Home / Microinverter Vs String Inverter Repair
Microinverter Vs String Inverter Repair
If you are deciding what to do about a failed inverter, it helps to know which kind you have. The two designs fail differently and get repaired differently. Much of what is published comes from manufacturers and sellers, so we say who is speaking.
What Stops Producing
The Enphase guide to microinverters and string inverters says string inverters connect multiple panels in series and route power to a single inverter, so the string inverter is a single point of failure: if it goes out, your home cannot use the electricity the panels produce. The EnergySage overview of microinverters says that with microinverters, if something is wrong with one unit only the panel attached to it will shut down instead of the entire system. Enphase, a microinverter maker, also says a string caps each panel at the level of the lowest producing panel. Optimizers, which Enphase says are often paired with string inverters, track peak output and regulate voltage before power reaches the inverter.
Where The Equipment Sits
EnergySage says microinverters are located on your roof, which makes maintenance more difficult, and costly if your warranty does not cover labor, while string inverters typically sit more conveniently on the side of your house. That difference affects who can reach the equipment and how long a visit takes.
How The Repair Usually Goes
| Microinverter System | String Inverter System | |
|---|---|---|
| Diagnosis | Enphase says monitoring and troubleshooting are easier, with panel level insight. EnergySage says diagnosing and fixing is often quicker than with central inverters. | Enphase lists "easy to troubleshoot at the inverter" as a pro and "harder to troubleshoot at the panel level" as a con. |
| Fix | Enphase says the fix can often be a simple swap because of the plug and play design. | Enphase says repair is usually a complete inverter replacement and can mean weeks of zero production. That is a seller's view, so ask your own service company for a timeline. |
| Warranty length | EnergySage says most microinverters are warranted for the same time as the panels they attach to, typically 25 years. The pv magazine article says 20 to 25 years. | The pv magazine USA article on residential inverter lifespans says standard string inverter warranties run 5 to 10 years, with a typical life of about 10 to 15 years, which the article attributes to EnergySage. The same article says microinverters typically carry a 20 to 25 year standard warranty. |
Enphase also states a failure rate of 0.05 percent for its IQ8 line. That is a manufacturer's own figure and we have not seen independent data, so we do not rely on it.
Questions To Ask Before A Repair
- Which type do I have, and which brand? The label on the unit and your original paperwork will say.
- Does the warranty cover labor for a roof visit, or only the part?
- If one microinverter is replaced, does the new one match my other units and my gateway?
- If it is a string inverter, is a straight replacement the plan, or is it a larger project? See Solar Inverter Replacement.
- Will you write the scope and price down before work starts?
If the company that installed your system is gone, read Installer Went Out Of Business before you call the manufacturer.
If you want a local service company to look at your system, describe it in the system check form. We name the one company before anyone contacts you.
Related: Solar Inverter Replacement, Solar Warranty Help, Installer Went Out Of Business, Solar Monitoring, Repair, And Inspection.
Get A Cleaning Quote
Tell us about your system. We match you with one local solar cleaning company and tell you who it is before anyone contacts you.
Get A Cleaning Quote