Short answer: First check the solar isolators and the breaker in your consumer unit are on, note any error code, and read the generation meter on a sunny day. If it still isn't producing, the inverter needs testing. Inverters usually need replacing after about 12 years, and a replacement doesn't end a Feed-in Tariff.
First checks you can make safely
Before calling anyone, work through these. None of them involve opening equipment.
- Look at the inverter screen or lights and write down any error code. Take a photo.
- Check the AC isolator near the inverter and the DC isolator, often next to it or in the loft, are switched on.
- Check the solar breaker in your consumer unit hasn’t tripped.
- On a bright day, read the generation meter, then read it again an hour later. If it hasn’t moved, the system isn’t producing.
- If the manual gives restart steps, follow them. Don’t open the inverter or disconnect any cables.
If a switch trips again after you reset it, leave it off. That usually points to a fault that needs testing.
What it usually means
A blank screen with no lights often means no power is reaching the inverter, from a tripped breaker or isolator, or an internal failure. A grid error or voltage fault can clear on its own when the grid settles, but if it keeps coming back it needs looking at. An isolation or earth fault usually points to a problem on the panel side, such as damaged cable or a failing connector, and needs testing rather than resetting. If birds have been nesting under the panels, cable damage is worth checking first.
Inverter showing an error code?
Send a photo of the screen with your postcode and we will call you back.
Repair or replace
Some faults are outside the inverter and can be fixed without replacing it. Others mean the inverter itself has failed. The Energy Saving Trust says to expect to replace an inverter after about 12 years, while panels last 25 years or more (Energy Saving Trust). On a system from the early 2010s with its original inverter, replacement is usually the sensible choice.
A replacement has to suit the panels: their number, how they are wired and the voltage they produce. It is also the moment to decide about a battery. A hybrid inverter costs more than a like-for-like swap but lets a battery go in later without changing the inverter again.
Your Feed-in Tariff
Ofgem says you can repair or replace some or all of the generating equipment without affecting your accreditation, provided the installation still meets the scheme rules and isn’t removed altogether (Ofgem). For most home systems you only need to tell your FIT licensee what changed. Keep the paperwork from the replacement.
What it costs in Derby
Checkatrade lists solar servicing and repair in Derby at £224 to £483, averaging £325 (Checkatrade). That covers finding and fixing common faults. A replacement inverter costs more and is priced separately. Solar panel repair explains how a visit works.
Bottom line
Check the isolators and the consumer unit, note any error code, and read the generation meter on a sunny day. If the inverter still won't produce, it needs testing. On an older system a replacement is often the right fix, and it doesn't affect your Feed-in Tariff if the system still meets the rules. Call 01332 919162, 9am to 7pm, 7 days.