Solar Panels Not Working? A Step-by-Step Troubleshooting Guide

Waking up to find your solar monitoring app showing zero production is a stressful experience. But before you panic and assume you need entirely new equipment, know that most solar issues are caused by minor, easily fixable faults.

In this troubleshooting guide, we will walk you through the most common reasons your solar panels might not be working and how to safely diagnose them.

Step 1: Check the Basics

Before diving into complex electrical diagnostics, rule out the obvious external factors:

• Is it nighttime? Solar panels don’t produce power in the dark.
• Is the grid down? If your neighborhood has a power outage and you don’t have a battery backup, your solar system will automatically shut off for safety reasons.
• Is there heavy shading? Check for new tree growth, a heavy accumulation of snow, or debris (like a thick layer of leaves) covering the panels.
• Has your internet disconnected? Often, the system is producing power perfectly fine, but your home Wi-Fi changed passwords or the router restarted, causing the monitoring app to go offline.

Step 2: Inspect the Inverter Lights and Codes

Your inverter is the brain of the system and will usually tell you exactly what is wrong.

String Inverters (SolarEdge, SMA, Fronius)

Locate the main inverter box, usually mounted on the side of your house near the electrical meter or in the garage.

• Solid Green Light: Normal operation, producing power.
• Flashing Green Light: Waiting for sufficient sunlight, or grid connecting.
• Solid or Flashing Red Light: System fault. Look at the digital display screen (if applicable) for a specific error code. Document this code—your technician will need it.

Microinverters (Enphase)

Check the Enphase Envoy (Gateway) box.

• You should see solid green LEDs.
• If the lights are red, open your Enphase Enlighten app. It will flag which specific microinverter (and panel) on the roof is failing.

Step 3: Check for Tripped Breakers

A sudden power surge or a minor electrical anomaly can cause the system’s safety breakers to trip.

1. Main Electrical Panel: Go to your home’s main breaker box. Look for a breaker labeled “Solar,” “PV,” or “Photovoltaic.” If it is in the middle (tripped) or OFF position, firmly push it all the way to OFF, then snap it back to ON.
2. AC Disconnect Switch: Near your inverter or utility meter, there is usually a grey box with a large lever. Ensure this lever is in the “ON” (usually up) position.
3. Inverter Breakers: Some string inverters have small internal breakers or a dial switch on the bottom. Ensure they are turned to the ON or ‘1’ position.

Step 4: Perform a Hard Reset

If the breakers are fine but the inverter is frozen or showing an error, a hard reset often clears temporary faults. Follow this specific sequence:

1. Turn OFF the Solar breaker in your main electrical panel.
2. Turn OFF the AC Disconnect lever.
3. Turn OFF the DC Disconnect switch (usually a dial on the bottom of the inverter).
4. Wait 5 full minutes to allow the capacitors to discharge.
5. Turn everything back ON in the reverse order (DC Disconnect, then AC Disconnect, then Main Breaker).
6. Wait 10-15 minutes. The inverter needs time to run safety checks before reconnecting to the grid.

When to Call a Professional

If you have performed a hard reset, verified the breakers are on, and the system is still showing a red light or zero production, it is time to call a certified solar repair company.

Do NOT attempt to:

• Climb the roof to inspect the wiring. DC voltage from solar panels can be lethal.
• Open the inverter casing.
• Attempt to bypass any fuses or disconnects.

By documenting the error codes and the steps you’ve already taken, you’ll save your repair technician time and get your system back to producing clean energy much faster.