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Independent Service

Solar Repairs & Fault Finding

System underperforming? Inverter displaying an error? Generation dropped unexpectedly? We diagnose and repair solar PV systems across Essex, Suffolk, Norfolk, Cambridgeshire and Hertfordshire — including systems we didn't install.

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Why Afta Electrical
Fully CertifiedFor all solar work
Independent serviceWe repair any brand
DC fault findingIV curve tracing available
Inverter replacementsAll major brands stocked
Est. 201510+ years solar experience

About This Service

Solar systems we didn't install

Most solar installation companies only service their own work. We service any solar PV system, regardless of who installed it — whether the original installer has ceased trading, won't respond, or is simply too far away to be practical. If your system is underperforming or has stopped working, we can help.

Solar PV faults broadly fall into three categories: inverter issues (the most common cause of complete system failure), DC-side issues (panel degradation, broken strings, connector failures or damaged cables), and AC-side issues (generation meter faults, AC isolator problems, or connection issues at the consumer unit). We diagnose all three.

Inverter replacement

Inverters are typically warranted for 5–12 years and have an expected service life of 10–15 years. Systems installed 2010–2015 (during the peak FIT years) are now commonly presenting inverter failures. We supply replacement inverters from SolarEdge, Solis, SolaX and Fronius — and can often improve on the original specification, adding panel-level monitoring or battery readiness in the process.

DC fault finding

Low generation — where the system is producing less than expected but hasn't failed outright — is often caused by DC-side faults: a broken or shaded string, a failed bypass diode in one or more panels, corroded MC4 connectors, or a cable fault in the roof void or external conduit. We use IV curve tracing to identify underperforming strings and thermal imaging to locate faulty panels without dismounting the array.

Panel replacement

Physically damaged panels (impact damage, delamination, cracked cells) and panels showing significant degradation beyond their warranted threshold can be replaced individually — it is not necessary to replace the whole array. We source matching or compatible panels and update your installation documentation to reflect the change.

System not generating since the FIT / SEG change?

Some systems on legacy FIT tariffs developed monitoring or metering issues at the time of SEG transition. If your generation meter readings seem wrong or your export data doesn't match what you'd expect, we can investigate and correct.

Any brand, any age

We service solar systems regardless of original installer or equipment brand. Manufacturer service agreements not required.

IV curve tracing

String-level performance testing identifies underperforming panels and DC faults without dismounting the array.

Thermal imaging

Faulty panels and hot cells identified non-invasively under irradiance conditions.

Inverter stock available

SolarEdge, Solis, SolaX and Fronius inverters typically available for next-working-day replacement.

Documentation updated

Replacement panels and inverters fully certified. Your installation certificate is updated to reflect the current system.

What We Fix

Common solar faults we resolve

Inverter failure

Error codes, no display, system offline. Inverter diagnosed — repaired where possible, replaced where not. Like-for-like or upgraded specification.

Low / no generation

System running but producing less than expected. IV curve tracing identifies underperforming strings. Thermal imaging locates faulty panels.

DC string faults

Open or short-circuit strings, failed MC4 connectors, damaged DC cables. Located and repaired without full panel dismount in most cases.

Panel replacement

Cracked, delaminated or significantly degraded panels replaced individually. Compatible replacements sourced. Installation documentation updated.

Monitoring system issues

Generation meter faults, WiFi monitoring failure, data logger issues. System reconnected to monitoring platform and verified against actual output.

AC isolator & circuit faults

AC isolators, generation meters and consumer unit connections inspected. Faulty components replaced and installation re-certified.

Solar system underperforming or showing errors?

Describe the symptoms — error codes, generation figures, when it started — and we'll advise on likely cause before booking a visit.
Get a Diagnosis

Common Questions

Solar repair FAQs

My inverter is showing an error code — what does it mean?
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Inverter error codes vary by manufacturer but commonly indicate: grid voltage or frequency out of range (often a temporary DNO issue, clears itself), isolation fault (earth leakage on the DC side — requires investigation), internal fault (hardware failure — may need replacement), or communication errors (monitoring connection lost). Send us the error code and inverter brand and we'll advise on likely cause before booking a visit.
My system is generating less than it used to — is this normal degradation?
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Panel degradation of 0.5–1% per year is expected — a 10-year-old system should produce roughly 90–95% of its original output under equivalent conditions. A sudden or significant drop (more than 15–20%) is not normal degradation and suggests a specific fault — a failing string, a faulty panel, or an inverter operating in a reduced-power mode. We can compare your actual generation against what the system should be producing based on irradiance data for your location.
Can you repair a system installed by a company that no longer exists?
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Yes. A significant number of solar installers that operated during the 2010–2015 FIT boom have since closed. We regularly service and repair systems originally installed by firms that are no longer trading. We'll work from the original installation certificate and any documentation you have. If documentation is missing, we can inspect the system and establish what was installed.
Is it worth repairing an older inverter, or should I replace it?
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For inverters over 10 years old, replacement is usually more cost-effective than repair — especially given the improved efficiency, monitoring capability and battery-readiness of current units. For newer inverters still within warranty, we'll attempt repair first and involve the manufacturer's technical support team where appropriate. We'll always give you both options and the honest cost-benefit analysis.
Will panel cleaning improve my system's output?
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In the UK, studies suggest soiling (bird droppings, algae, dust) rarely accounts for more than 2–5% of annual generation loss — rainfall provides sufficient cleaning on typical pitched roofs. We don't carry out panel cleaning as a service because the evidence for meaningful output improvement in UK conditions is limited. If your system is significantly underperforming, the cause is almost certainly not dirt — it's a technical fault.
What is an IV curve trace and what does it tell you?
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An IV curve trace measures the current-voltage relationship of a solar string under real irradiance conditions. A healthy string produces a characteristic curve shape. Faults — shaded panels, bypass diode failures, cracked cells, or high series resistance — produce characteristic deformations in the curve that allow us to identify the type and approximate location of a fault without dismounting panels. It's the most effective diagnostic tool for DC-side fault finding.

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Solar PV Installation

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Commercial Solar

Commercial solar repair and maintenance contracts available for business premises and larger arrays.

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Solar Repair Diagnosis Survey

Describe your fault — we'll find and fix it

Answer 7 quick questions and we'll assess your solar system issue and come back with honest advice. Takes about 2 minutes.

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Question 1 of 7
What seems to be the problem with your solar system?
Describing the symptom helps us identify the likely cause before visiting.
Question 2 of 7
What is your inverter brand?
This helps us check for known faults and ensure we bring the right diagnostic equipment.
Question 3 of 7
How old is your solar installation?
Age helps us determine whether the fault is likely warranty-related.
Question 4 of 7
Is your inverter showing any error codes?
Error codes significantly speed up diagnosis — note them down if you can.
Question 5 of 7
When did the problem start?
Knowing when helps us identify what may have triggered the fault.
Question 6 of 7
How urgently do you need this resolved?
We will do our best to prioritise accordingly.
Question 7 of 7
Almost done — where shall we send your results?
We'll review your answers and get back to you with honest, tailored advice. No hard sell, no spam.

Thank you — we'll be in touch soon!

We've received your solar repair survey. One of our engineers will review your answers and get back to you with an honest assessment — usually within one business day.

Solar system not performing
as it should?

We diagnose solar PV faults systematically — inverter issues, DC string faults, panel problems. Any brand, any age, anywhere in Essex, Suffolk, Norfolk, Cambridgeshire or Hertfordshire.

Book a Diagnosis Solar PV Installation