What an Inverter Failure Costs, and What a Repair Restores: 14 Verified Repairs on LA Systems
Across 14 documented inverter replacements on Los Angeles-area solar systems, production returned to a median 99% of its pre-failure level (95–106% in all but one case). A failure cost a median 7% of a year’s normal output, usually one or two months of lost or reduced production. From the first report to a new inverter showing in monitoring took a median 16 days (9–31 for the middle half); much of that is the manufacturer shipping the replacement unit.
What happens to production around an inverter replacement
Performance against the fleet, month by month, median of all cases. 1.0 = a typical system that month.
Before the failure the systems ran at about 1.06 of a typical system. Output collapsed in the month before and the month of the replacement — that is where the loss sits — and from the next month the systems were back to about 1.02. A replacement inverter does not make a system better or worse than it was; it puts it back.
Case by case
Every verified replacement with comparable data before and after.
| Case | Replaced | Months affected | Year’s output lost | Before | After | Restored | Days to new inverter |
|---|---|---|---|---|---|---|---|
| Case 1 | 2020-07 | 1 | 5% | 1.09 | 1.04 | 95% | — |
| Case 2 | 2020-08 | 1 | 4% | 1.02 | 1.08 | 105% | — |
| Case 3 | 2021-06 | 2 | 12% | 1.08 | 1.06 | 98% | 17 |
| Case 4 | 2022-02 | 2 | 10% | 1.06 | 1.06 | 99% | 32 |
| Case 5 | 2022-10 | 2 | 9% | 1.10 | 1.10 | 100% | 27 |
| Case 6 | 2023-04 | 2 | 10% | 1.20 | 1.16 | 97% | 16 |
| Case 7 | 2023-08 | 1 | 6% | 0.99 | 1.00 | 101% | 15 |
| Case 8 | 2023-09 | 1 | 3% | 1.02 | 1.09 | 106% | 9 |
| Case 9 | 2023-09 | 1 | 5% | 0.93 | 0.92 | 99% | 10 |
| Case 10 | 2023-09 | 1 | 4% | 1.03 | 1.05 | 101% | 13 |
| Case 11 | 2024-01 | 2 | 8% | 0.96 | 0.94 | 97% | 8 |
| Case 12 | 2025-02 | 4 | 13% | 0.96 | 0.92 | 97% | 34 |
| Case 13 | 2025-02 | 1 | 3% | 1.07 | 1.06 | 98% | 6 |
| Case 14 | 2025-08 | 2 | 14% | 0.82 | 1.00 | 122% | 35 |
| Before / After: performance index (1.0 = typical system that month). Restored = After ÷ Before. Days: from the first report in our service records to the new inverter appearing in monitoring; — where the start is not in the records. | |||||||
https://cali-energy.com/research/solar-inverter-repair-production. Aggregated data are free to use under CC BY 4.0 with a link to this page.Every case came back to between 95% and 106% of its prior level, except one that came back higher (122%): its output had already been slipping for months before the inverter stopped, so its “before” level was already low. The cost of a failure depends mostly on how long it goes unnoticed: one month affected typically cost about 4% of a year’s output, two months about 10%. For a 6 kW system making about 8,740 kWh a year, 7% is roughly 630 kWh.
How the failures showed up
Sudden stop: 12 of 14
Output fell from normal to near zero within a month. In the app this is a flat line during daylight — easy to spot if someone looks.
Slow slide: 2 of 14
Output drifted down for three or four months before the inverter stopped. Comparing each month with the same month last year catches this earlier.
Not every zero is a failure
A broken internet connection also shows zero in the app while the panels keep producing. See a case where the system was fine.
Check it yourself
Compare a month with the monthly benchmark or a year with the fleet’s change.
What a warranty inverter replacement involves
The sequence in our service records.
- 1. Detection
- The homeowner, the monitoring alert or our team notices the system is not producing.
- 2. Diagnosis
- The inverter’s error codes and production history go to the manufacturer. Sometimes a site visit comes first to rule out wiring, breakers or communication.
- 3. Warranty case
- The manufacturer opens a case and approves a replacement (an RMA). 15 of the 17 replacements in our records went through a SolarEdge case.
- 4. Shipping
- The replacement unit ships to the installer. In our records this wait is the longest step.
- 5. Replacement and commissioning
- A crew swaps the inverter, confirms it is producing and reconnects it to monitoring. A communication module sometimes needs its own follow-up.
From first report to the new inverter in monitoring, the 14 cases with a dated start ranged from 6 to 49 days, median 16. The shortest went from a manufacturer case to a working inverter within a week; the longest waited weeks for the replacement unit or for a service visit to be scheduled. For costs and options when the inverter is out of warranty, see inverter replacement cost.
Methodology
- Cases
- Inverter replacements recorded in the monitoring account (a new inverter registered in place of the old one) and confirmed one by one in our service correspondence: 17 replacements on 14 systems, 2020–2026. Replacements that appear in device records but are not documented in our correspondence are not included, nor are swaps made during commissioning.
- Before and after
- 14 cases have at least six months of usable data on both sides. Three confirmed cases are not compared: one system was expanded around the same time, one lost its monitoring connection for months after the swap, and one was replaced too recently.
- Performance index
- Monthly kWh per kW divided by the median of all monitored systems in the same month. It removes weather and season, so months from different years compare.
- Before / After level
- Median index over months −12 to −2 and +2 to +12 from the replacement month, leaving out months below 0.75 (failure or outage months).
- Output lost
- In months −6 to +1 with an index below 0.75: the shortfall against the system’s own “before” level, as a share of its normal year.
- Days
- From the first message about the problem or the warranty case in our records to the date the new inverter appears in the monitoring account. Registration in monitoring can lag the physical swap by a few days.
- Limits
- All cases are SolarEdge inverters with monthly data; a failure inside a month is seen as a partial month. Customer names and addresses are not published.
Frequently asked questions
Does solar production go back to normal after an inverter replacement?
In our verified cases, yes: output returned to a median 99% of the system’s own pre-failure level, 95–106% in all but one case.
How much production do you lose when a solar inverter fails?
A median 7% of a normal year in our cases (4–10% for the middle half), mostly from one or two months of near-zero output. The longer a failure goes unnoticed, the more it costs.
How long does a solar inverter replacement take?
From the first report to the new inverter showing in monitoring took a median 16 days in our records (6–49 days). Waiting for the manufacturer’s replacement unit was usually the longest step.
How do I know if my solar inverter has failed?
A flat line at zero in the monitoring app on sunny days, or no lights or an error code on the inverter. Check the home’s internet connection too: a lost connection can also show zero while the panels keep producing.
Is a failed inverter replaced under warranty?
In our records, 15 of 17 replacements went through a manufacturer warranty case (RMA). Coverage and labor terms depend on the product and the installer’s warranty.
More research
Next steps
Your system has stopped or slowed down?
Prepared by Cali Energy, October 7, 2026. Figures describe systems in our monitoring fleet and are not a guarantee of what any specific roof will produce; orientation, tilt, shade, equipment and weather change results. Not engineering, financial or utility advice. See our Content Disclaimer.