solar troubleshooting
Inverter shows fault or no output
Common symptoms: inverter fault code; inverter no output; inverter offline; red light on inverter; no solar production at all
Stop and call a pro if:
- PV conductors are energized in daylight even when the inverter is off — never open DC connectors or the DC isolator under load (arc-flash)
- AC and DC sides can both be live; treat all conductors as energized
- leave fault clearing on hardware inside the inverter to a licensed installer
Step-by-step diagnostic flow
Step 1
Do you see or smell smoke, burning, scorched/melted housing, or hear arcing/buzzing from the inverter or disconnects?
These indicate an active electrical hazard on a live system.
Step 2
What is the inverter showing right now?
Most inverters use a green light for normal, and a red/orange light or a fault code on the display or app for a problem.
Step 3
Is the AC disconnect switch ON and is the solar breaker in your main panel set (not tripped)?
Only operate clearly labeled AC switches/breakers — flipping a breaker is fine; opening enclosures is not. Do NOT operate the DC isolator under load.
Step 4
Is the grid power to the house normal, or is there an outage / recent voltage problem?
Grid-tied inverters stop producing during an outage or out-of-range grid voltage (anti-islanding) to protect line workers — this is required behavior, not a defect.
Step 5
Look up the exact fault code in the inverter manual or app. Does it describe a clearable condition (e.g. grid waiting/reconnect) or a hardware fault (ground fault, arc fault, isolation, over-temperature, internal)?
Ground-fault, arc-fault, and isolation faults indicate a wiring/insulation problem on the DC side and are NOT homeowner-clearable.
Possible outcomes
Stop — possible electrical fire hazard
high confidenceSmoke, burning, melted housing, or arcing from inverter/disconnects is an active hazard on an energized system.
- Trigger rapid shutdown if you can reach it safely
- Keep clear of the equipment
- Call your installer; call the fire department if there is smoke or heat
AC disconnect/breaker was open — output restored
high confidenceA tripped solar breaker or an open AC disconnect stops the inverter from exporting; resetting it restored production.
- Confirm production resumes within a few minutes
- If the breaker trips again, stop resetting it and call your installer — repeated tripping signals a fault
- Whether the breaker has tripped more than once
- Inverter make and model
No output is expected during a grid outage (anti-islanding)
high confidenceGrid-tied inverters without battery backup are required to shut down during an outage or out-of-range grid voltage to protect utility workers.
- Wait for grid power to return — the inverter reconnects automatically after a stabilization delay
- If output doesn't return well after the grid is stable, re-run this workflow
- Whether you have battery backup
- Times the grid went down and came back
Self-clearing grid/reconnect condition
medium confidenceGrid-waiting and reconnect codes clear on their own once grid conditions are back in range.
- Give the inverter its full reconnect delay (often several minutes)
- Verify grid voltage looks normal at the house
- If it persists for hours with a healthy grid, contact your installer
- The exact code shown
- How long it has persisted
Hardware fault — call your installer, do not clear it yourself
high confidenceGround-fault, arc-fault, isolation, over-temperature, and internal faults indicate a DC wiring/insulation or equipment problem that requires opening live equipment and is not homeowner-serviceable.
- Do not open the DC isolator under load or open any enclosure
- Photograph the fault code and indicator
- Schedule your installer; reference the warranty
- Exact fault code and inverter model
- When the fault started and whether it repeats
- Any recent roof/electrical work or weather event
Code unknown — have your installer interpret it
low confidenceAn uninterpreted fault code can't be safely acted on; some codes indicate dangerous DC-side conditions.
- Photograph the code and the model/serial label
- Contact your installer or the manufacturer's support line
- Exact code text/number
- Inverter make, model, and serial number
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