Guide · Diagnostics
Why Your Solar Stopped Producing
Direct answer
Most Gold Coast solar systems that stop producing fail in one of four places: the inverter, the DC strings, the monitoring connection, or the AC supply. A diagnostic Solar Health Check identifies which one within an hour or two.
Most Gold Coast solar systems that stop producing are failing in one of four places: the inverter, the DC strings, the monitoring connection, or the AC supply. A diagnostic site visit identifies which one within an hour or two, with a written report and repair quote regardless of whether you proceed.
The four common failure modes
When an owner says “my solar stopped working,” the cause is almost always one of these. None of them are obvious from inside the house. You need eyes on the inverter screen, the strings, and the meter together.
1. Inverter fault
The inverter is the brain of the system. It converts the DC the panels produce into the AC that runs your house. When it fails, production stops cold.
Common failure patterns on the Gold Coast:
- Capacitor failure, typical after 7–10 years of heat exposure
- Insulation resistance fault, often after storm season water ingress
- DC overvoltage on cold sunny mornings, panel string oversized for the inverter
- Communication board failure. The inverter still produces but you can’t see anything
Manufacturer fault codes tell most of the story. Fronius shows them on the screen and in Solar.web. SMA shows them on the display and in Sunny Portal. Sungrow and GoodWe both have app interfaces. The codes are documented in the manufacturer’s installation manual, most of which are publicly available.
2. String fault
The “strings” are the series chains of panels feeding DC into the inverter. A single panel fault, a damaged MC4 connector, water ingress in a junction box, or a rodent-chewed cable can take an entire string offline.
Diagnosis requires open-circuit voltage testing on each string (measured against expected Voc × number of panels × temperature correction), insulation resistance testing per AS/NZS 5033, visual inspection of all MC4 connections, and thermal imaging if individual cell hot-spots are suspected.
3. Monitoring connection lost
Sometimes the system is producing. You just can’t see it. The Wi-Fi connection to the inverter has dropped, the cloud monitoring portal has changed authentication, or the original installer’s monitoring account has been closed.
This is the cheapest fix and the most commonly mistaken for a “broken” system. Worth checking before assuming the worst.
4. AC supply or grid issue
Less common, but real. Failed isolators, tripped circuit breakers, blown fuses on the AC side, or grid-side voltage outside the inverter’s tolerance band. Summer afternoons in Queensland routinely push grid voltage above 253V, at which point inverters disconnect to protect the grid. The system isn’t broken. The grid is.
What a Solar Health Check involves
A Solar Health Check is around two hours on site plus the report writing. The work covered:
- Inverter inspection and fault log review
- DC string testing: open-circuit voltage and short-circuit current per string
- Insulation resistance testing per AS/NZS 5033
- AC supply check: voltage, frequency, isolator function
- Visual inspection: panels, mounting, cable runs, junction boxes, switchboard tie-in
- Monitoring account audit, whether your data is still being captured
- Photo documentation of every component checked
You receive a written PDF report identifying the fault, ranking severity, and recommending next steps. If repair is needed, a separate fixed-price quote follows the report. If your panels are still under warranty, the report gives you what you need to make a manufacturer claim, whether or not Iron and Air does the repair.
What it costs
The Solar Health Check starts from $250 in Zone 1, with travel-bundled pricing for Zones 2 and 3. See the pricing page for the zone breakdown. Repair work is quoted separately based on what’s found. Common repair costs for context:
| Repair | Typical range |
|---|---|
| Wi-Fi monitoring re-link | $0–$120 (often resolved during the diagnostic visit) |
| Single MC4 connector replacement | $150–$250 |
| String replacement | $400–$800 |
| Inverter replacement | $2,500–$6,500 depending on size and brand |
| Panel replacement | Variable, coordinated through manufacturer warranty |
When to call, and when not to
Call when the system has been off for more than two weeks, production has dropped more than 20% versus the same month last year, the inverter screen shows a fault code you can’t clear, or you’ve lost contact with the original installer.
Don’t call for a single overcast week (production drops are normal), a 5% year-on-year reduction (panel degradation is normal at around 0.5% per year), or an issue already covered under an active warranty. Call the manufacturer first.
Common questions
Will the original installer still be on the hook? If they’re still in business, yes. Australian Consumer Law requires that work be carried out with due care and skill, with a reasonable durability expectation that’s typically 7–10 years for solar workmanship. If the original installer is gone, the manufacturer warranty on panels (usually 25 years) and inverter (5–10 years) is still valid but you’ll need to coordinate the claim yourself. The Health Check report is what you need to do that.
Can I just replace the inverter myself? No. Inverter replacement is grid-connection work that requires SAA accreditation (the scheme that replaced CEC accreditation in 2024) and DNSP notification. Doing it yourself voids insurance, manufacturer warranty, and STC eligibility on the new equipment.
My system was installed 12 years ago. Is it worth repairing? Sometimes. If panels are still producing close to their rated output, replacing just the inverter is often economical. If multiple strings are degraded and the inverter is failing, full replacement with new panels is usually better value than chasing repairs across an ageing system. The Health Check tells you which case you’re in.
What if I just want a second opinion on a quote I’ve received? That’s a valid use of the Health Check. The report gives you an independent assessment you can put alongside any other quote. If the other installer is right, you’ve spent the audit fee to confirm it. If they’re wrong, you’ve saved a lot more.