10 Common Solar Inverter Problems & How to Fix Them

Your solar inverter is the brain and heart of your PV system, converting DC electricity from solar panels into usable AC power. However, like any electrical device, they can face technical issues that impact performance. If your solar inverter is not working, don’t worry. Many problems can be easily diagnosed and fixed. This guide helps you immediately troubleshoot the most common solar inverter problems.  

We’ll dive deep into the top 10 solar inverter failure codes and issues, providing clear DIY troubleshooting steps and critical advice on when to contact a certified technician. Plus, we’ll introduce Elios Solar Inverters, a trusted and highly efficient solution for long-term solar efficiency.

1# Inverter is Dead: Not Powering On (No Display/Lights)

Safety First: Before checking any connections, ensure you have flipped both the AC and DC disconnect switches (if applicable) to the OFF position. Use a non-contact voltage tester to verify the system is de-energized.

Possible Causes:

• No power supply or system shutdown
• Loose connections in the wiring
• Battery or grid failure (for hybrid or grid-tied systems)

How to Fix:

• Check Fuses and Breakers: Verify the main circuit breaker for the solar system on your home’s AC panel hasn't tripped. Also, check for any visible fuses near the inverter or in the main combiner box.
• Ensure the battery is charged (for off-grid or hybrid systems).
• Inspect DC Wiring (MC4 Connectors). Look for any visible scorch marks or loose MC4 connectors coming from the solar panels into the inverter. Only check connections if you are comfortable and have de-energized the system.
• If grid-connected, verify that your home’s power supply is working.

If the inverter still won’t start, reset it by turning it off for 5 minutes and restarting. Turn OFF the AC disconnect, then turn OFF the DC disconnect (or vice-versa, depending on your manual). Wait a full 5 minutes for residual voltage to discharge. Turn the DC back ON, wait 60 seconds, then turn the AC back ON.

2# Blank or Unresponsive Display

Possible Causes:

• The inverter is running, but the screen is dark.
• The entire unit is off (see Issue #1).
• Specific Causes for Blank Screen: Overheating (causing a temporary shutdown), firmware glitch, or a loose ribbon cable/damaged LCD screen.

How to Fix:

• Ensure the inverter is receiving power from the solar panels or grid. Listen closely. Is the cooling fan running, or do you hear a slight hum? If yes, the inverter may be working, but the display is faulty. If no, proceed to the Hard Reset from Issue #1.
• Check for tripped circuit breakers or blown fuses.
• If the issue persists, the display may need to be replaced by a technician.

3# Inverter Displaying a Specific Fault Code or Error

Common Categories of Error Codes: Voltage Errors (Grid/PV), Isolation Faults (Ground Faults), Frequency Mismatch, Temperature Shutdown.

Possible Causes:

• System overload
• High or low voltage fluctuations
• Internal software issues

How to Fix:

• Refer to the solar inverter manual to decode the error message. Search for the exact code (e.g., Error F101 or State 307) online with your inverter's brand and model number for the fastest description.
• Check Grid Voltage: If the code suggests 'Over-Voltage' or 'Under-Voltage,' you may be experiencing a grid surge. If this is a recurring issue, you will need a technician to adjust the inverter's voltage limits.
  
• Restart the inverter and see if the error clears.

Some premium inverters, like Elios Solar Inverters, come with smart diagnostic tools to simplify troubleshooting.

4# No Power Output from the Inverter

Possible Causes:

• Low solar energy input
• A recently installed or repaired smart meter (Net Metering) is incorrectly configured or has a delay in connection after a grid outage.
• Faulty wiring or disconnected solar panels
• Internal inverter malfunction

How to Fix:

• Check if solar panels are producing energy using a multimeter. Visually check for debris (like snow, leaves, or bird droppings) on your panels.
  • Safety Warning: Only use a multimeter to check voltage after disconnecting the entire system, and if you have electrical training. Do not attempt this while the system is connected.
• Inspect the wiring and connections between the inverter and panels. Check for signs of damage or loose connectors near the inverter, which are a common point of failure due to weathering.
• Reset the inverter and see if it starts producing power.

If the issue persists, the problem is internal. Contact Volts. We can arrange for a certified technician to test the unit or explore replacement options like a high-efficiency hybrid inverter from our selection.

5# Inverter is Overheating (Thermal Shutdown) 

Possible Causes:

• Poor ventilation around the inverter: Blocked Exhaust Vents (spiderwebs, insect nests), or Mounting Too Close to Other Equipment (e.g., a battery enclosure).
• Dust accumulation inside the unit
• High ambient temperatures
  

How to Fix:

• Ensure proper airflow around the inverter by keeping it in a well-ventilated area.
• Use a soft-bristle brush or compressed air to gently clean dust from the fan and heat sink fins. NEVER spray liquid directly onto the unit.
  
• Move the inverter to a shaded area if it's exposed to direct sunlight. If moving is not possible, consider installing a simple sun shield or protective canopy above the unit to reduce direct solar gain without restricting airflow.

