Problem 1: The Generation Numbers Are Lower Than Expected
This is the most common complaint. Someone buys a 5kW system but only sees 3.5kW on a sunny afternoon. They think something is broken.
Usually, nothing is broken.
Why it happens
Solar panels are rated under perfect laboratory conditions. That means 25 degrees Celsius, direct sunlight at a perfect angle, no dust, no clouds, and brand new panels. Real roofs are not laboratories.
On a hot day, panel temperatures can reach 60 to 70 degrees Celsius. Hot panels produce less power. You lose about 0.3 to 0.5 percent for every degree above 25 degrees. On a 35-degree day, that is a 3 to 5 percent loss just from heat.
Then there is dust. A thin layer of dust on panels can reduce output by 5 to 10 percent. Bird droppings or leaves cause even bigger losses on the panels they cover.
Then there is the inverter itself. No inverter is 100 percent efficient. Our microinverters run at 99.5 percent peak efficiency. String inverters are usually 97 to 98 percent. That is another 2 to 3 percent loss.
Add it all up, and a 5kW system producing 3.5 to 4kW on a real sunny afternoon is actually normal.
What to check first
Open your monitoring app on a clear day around noon. Look at the panel-level data if your system has it. If one panel is producing much less than others, go look at it. Maybe a bird left a mess. Maybe a tree branch now casts shade. Maybe a leaf is stuck on the glass.
Clean the panel with water and a soft brush. No soap. No pressure washer. Just water and gentle wiping. You would be surprised how often this fixes the "problem."
When to call for help
If every panel is producing far below expected, even after cleaning, there might be an issue with the inverter or the grid connection. Check if your inverter shows any error codes in the app. If it does, look up the code in the manual or call your installer.
If the numbers seem low but consistent across all panels, it is probably just real-world conditions. Your system is likely fine.
Problem 2: The Wi-Fi Connection Keeps Dropping
Modern inverters and microinverters use Wi-Fi to send data to the cloud. When the connection drops, your app shows outdated information or nothing at all. The system still generates power. It just stopped telling you about it.
Why it happens
Inverters are usually installed in garages, utility rooms, or on outside walls. These are not great places for Wi-Fi. Metal roofs block signals. Concrete walls block signals. Distance from the router matters.
For microinverters mounted on the roof under panels, the signal has to travel through the panel, through the roof material, through walls, and then to your router. That is a long path with lots of interference.
What to check first
Open your phone and stand next to the inverter. Check your Wi-Fi signal strength. If you only have one or two bars, that is your problem.
Move your router closer if possible. Or add a Wi-Fi extender or mesh node between the router and the inverter. Many homeowners solve this with a $30 extender.
Also check your router settings. Some routers automatically switch between 2.4GHz and 5GHz bands. Inverters almost always use 2.4GHz because it travels farther and penetrates walls better. If your router keeps pushing the inverter to 5GHz, the connection will drop. Set up a separate 2.4GHz network for your solar equipment if your router allows it.
When to call for help
If you have strong Wi-Fi signal at the inverter but the app still shows no data, the problem might be with the inverter's Wi-Fi module or the cloud server. Try power cycling the inverter. Turn it off, wait 30 seconds, turn it back on. If that does not work, contact support.
For microinverters with poor signal, some models support external antennas or wired connections. Check your product specs. Our CHUHAN microinverters use Wi-Fi but we can advise on signal boosting options for difficult installations.
Problem 3: The Inverter Is Making Noise
Inverters are supposed to be quiet. Not silent, but quiet. When they start making new or loud noises, people get nervous.
Why it happens
First, figure out what kind of noise you are hearing.
A low hum or buzz – This is normal. Inverters have transformers and electronic components that vibrate slightly when power flows through them. The hum is usually louder when the inverter is working hard on a sunny afternoon. At night or on cloudy days, it might be barely audible. This is not a problem.
A clicking sound – Some inverters click when they connect to or disconnect from the grid. This happens in the morning when the sun comes up and the inverter starts, and in the evening when it shuts down. A few clicks per day is normal. Constant clicking is not.
A fan noise – String inverters and larger microinverters have cooling fans. The fan spins faster when the inverter gets hot. On a hot day, you will hear the fan running. That is normal. What is not normal is a grinding or rattling sound. That usually means a fan bearing is failing or something is stuck in the fan.
A high-pitched whine – This can indicate a failing component or a problem with the grid frequency. If you hear a high-pitched whine that changes with the weather or time of day, call your installer.
What to check first
For fan noise, check if anything is blocking the vents. Dust buildup can make fans work harder and fail sooner. Clean the vents with compressed air if you have it.
For humming, compare the noise level to what you remember from the first week after installation. If it is the same, it is fine. If it has gotten noticeably louder, something might be loose inside.
When to call for help
If you hear grinding, rattling, constant clicking, or a high-pitched whine, call your installer. Do not open the inverter yourself. Inverters contain high-voltage components that can kill you even when the system is off. Leave it to the professionals.
Most of these issues are covered under warranty. Our inverters come with a standard warranty, and we can help coordinate replacements if needed. But first, have a local electrician or installer diagnose the problem. They can tell you whether it is a simple fix or a replacement issue.
A Few Final Thoughts
Most "problems" with solar inverters are not problems at all. They are normal behavior that nobody explained at installation.
Low generation on a hot day? Normal.
Quiet humming from the inverter? Normal.
Wi-Fi drop once a month? Annoying, but normal for consumer-grade home networks.
The real problems – failed fans, failed Wi-Fi modules, complete shutdowns – are rare. And when they happen, they are usually covered by warranty.
If you have a Wenzhou Chuhan inverter and you are not sure whether something is normal or not, reach out. Send us a message through our website at www.chinachuhan.com. Describe the issue. Attach a screenshot from your app or a recording of the sound if you can. We will tell you what is going on.
We would rather answer ten "is this normal?" questions than have one customer worry for months about a system that is working just fine.
About Wenzhou Chuhan Technology CO,.LTD
Founded 15 years ago, Wenzhou Chuhan Technology CO,.LTD focuses on the investment, construction, operation, and renovation of new energy, microgrids, and zero-carbon parks. The company provides design solutions and services for DC-side products including charging piles, energy storage systems, inverters, and photovoltaics. Wenzhou Chuhan holds certifications including CCC, CB, TUV, KC, and SAA for power electronics, with operations spanning new energy, photovoltaics, energy storage, and charging.
For more information, visit www.chinachuhan.com
