Solar Repairs, Faults & Inverter Replacement
Solar not performing? Inverter fault? Wave Renewables diagnoses and fixes existing solar and battery systems across Norfolk and Suffolk - quickly, and without the runaround.
Full diagnostics before any fix.
A drop in generation is usually the inverter, not the panels. We diagnose the actual cause - a failing inverter, one underperforming panel, a tripped isolator, a wiring or connector fault, or panels that simply need a clean - and tell you exactly what needs doing, and what it costs, before touching anything. We work on any system, whoever installed it, including battery setups and systems from companies that have since gone under.
- Full system diagnosis with test equipment, not guesswork
- Solar inverter repair and like-for-like or upgrade replacement
- Panel-level and string fault finding
- Works on systems installed by other companies
What's your system doing?
Pick the closest match for a plain-English idea of what's likely going on and what we check first. It's a starting point, not a diagnosis.
Likely causes
- Failing or ageing inverter (most common after 8-12 years)
- New shading - a tree that's grown, a new extension or aerial
- One panel or string underperforming
- Dirt, moss or lichen on the panels
- An isolator switch that's been left off
What we check
Compare current output against expected generation for the array, check the inverter logs, then test each string and panel voltage to isolate whether it's the inverter, a panel, or the wiring.
Likely causes
- Grid voltage or frequency out of range (often clears itself, but repeated faults need investigating)
- Isolation / earth fault on the DC side - a damaged cable or connector
- Inverter fan or internal component failure
- Firmware fault
What we check
Read the exact fault code against the manufacturer's list, check incoming grid quality, and test DC insulation resistance to find isolation faults. Some are a reset; some are a component or inverter replacement.
Likely causes
- AC or DC isolator switched off (check the switches by the inverter and meter)
- Tripped breaker or RCD in the consumer unit
- Dead inverter - no display, no lights
- Failed generation meter or comms only (panels may still be working)
What we check
Confirm the isolators and breakers first, then whether the inverter powers up at all. If it's dead and out of warranty, replacement is usually the fix and often a chance to upgrade to a hybrid inverter ready for a battery.
Likely causes
- Home Wi-Fi changed, router replaced, or password updated
- Monitoring dongle needs re-pairing or has failed
- Manufacturer server outage (check if others report the same)
- Inverter is fine - only the reporting link is down
What we check
Re-pair the monitoring dongle to your network, check the inverter is logging locally, and confirm generation is actually unaffected. Often a 20-minute fix.
Likely causes
- Battery in a protective standby state after a firmware or comms fault
- Charge/discharge schedule or tariff settings changed
- Hybrid inverter fault affecting the battery link
- A battery module at end of life (after ~10+ years)
What we check
Read the battery management system status and error history, check the inverter-battery comms, and review the charge settings against your tariff. Restores normal operation or quotes a module/inverter replacement.
Do this now
Switch off the AC and DC isolators at the inverter, and the solar breaker in your consumer unit. Don't use the system until it's been inspected. A burning smell, buzzing, scorching or discoloured casing points to a connector, isolator or inverter fault that can be a fire risk.
What we do
Prioritise the visit, inspect the DC connectors, isolators and inverter terminals for arcing or heat damage, and make the system safe before quoting the repair.
The Solar Fault Find is a £75 call-out fee, offset against the cost of the repair if you go ahead. We diagnose the fault, explain it, and give a fixed quote; you decide whether to proceed. Norfolk and Suffolk, usually on site within a few working days.
When it's the inverter.
Inverters are the hardest-working part of a solar system and the first thing to wear out - most string inverters last 10-15 years against 25+ for the panels. Signs yours is on the way out: repeated error codes, a steady fall in generation, fan noise or rattling, or it simply not waking up in the morning. We replace like-for-like where that's the sensible option, or fit a hybrid inverter so you can add battery storage at the same time or later. Your existing panels and mounting stay exactly as they are. Brands fitted include SolaX, Fox ESS, GivEnergy, SolarEdge, Solis and Growatt.
What an inverter swap costs.
Replacing a single-phase (domestic) solar inverter up to 4kW starts at £630 inc. VAT for a 1kW unit and is capped at £875 inc. VAT for a 3.6kW dual-MPPT model. That excludes optional add-ons, upgrades to premium brands, and a surcharge for sites more than 120 miles away. You pay on the day once it's done.
- Fresh 10-year warranty on the new inverter
- Subscription-free generation monitoring included
- Fitted by a qualified electrical engineer
- Timing agreed with you upfront - no vague lead times
- No site survey needed for most jobs - assessed over the phone
Upgrading the inverter and adding panels can affect a legacy feed-in tariff (e.g. on G98) - we'll flag it before you commit.
Get an inverter quote
Repairs & faults FAQs.
Most often it's a failing inverter, new shading, one underperforming panel, or dirt build-up. We compare your output against expected generation, read the inverter logs, and test each string to find the actual cause before any work starts.
Warning signs are repeated error codes, a sudden or steady drop in generation, fan noise or rattling, or the inverter not switching on. Most inverters last 10-15 years - if yours is older and underperforming, replacement is often the fix.
Yes. We diagnose and repair existing solar and battery systems regardless of who installed them - including systems from installers who've since gone out of business.
The Solar Fault Find is a £75 call-out fee, offset against the cost of the repair if you go ahead. We diagnose the problem, explain the cause and give you a fixed quote before any work starts. There's no obligation to book the repair.
Yes - that's the most common repair. The panels and mounting are untouched. It's also a good moment to move to a hybrid inverter if you're thinking about a battery.
If there's a burning smell, buzzing, scorching or a hot inverter casing, yes - switch off the AC and DC isolators and the solar breaker, and don't use it until it's inspected. For a gradual drop in output it's fine to leave it running until it's been looked at.
Inverter lifespan and replacement-cost figures are indicative, from the Energy Saving Trust and manufacturer data (September 2026).
Last reviewed September 2026.
Something not working right?
Get in touch for a straight, no-pressure diagnosis - £75 call-out, offset against the repair.