Troubleshooting Common Solar System Problems: A Homeowner Guide

When your solar system isn't performing as expected, it's natural to worry. Most issues have straightforward causes, and many can be diagnosed before calling a technician. Here's your guide to understanding and addressing common solar problems.

Quick Diagnostic Checklist

Before diving into specifics, check these basics:

Zero Output Issues

System Producing Nothing

Most common causes:

1. Inverter shutdown

   • Check for error lights/messages
   • Look for display completely off

2. Isolator switched off

   • AC isolator at switchboard
   • DC isolator near panels
   • Isolator at inverter

3. Grid outage

   • Check if neighbours have power
   • Solar shuts down during outages (safety requirement)

4. Tripped circuit breaker

   • Check switchboard for tripped solar breaker
   • May indicate fault—call electrician if it trips again

Troubleshooting Steps

1. Check inverter is powered on and displaying
2. Verify all isolators are in ON position
3. Confirm grid power is available
4. Check switchboard for tripped breakers
5. Review monitoring app for error history
6. If all clear, contact installer

Low Output Problems

System Underperforming

Calculate expected vs actual:

Common Causes

Environmental:

• Dirty panels (dust, pollen, bird droppings)
• New shading (tree growth, new structure)
• Weather (clouds, smoke, haze)

System issues:

• Panel damage or degradation
• Inverter efficiency loss
• Wiring problems
• Faulty monitoring (actual output may be fine)

Diagnosis Steps

1. Compare to historical data — Same time last year?
2. Check neighbouring systems — Similar reduction?
3. Visual panel inspection — Obvious dirt or damage?
4. Weather comparison — Similar conditions?
5. Clean panels — Often the simple fix

Inverter Error Codes

Fronius Error Codes

Sungrow Error Codes

Enphase (Microinverter) Alerts

What Errors Mean

Temporary errors (usually self-resolve):

• Grid voltage fluctuations
• Communication interruptions
• Brief overtemperature

Errors requiring attention:

• Persistent (same error repeatedly)
• Arc fault warnings
• Insulation faults
• Physical damage alerts

Grid Overvoltage Issues

Understanding Overvoltage

Australian standard voltage is 230V (range: 216-253V). Problems occur when:

Why It Happens

• High solar penetration in your area
• Light grid load during sunny periods
• Long distance from transformer
• Grid infrastructure issues

Solutions

1. Volt-Watt mode — Inverter limits export at high voltage
2. Volt-VAR mode — Helps stabilise voltage
3. Export limiting — Reduces power sent to grid
4. Battery storage — Use excess instead of exporting
5. Network complaint — DNSP may need to upgrade infrastructure

Documenting for Network

If persistent, record:

• Time and date of shutdowns
• Voltage readings (if visible on inverter)
• Duration of issues
• Screenshot error messages

Submit to your network (Powercor/Jemena/AusNet) via their online form.

Physical Panel Issues

Signs of Damage

What to Do

Do NOT touch damaged panels — they may be energised

1. Photograph the damage
2. Note which panel(s) affected
3. Check monitoring for affected production
4. Contact installer with photos
5. If burn marks or fire risk, turn off DC isolator

DC Isolator Problems

Common DC Isolator Issues

DC isolators (required in Australia) are a known weak point:

Signs of problems:

• Buzzing or crackling sounds
• Burning smell
• Discolouration or melting
• Tripping repeatedly

Why they fail:

• Water ingress (outdoor location)
• Arc damage over time
• Poor quality components
• Inadequate installation

Action Required

If you notice any of these signs:

1. Do not touch the isolator
2. Turn off AC isolator at switchboard
3. Call installer or electrician immediately
4. This is a potential fire risk—don't delay

Monitoring System Issues

App Not Updating

Reconnecting WiFi

Most inverters:

1. Access inverter menu via display
2. Navigate to Settings > WiFi
3. Select your network
4. Enter password
5. Confirm connection

Specific instructions vary by brand—check manual.

Data Discrepancy

If monitoring shows different values than meter:

• Monitoring is instantaneous; meter is cumulative
• Check time periods match
• Export meter may show different figure than total generation
• Some loss between generation and export is normal (self-consumption)

When to Call a Professional

Call Immediately If:

• Burning smell from any component
• Visible burn marks or melting
• Sparking or arcing
• Arc fault warning code
• Persistent insulation fault error
• Water inside any electrical component

Schedule Service For:

• Persistent error codes
• Significant output reduction (>20%)
• Physical panel damage
• DC isolator concerns
• Repeated tripped breakers
• System over 2 years since last inspection

What to Have Ready

When calling your installer:

1. System install date and size
2. Inverter make/model
3. Error codes displayed
4. Timeline of issues
5. What you've already checked
6. Photos if relevant

Preventive Measures

Regular Checks (Monthly)

• Glance at inverter display
• Check monitoring app
• Look for visual changes on roof

Quarterly Actions

• Clean panels if needed (or arrange cleaning)
• Clear vegetation that may cause shading
• Check for bird nesting

Annual Inspection

Professional service should include:

• Thermal imaging of panels
• Connection testing
• Inverter diagnostics
• Mounting hardware check
• Performance verification

The Bottom Line

Most solar issues fall into predictable categories:

1. Zero output — Usually isolators or grid issues
2. Low output — Often dirty panels or weather
3. Inverter errors — Many resolve automatically
4. Overvoltage — Common in high-solar areas
5. Physical damage — Requires professional assessment

Document issues, check the basics, and don't hesitate to call your installer for anything electrical or concerning.

Contact H.T Electrics and Solar for system diagnosis, maintenance, or any solar concerns.