The part of your solar system that works the hardest
Solar panels are built to sit on a roof for decades with almost no moving parts. The inverter is different. It converts every bit of power your panels make from DC to AC, all day, every day the sun is up. That constant work makes it the part of a solar system most likely to need service or replacement during the life of the system.
That is not a reason to worry. It just means it helps to know how long inverters last, what trouble looks like, and what your options are when it is time for a change.
How long do solar inverters last?
It depends on the type.
String inverters. A central inverter mounted on a wall typically lasts somewhere around 10 to 15 years. Since panels often last 25 years or more, many homeowners replace a string inverter at least once.
Microinverters. These small units under each panel often carry much longer warranties, frequently 25 years, which lines up closely with the life of the panels.
Power optimizers. The optimizers on the roof usually have long warranties too, but the central inverter they feed follows a timeline closer to a string inverter.
Lifespan also depends on install quality, ventilation around a wall mounted unit, and how the system handles Colorado's swings between hot summer roofs and cold winter nights. Check your paperwork for the exact warranty on your equipment.
Warning signs of inverter trouble
Most inverter problems give you clues before the system goes fully dark. Watch for these.
Error lights or codes. Most wall mounted inverters have a status light or screen. Green is usually normal. Red, orange or a blinking light often means a fault.
System showing offline. If your monitoring app says the system or some panels are offline, the inverter may have stopped talking to the network, or it may have stopped producing.
Production drops on sunny days. Compare a clear day this month to a clear day last month or last year. A big drop with no snow or shade to explain it is worth a look.
Unusual noises. A loud buzz, clicking or a fan running harder than usual can point to an issue inside a central inverter.
A higher electric bill. If your Xcel bill jumps without a change in how you use power, your system may not be producing like it should.
One easy habit is to open your monitoring app once a week. It takes a few seconds and catches most problems early.
Sometimes it is not the inverter
A drop in production is not always an inverter failure. Other common causes include:
Snow or dirt covering panels
A tripped breaker or switched off disconnect
Lost WiFi, which stops monitoring but not production
New shade from tree growth
Wiring or connector damage on the roof
A technician can test the system and tell you exactly where the problem is before anything gets replaced.
Repair or replace?
If the inverter is still under warranty, the manufacturer may cover a repair or replacement unit. Labor coverage varies, so check the details. For an older string inverter that is out of warranty, replacing it is often the practical choice, and it is a chance to upgrade.
When it is time to replace a central inverter, you have options:
Like for like. A newer version of the same type is often the simplest swap.
Battery ready inverter. A hybrid inverter can manage both solar and battery storage, which makes adding a battery later much easier.
Panel level electronics. In some cases, switching to microinverters or optimizers makes sense, especially if new shade or a roof change has hurt production.
Can you add a battery to an existing system?
Usually, yes. How it works depends on what you have now.
With a string inverter, you may need a hybrid inverter or a separate battery inverter so the battery can charge and discharge.
With microinverters, many systems can add a battery that is designed to work with that equipment, often called AC coupling.
With power optimizers, a compatible battery inverter can often tie in directly.
On the Front Range, battery storage is popular for backup during winter storms and high wind events, and for using more of your own solar power instead of sending it to the grid. If your inverter is getting older, planning a battery and an inverter upgrade together can save a second service visit.
Local service for your inverter
Impact Energy & Roofing installs and services solar inverters and battery systems in Denver, Castle Rock, Colorado Springs and Pueblo. We work with SolarEdge and Enphase equipment and battery options from Sonnen and Generac, and we can test your current system, explain what we find and lay out your options plainly.
If your inverter shows an error, your system is offline, or production has dropped, call Impact Energy & Roofing to schedule a system check.