premium panels in 2026 guarantee 80 to 87 percent of original output at year 25, with a maximum annual degradation rate of 0.4 to 0.7 percent per year. If your panels fall below the guaranteed output threshold, that triggers a performance warranty claim even if the panels look physically intact.
Who is responsible for my solar warranty: the manufacturer or the installer?
It depends on the type of defect. Panel manufacturer defects (cracked cells, delamination, electrical failures inside the panel) are handled by the panel manufacturer directly. Inverter failures are covered by the inverter manufacturer separately. Workmanship defects, improper mounting, incorrect wiring, and roof penetration problems are the installer's responsibility under their workmanship warranty, which typically lasts 1 to 10 years. If your installer is no longer in business, you deal with the manufacturer directly for panel defects, but workmanship claims may require a CSLB complaint or small claims court. In California, a licensed solar contractor is legally required to honor their workmanship warranty even after ceasing new installations.
What documentation do I need to file a solar warranty claim?
Gather these items before contacting anyone: (1) Your original proposal showing the estimated annual and monthly production numbers. (2) The warranty certificate or section of your installation contract that states the specific warranty terms. (3) Twelve or more months of monitoring data showing actual production figures, exported from your monitoring portal as a PDF or CSV. (4) Your utility bills showing actual grid consumption to cross-check the monitoring data. (5) Photos of any visible physical damage or discoloration on the panels. (6) A record of any shade changes on your property such as trees that have grown since installation. Having all of this organized before you make the first call significantly speeds up the claim process.
What happens to my solar warranty if my installer went out of business?
If your installer went out of business, your panel performance and product warranty with the panel manufacturer remains valid. The manufacturer is still contractually obligated to honor it regardless of the installer's status. Contact the manufacturer directly using the contact information on your warranty certificate. For workmanship warranty issues, the situation is more complex. In California, if a licensed contractor abandons their business without honoring warranty obligations, you can file a complaint with the Contractors State License Board (CSLB). California's contractor bond system provides limited recovery for consumers harmed by contractor failures. You may also have recourse through your homeowners insurance or the financing company that funded your installation.
How long does a solar warranty inspection take from start to finish?
After you submit a formal warranty claim with documentation, most manufacturers acknowledge receipt within 5 to 10 business days. They will then schedule either a remote data review or an on-site inspection. Remote reviews typically take 2 to 4 weeks. On-site inspections, where a technician visits your property to test individual panels with IV curve tracers and thermal imaging, typically take 4 to 8 weeks to schedule depending on the manufacturer's service network density in your area. After the inspection, you receive a written determination within 10 to 30 days. If panels are found defective, replacement or compensation typically follows within 30 to 90 days. Total timeline from claim submission to resolution: 2 to 6 months in most cases.
What is potential-induced degradation and is it covered under warranty?
Potential-induced degradation (PID) is a failure mode where stray electrical currents within the solar panel degrade the photovoltaic cells over time. It is caused by high voltage stress between the solar cells and the panel frame or mounting structure, often accelerated by humidity and heat. California's climate, particularly in hot inland areas like Temecula and the Inland Empire, creates conditions where PID can develop faster than in cooler coastal markets. PID is generally covered under both product and performance warranties if it causes output to fall below the guaranteed threshold. The important distinction is that PID from improper grounding during installation is a workmanship defect covered by the installer, while PID from a panel design flaw is covered by the manufacturer.
How do I escalate a solar warranty dispute if the manufacturer or installer is not responding?
In California you have three escalation paths. First, file a complaint with the Contractors State License Board (CSLB) at cslb.ca.gov if the issue involves a licensed contractor's workmanship or failure to honor a warranty. The CSLB investigates complaints and can discipline, suspend, or revoke a contractor's license. Second, for disputes involving the utility interconnection or billing related to your solar system's underperformance, file a complaint with the California Public Utilities Commission (CPUC) at cpuc.ca.gov. Third, for disputes under ten thousand dollars, small claims court is an efficient option. In small claims court, you do not need an attorney, and California allows you to sue out-of-state manufacturers if the warranty was for property installed in California. Always send your final demand letter via certified mail before filing any complaint or lawsuit.
Not Sure If Your System Is Underperforming?
We review solar production data for Temecula and Murrieta homeowners at no charge. Bring your monitoring export and original proposal and we will tell you in plain language whether your numbers look right and what your options are.
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