How do I know there is a problem?
Know what normal looks like. Many systems have a monitor or an app showing daily production, and an off-grid system has a battery display. Compare today with similar sunny days earlier in the season, not with winter or cloudy days.
A sudden drop, an error code, a dark display or a charge controller that behaves differently are all signs to look closer. Write down the date and what you see.
Seasonal change is normal. Production drops in winter because days are short and the sun is low, and snow cover can stop an array completely. Understanding these cycles keeps you from chasing problems that are really just the calendar, and helps you size loads sensibly during darker months.
- Compare with similar weather and season
- Photograph error messages
- Note when the change began
Could shade or dirt be the cause?
Shade on even one part of a panel can cut output more than you might expect, because panels in a string are connected together. New tree growth, a new building, snow and bird droppings can all reduce production. Dust, pollen and debris add up too.
Check the array from the ground and note shadows at different times of day. Cleaning panels can be risky, so follow the maker's guidance, never climb on a roof without proper safety gear and consider hiring a professional.
Look at how the array is mounted too. Loose racking, shifted panels or damaged wiring along the roof or ground mount can follow a storm. Do not walk on or reach into the array. From the ground, look for anything hanging, cracked glass or animals nesting under panels, and report it to your installer.
- Look for new shadows in morning and afternoon
- Follow maker guidance on cleaning
- Do not climb onto a roof without safety equipment
What about batteries in an off-grid system?
Batteries wear out and need the right charging and care. Signs of trouble include batteries that no longer hold charge through the night, swollen cases, corrosion or a hot smell. Different battery types have different needs, so follow the manual for yours.
Batteries store a lot of energy and can cause burns, fire or explosion. Do not open, short or work on a battery bank without training, and ventilate battery rooms as the maker directs.
Keep a simple log of battery readings at the same time each day, such as in the morning before sunrise and late afternoon. A slow trend downward in the morning reading, over weeks, is more useful than a single number, and it gives your installer something concrete to work from.
- Check the display and readings regularly
- Look for swelling, leaks or corrosion
- Keep metal tools away from terminals
What if the inverter or controller shows an error?
Inverters and charge controllers display codes that tell you what they sense. Look up the code in the manual, write it down and note the conditions. Some are simple, such as a tripped breaker, while others signal a fault that needs service.
Resetting a device once, as the manual directs, is generally fine. Repeated errors need a qualified installer, since faults in the direct current side of a solar system can carry high voltage even in low light.
If your system has a monitoring app or portal, check that its internet connection is working before assuming production has dropped. A lost connection can make a healthy system look dead. Router changes, power outages and password changes are common reasons the data stops arriving.
- Do not open equipment enclosures
- Check the labeled disconnects and breakers
- Keep a copy of the manual near the equipment
Who should handle wiring and repairs?
Wiring, fuses, connectors, grounding and the connection to your house or the utility need a licensed electrician or qualified solar installer, and local rules often require permits and inspections. Solar wiring can remain energized in daylight and cannot simply be switched off.
If your system is grid-connected, your utility may have rules on any changes, so ask before you modify or add equipment.
- Ask your installer about the warranty
- Check what your permit and inspection records say
- Do not splice or alter wiring yourself
How do I keep it running well?
Make a seasonal routine: check for shade, look at connections from a safe distance, review production numbers and keep records of service. Trim trees as needed with proper safety and keep vegetation off the array.
Ask your installer for a maintenance schedule, and your extension office or state energy office for information on programs and guidance. Keep documents for the system in one folder.
Key takeaways
- Compare output with similar weather before deciding something is wrong.
- Shade and dirt are common and easy to spot from the ground.
- Batteries, inverters and wiring hold real hazards and need qualified help.
- Keep records and a maintenance schedule.
Sources and further reading
Last reviewed: November 12, 2026. Written by the Homestead & Small Farm Editorial Team. See our editorial policy.