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NAPIT Registered · Systematic Diagnosis

Electrical Fault Finding

Tripping RCDs, dead circuits, flickering lights, unexplained high consumption — we diagnose and fix electrical faults across Essex, Suffolk, Norfolk, Cambridgeshire and Hertfordshire. No guesswork.

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Why Afta Electrical
NAPIT RegisteredQualified diagnostic work
Systematic approachTest, not guess
Same-day repairMost faults fixed on first visit
No call-out rouletteFixed hourly rate, transparent
Est. 201510+ years of diagnosis

About This Service

Diagnose first, fix second

Electrical fault finding is a skill that requires knowledge of how electrical systems behave under different fault conditions — not just a process of swapping components until the problem goes away. We use calibrated test equipment to measure insulation resistance, earth loop impedance, RCD performance and voltage drop before concluding anything about the cause of a fault.

Common faults we attend include nuisance RCD tripping, dead ring main circuits, intermittent power loss, circuit breakers that won't reset, overloaded circuits, and unexplained high electricity bills caused by leakage or appliance faults. In all cases, we establish what is actually happening before deciding what needs to be done.

Nuisance tripping

An RCD that trips repeatedly — particularly at night, in damp weather, or when a specific appliance is used — is almost always indicating a real leakage path, not a faulty RCD. We measure the actual leakage current on each circuit systematically, identify the circuit and the appliance or cable section causing the issue, and resolve it. Replacing the RCD without diagnosis will not fix the underlying problem.

Intermittent faults

Intermittent faults — problems that come and go — are the most demanding to diagnose because they can't always be reproduced on demand. We use data loggers and thermal imaging where appropriate, and work through the most likely causes methodically. Intermittent faults are often caused by loose connections, corroding terminations, or cables with marginal insulation that only breaks down under load or in certain temperature conditions.

We fix what we find

Unlike some inspection-only services, we carry sufficient stock to resolve most common faults on the first visit — replacement sockets, MCBs, RCBOs, junction boxes, cable sections and connectors. Where a larger repair is needed (rewiring a circuit, replacing a consumer unit), we'll quote on site and agree a return visit.

Intermittent faults and thermal imaging

For suspected overheating connections or faults only present under load, we use thermal imaging cameras to identify hot spots in consumer units, junction boxes and accessories — without invasive dismantling.

Calibrated test equipment

Insulation resistance, earth loop impedance, RCD trip time and leakage current measured — not estimated.

Thermal imaging available

Hot connections and overloaded conductors identified non-invasively. Particularly useful for intermittent or load-dependent faults.

Most faults fixed first visit

We carry common replacement parts. Sockets, MCBs, RCBOs, junction boxes and short cable sections resolved on the day.

Transparent hourly rate

No hidden call-out fee that inflates the bill. Quoted rate includes travel within our service area.

Certificate issued on repair

Where repair work constitutes a notifiable addition or alteration, a minor works certificate or EIC is issued as appropriate.

Common Fault Types

Faults we diagnose and fix

Tripping RCD / RCBO

Systematic leakage current testing across all circuits. Faulty appliances, damaged cables and moisture ingress all identified and resolved.

Dead circuits

Circuit breakers that won't reset, ring mains with open circuits, cables damaged by drilling or rodents. Located and repaired or replaced.

Flickering lights

Loose connections, failing dimmer switches, neutral faults and lamp incompatibility all diagnosed. LED driver failures distinguished from wiring issues.

Overloaded circuits

High consumption, warm cables or warm accessories investigated. Load assessment and circuit remediation — sometimes just a circuit addition, not a rewire.

Intermittent power loss

Power that comes and goes, or faults that only appear under load. Data logging and thermal imaging used where direct testing isn't conclusive.

Post-EICR remedials

FI (Further Investigation) items from a previous EICR — faults requiring investigation that couldn't be confirmed during the periodic inspection.

Electrical problem you can't get to the bottom of?

Describe the fault in as much detail as you can — when it happens, what it affects, what you've already tried. We'll advise before you commit to a visit.
Describe Your Fault

Common Questions

Fault finding FAQs

My RCD keeps tripping — what's causing it?
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RCDs trip when they detect a leakage current to earth exceeding their rated threshold (typically 30mA). Common causes include faulty appliances (particularly white goods, washing machines, dishwashers), damaged cable insulation, moisture in outdoor or bathroom circuits, and ageing wiring with degraded insulation. We measure the leakage on each circuit systematically to pinpoint the source — it's almost always a real fault, not a faulty RCD.
A circuit breaker keeps tripping — is this the same problem?
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Not necessarily. A circuit breaker (MCB) trips on overcurrent — too much load. This can be caused by too many appliances on one circuit, a cable or appliance fault causing a short circuit, or a failing MCB itself. We'll measure the actual fault current and load to determine whether it's an overload issue, a short circuit, or a faulty protective device.
Can you find a fault without knowing where the cable runs?
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Yes. We use insulation resistance testing to confirm whether a fault is in a cable or at a termination, and cable tracing equipment to locate cable routes. For open-circuit faults, time-domain reflectometry can sometimes locate a break in a cable without lifting floorboards. We minimise invasive investigation wherever possible and explain what access we'll need before starting.
How much does fault finding cost?
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We charge on a time-and-materials basis for fault finding work. We'll give you an hourly rate and an estimate of the likely time required based on your description. Some faults are found quickly; others take several hours. We'll update you if the diagnosis is taking longer than expected before incurring additional time. Repair materials are charged at cost.
My lights flicker only on certain circuits — is this dangerous?
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Flickering on a single circuit is most commonly a loose connection or failing switch — a potential fire risk if left. It can also be LED driver incompatibility with older dimmer switches (not dangerous, but annoying). We'll test the circuit, check connections at the consumer unit, junction boxes and accessories, and advise on the cause before recommending any repair work.
Do I need an electrician, or can I fix this myself?
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Some basic checks are safe for a householder — unplugging appliances to identify a faulty appliance tripping an RCD, for example. However, any work beyond changing a plug or replacing a like-for-like socket requires an electrician to certify, and any work involving the consumer unit, meter tails or fixed wiring should always be carried out by a qualified electrician. If you're unsure, contact us — we'll advise honestly whether a visit is needed.

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Electrical Fault Diagnosis Survey

Describe your fault — we'll diagnose it fast

Answer 6 quick questions and we'll assess your fault and respond with honest advice. For emergencies, indicate urgency in Q5.

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Question 1 of 6
What type of electrical fault are you experiencing?
Describe the main symptom — we'll diagnose the likely cause.
Question 2 of 6
How long has the fault been present?
Recent faults are often simpler to trace — ongoing issues can indicate deeper problems.
Question 3 of 6
How much of the property is affected?
This helps us understand whether it's a circuit, zone or whole-installation issue.
Question 4 of 6
What type of property is it?
Property type affects access, circuit layout and typical fault patterns.
Question 5 of 6
How urgently do you need this resolved?
Burning smells or complete power loss should be treated as emergencies.
Question 6 of 6
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 fault description. One of our engineers will review your answers and get back to you — usually within a few hours for urgent faults.

Electrical fault you can't
get to the bottom of?

Describe your problem and we'll advise whether a site visit is the right next step. No unnecessary call-outs — honest advice before you commit to anything.

Get in Touch Book an EICR