Growatt Inverter Repair and Fault Codes
An error code on the screen, No AC Connection, or a blank display? We’re a certified Growatt installer, and we diagnose and repair Growatt inverters from any installer, across England, Wales and Scotland.
Repairs you can rely on
- Certified Growatt installer
- MCS registered
- NAPIT registered
- TrustMark approved
- Fully insured
- Any installer’s system
- In-house engineers — no subcontractors
Call us on 0800 156 0191
Monday to Friday, 9:00am–5:00pm
Is this what you’re seeing?
An Error or Warning code on the inverter’s screen
No AC Connection on the display
PV Isolation Low, or another insulation fault
The Growatt monitoring app shows the inverter offline
A blank display, even in daylight
Zero output on a bright day
The inverter switches off and on through a sunny day
The solar breaker in the consumer unit keeps tripping
Write down the code exactly as it’s shown, including whether it says Error or Warning. On Growatt inverters the same number can mean different things.
Call 0800 156 0191 or use the fault finder further down this page. If the solar breaker keeps tripping, leave the system switched off until an engineer has looked at it.
Common Growatt faults
Growatt inverters show faults as numbered Error and Warning codes. The word matters: on the same inverter, Error 202 and Warning 202 are different faults. The number can also mean different things on different Growatt ranges, so the model name on the inverter’s label helps us too. We install Growatt systems as well as repairing them, so we know how these faults show up.
PV insulation faults
Error 203, PV Isolation Low, means the insulation between the panels or their wiring and earth has dropped too low. Growatt’s checks include the earthing, whether the DC breaker has got wet, and measuring the panel wiring’s resistance to earth, which is work for an engineer.
Panel voltage too high
Error 202 on MIN, MIC and SPH inverters means the voltage coming from the panels is above the inverter’s maximum. Growatt’s advice is to switch off the DC switch straight away and have each string’s voltage checked. It can point to a string that isn’t suited to that inverter, which needs an engineer to put right.
No AC connection
No AC Connection (Error 302) means the inverter can’t detect the mains supply. Check that there isn’t a power cut and that the solar breaker in your consumer unit is on. If it is and the message stays, the AC wiring or the inverter needs testing.
Older and three-phase Growatt inverters
Older Growatt TL and MTL inverters use different codes, such as Error 116 (a memory fault) and Error 117 (a relay fault), where a restart sometimes clears the problem. Growatt’s three-phase MOD and MID inverters add warnings such as Warning 200, a PV string fault.
Repair or replace?
We always diagnose first: many Growatt faults are in the wiring, connectors or settings rather than the inverter. If replacement is the better option, you get a clear written quote before any work starts. Read more about inverter repair and replacement, how we find faults across the whole system, or the Growatt systems we install.
Growatt error codes and what they mean
The meanings below come from Growatt’s user manuals for the MIN TL-X, MIN TL-XH, MIC TL-X and SPH ranges, the three-phase MOD and MID ranges, and Growatt’s troubleshooting guide for older TL and MTL inverters. Each code shows the ranges it applies to.
| Code | What it means | What to do |
|---|---|---|
| Error 202 (MIN, MIC, SPH, MOD) | PV Voltage High: the panel voltage is above the inverter’s maximum | Growatt advises switching off the DC switch straight away. Then call an engineer to check the string voltages. |
| Error 203 (MIN, MIC, SPH, MOD) | PV Isolation Low: an insulation fault between the panels or wiring and earth | Call an engineer to test the earthing and the panel wiring. |
| Error 302 / No AC Connection (MIN, MIC, SPH) | The inverter can’t detect the mains supply | Check for a power cut and that the solar breaker is on. If the message stays, call us. |
| Error 116 (older TL and MTL) | The inverter couldn’t read or write its memory chip | Restart the inverter as its manual describes. If it keeps happening, call us. |
| Error 117 (older TL and MTL) | A fault in the relay circuit | Restart the inverter as its manual describes. If it persists, call us. |
| Warning 200 (MOD and MID three-phase) | PV string fault | Call an engineer to check the panels and string wiring. |
| Warning 201 (MOD and MID three-phase) | A fault at the PV string or PID quick-connect terminals | Call an engineer to check the terminal wiring. |
When to call an engineer
Call us if you see any of these:
- Error 202 or Error 203, even if the inverter restarts
- No AC Connection when there’s no power cut and the breaker is on
- Error 116 or 117 that comes back after a restart
- Any code that isn’t in the table
Growatt’s manuals say electrical work on the inverter must be done by qualified people. Beyond switching off as the manual advises, never open the inverter or disconnect its cables yourself.
Call 0800 156 0191 or use the fault finder below.
Why L&R Renewables
Any installer’s system
It doesn’t matter who fitted your Growatt inverter or whether they’re still trading.
Certified, in-house engineers
We’re a certified Growatt installer, MCS and NAPIT registered and TrustMark approved, and our own engineers carry out every job.
Honest about repair versus replacement
If a repair will do the job, that’s what we recommend.
England, Wales & Scotland
We cover England, Wales and Scotland.
Frequently asked questions
What does Growatt Error 202 mean?
On Growatt MIN, MIC, SPH and MOD inverters, Error 202 means PV Voltage High: the voltage from the panels is above the inverter’s maximum. Growatt advises switching off the DC switch straight away. An engineer then needs to check the voltage of each string.
What does No AC Connection mean on a Growatt inverter?
It means the inverter can’t detect the mains supply. First check that there isn’t a power cut and that the solar breaker in your consumer unit is switched on. If both are fine and the message stays, call us, because the AC wiring or the inverter needs testing.
Are you a certified Growatt installer?
Yes. We’re a certified Growatt installer. We repair Growatt inverters on systems fitted by any installer, as well as fitting new Growatt systems.
My installer has gone bust. Can you still help?
Yes. We don’t need the original installer to be involved, and we provide the certification and documentation for any new inverter we fit.
Do you cover my area?
Our engineers cover England, Wales and Scotland. Call 0800 156 0191 or tell us your postcode in the fault finder and we’ll confirm cover for your area.
Related pages
Solar inverter repair
Repair and replacement for every major inverter brand.
Solar panel repair
Diagnosis and repair for the whole system, from any installer.
Growatt battery storage and inverters
Growatt systems designed around your home and fitted by our engineers.
Tell us what your Growatt inverter is doing
Answer four quick questions — including the error code — and leave your details, and we’ll call you back to arrange a visit. Prefer to talk? Call 0800 156 0191, Monday to Friday, 9:00am–5:00pm.
Solar fault finder
What’s happening with your system?
What make is your inverter?
Roughly how old is the system?
Where is the property?
Leave your details and we’ll be in touch to book your initial visit.
We’ll ring you to talk it through and arrange a convenient time. Your answers above go with your enquiry, so you won’t have to repeat them.
We’ll talk through what’s happening and book your initial visit. If it’s urgent, call 0800 156 0191.
Rather talk now? Call 0800 156 0191 — free from UK landlines and mobiles.
You can also reach us through our contact page.