For long-term reliability in harsh climates, consider an inverter with superior thermal management. Elios Solar Inverters are engineered with advanced cooling systems to prevent overheating and improve efficiency.

6# Solar Inverter is Making Buzzing or Grinding Noises

Possible Causes:

• Grinding/Scraping: Likely a failing internal fan.
• Loud Buzzing/Humming: Often a loose internal transformer or a severe electrical fault (arcing).

How to Fix:

• If the noise stops when the fan stops, it's a fan issue.
• Check if any screws or internal components are loose.
• If the noise is a constant, loud electrical buzzing, immediately switch OFF the AC and DC disconnects and call a technician.
  

When to Call: Any loud, electrical buzzing or smoking indicates immediate danger. DO NOT ATTEMPT TO OPEN THE UNIT. Contact our professional technician for diagnosis.

7# Solar Inverter Not Connecting to WiFi or Monitoring App

Possible Causes:

• Poor WiFi signal strength
• Incorrect network configuration
• Router Channel/Frequency Issue (Inverters often use the older 2.4GHz band only)
• Firmware issues

How to Fix:

• Ensure your WiFi router is within range of the inverter. Use a WiFi extender or reposition your router if the signal strength is weak at the inverter's location. 
• Reset your inverter’s WiFi settings and reconnect.
• Update the inverter firmware through the manufacturer’s app. Ensure your inverter is running the latest firmware version. Check the manufacturer's website or the monitoring app for available updates. Warning: Only update firmware when the unit has sufficient power to avoid bricking the device.

Monitoring issues are minimized with current technology. Elios Solar Inverters feature enhanced smart monitoring for stable, real-time remote tracking of your system's output.

8# Inverter Shutting Down at Peak Sun Hours

Possible Causes:

• Grid overload or voltage fluctuations
• Thermal shutdown due to high temperature
• System overproduction
• High DC Input Voltage (often caused by very cold temperatures, maximizing panel output)

How to Fix:

• Check the grid voltage (this is the most common cause). The inverter shuts down if the utility voltage is too high. Check your monitoring portal for a high voltage error. DO NOT attempt to adjust voltage limits yourself; this requires a certified technician.
• Improve cooling and ventilation to prevent overheating. Re-check all points in Issue #5 (Overheating). If the ambient temperature is extremely high, the inverter may be operating normally but is pushing its thermal limits.
  
• If the system over-produces and you're frequently clipping power, consider using Battery Storage Solutions to capture that excess energy.
  
• If the issue continues, consult your solar provider for adjustments.

9# Battery Not Charging in Hybrid Solar Systems

Possible Causes:

• Dead battery or faulty battery connections
• Blown Fuse or Breaker on the DC Battery Side
• Inverter settings not configured correctly
• BMS (Battery Management System) Fault
• Low solar panel output

How to Fix:

• Verify battery health and charge level. Look for an error light on the battery pack itself. If it’s a LiFePO4 battery, check the BMS status to see if it has initiated a safety shutdown.
• Ensure solar panels are generating enough power.
• Check inverter settings for proper battery charging mode. Ensure the inverter is set for the correct battery type (e.g., Lithium vs. AGM) and that the charging voltage parameters are correctly set to match the battery manufacturer’s specifications.

10#  Low Energy Yield (Reduced Output Performance)

Possible Causes:

• Aging system components
  
• Poor maintenance
• Degrading solar panels
  
• Slight Shading Creep (a nearby tree has grown)
• Degradation of DC Optimization Devices (if used).

How to Fix:

• Clean solar panels regularly to maintain efficiency.
• Update inverter firmware and software if available.
• If your Inverter is over 10 years old, its components are likely degrading. A modern, highly efficient inverter can offer higher efficiency and a full warranty.

Critical Safety Warning & Disclaimer: Consult a Professional for Solar Inverter Issues

The troubleshooting steps provided in this guide are general recommendations based on common solar inverter issues. While some minor problems can be resolved by following these suggestions, solar power systems involve complex electrical components that require professional expertise for proper diagnosis and repair.

If your solar inverter is not working correctly, we strongly advise you to contact a certified solar technician or your inverter manufacturer’s support team to prevent further damage and ensure safety.

Remember, electricity is dangerous. Always prioritize safety, and for anything beyond checking a breaker or basic troubleshooting, consult professionals for safe and professional support.

Why Choose Elios Solar Inverters for Reliable Performance?

If you’re experiencing frequent solar inverter issues, it might be time for an upgrade. Elios Solar Inverters are designed for high efficiency, durability, and seamless troubleshooting, offering:

• Smart self-diagnosis to detect and fix common errors
• Advanced cooling systems to prevent overheating
• Seamless integration with monitoring apps for real-time tracking
• Optimized performance for residential and commercial solar systems

Final Thoughts

Solar inverters are essential for a functioning solar power system, but they can encounter common problems over time. By following this troubleshooting guide, you can quickly diagnose and resolve issues without expensive repairs.

For long-term reliability and maximum energy savings, consider investing in a high-quality solar inverter like Elios Solar Inverters.