Fault Finding & Diagnostics
Expert ElectricalFault Finding in Cobham
Tripping circuits, flickering lights, or unexplained power loss? We use professional diagnostic equipment to find the root cause and fix it — not patch it.
Diagnosed and fixed in one visit · No guesswork · 10+ years diagnostic experience
What Is Electrical Fault Finding?
Electrical fault finding is the systematic process of identifying the cause of an electrical problem within a property's fixed wiring installation. Unlike simply resetting a tripped breaker or replacing a blown fuse, proper fault finding determines why the problem occurred and eliminates the root cause.
Common symptoms that require fault finding include circuits that trip repeatedly, lights that flicker or dim without explanation, sockets that stop working, burning smells from electrical accessories, unusual buzzing or humming sounds, and unexpectedly high electricity bills.
At Cobham Electrical Contractors, we use professional multifunction testers, insulation resistance meters, thermal imaging cameras, and circuit tracing equipment to diagnose faults accurately. Our approach is methodical — we don't guess, and we don't charge you to experiment.
We attend fault-finding call-outs across Cobham, Weybridge, Esher, Oxshott, and the wider Surrey area. Most faults are diagnosed and repaired in a single visit.
Need expert help? Get a free, no-obligation estimate or call 07935 839378 — we respond within 2 hours.
Our Fault Finding & Diagnostics Work
Why Ignoring Electrical Faults Is Dangerous
Electrical faults rarely fix themselves. A tripping circuit breaker is a safety device telling you something is wrong. Repeatedly resetting it without investigation puts you at risk:
- Intermittent faults often indicate degraded insulation — live conductors may be exposed inside walls or ceilings
- Loose connections generate heat under load, which can ignite surrounding materials and cause house fires
- A buzzing consumer unit indicates arcing — electrical discharge that degrades connections and can lead to catastrophic failure
- Flickering lights may indicate a loose neutral connection, which can cause dangerous overvoltage on other circuits
- Repeated RCD tripping left uninvestigated desensitises occupants to warnings, increasing the risk of injury when a genuine fault occurs
- Water ingress into wiring or accessories creates shock hazards that worsen progressively
How We Diagnose Electrical Faults
Symptom Assessment
You describe the problem — when it occurs, how often, and any patterns you've noticed. This initial information guides our testing strategy and helps us focus on the most likely causes.
Visual Inspection
We inspect the consumer unit, affected circuits, and relevant accessories. We look for signs of overheating, damage, moisture, rodent activity, and non-compliant previous work. Often, visual clues narrow the diagnosis significantly.
Systematic Testing
Using professional multifunction testers, we measure insulation resistance, continuity, earth fault loop impedance, and RCD operation on the affected circuits. These tests identify faults that are invisible to visual inspection.
Fault Isolation
We systematically isolate sections of the circuit to pinpoint the exact location and cause of the fault. This may involve testing individual accessories, junction boxes, and cable sections.
Repair & Verification
Once identified, we repair the fault using proper materials and methods. The repaired circuit is retested to confirm the fault is fully resolved and the installation is safe.
Why Choose Us for Fault Finding
Root Cause Resolution
We don't patch symptoms. We find the actual cause of the problem and eliminate it permanently. No repeat call-outs for the same issue.
Professional Diagnostic Equipment
Multifunction testers, insulation resistance meters, thermal imaging, and circuit tracers — the right tools for accurate diagnosis.
10+ Years of Diagnostic Experience
A decade of solving electrical faults across Surrey means faster diagnosis and fewer hours on-site. Experience saves you money.
Transparent Pricing
We explain what we've found, what needs to be done, and what it will cost before we carry out repairs. No surprises.
Most Faults Fixed Same Day
The majority of faults are diagnosed and repaired in a single visit. We carry common parts and materials to resolve issues on the spot.
Full Testing After Repair
Every repair is followed by comprehensive testing to confirm the fault is resolved and the circuit meets BS 7671 standards.
Common Electrical Faults in Cobham & Surrey Properties
The types of electrical faults we encounter most frequently vary with property age. In pre-1970s properties common across Cobham and Surrey, we regularly find degraded rubber insulation that has become brittle and cracked, exposing copper conductors. This causes insulation resistance readings to drop below safe levels and often results in persistent RCD tripping.
Properties from the 1970s and 1980s frequently have aluminium wiring in certain circuits, or a mix of old and new wiring from multiple modifications over the decades. Poor connections between different conductor materials (copper to aluminium) create high-resistance joints that overheat under load — a common cause of burning smells and discoloured accessories.
Modern properties are not immune to faults. Poor workmanship from unqualified installers, DIY modifications, and damage from renovation work (nails through cables, severed conductors from drilling) account for a significant proportion of fault-finding call-outs. Rodent damage to wiring in loft spaces and subfloor voids is also surprisingly common in rural Surrey properties.
Moisture-related faults are particularly prevalent in bathrooms, kitchens, and outdoor installations. Failed seals on bathroom extractor fans, condensation inside outdoor junction boxes, and leaking roofs allowing water to track along cables all cause earth faults that trip RCDs.
Nuisance RCD tripping — where the RCD trips without an obvious cause — is one of the most challenging fault types. It can be caused by cumulative earth leakage across multiple circuits (each within limits individually, but exceeding the RCD threshold collectively), or by appliances with inherently high earth leakage (older fridges, certain LED drivers, and some types of immersion heater).
We also attend call-outs for intermittent faults that occur under specific conditions — for example, lights flickering only when the central heating activates, or a socket that stops working when it rains. These require systematic investigation and sometimes thermal imaging to identify the cause.
We provide fault finding & diagnostics services across Cobham, Weybridge, Esher, Oxshott, Walton-on-Thames, Dorking, Godalming, Guildford, and the wider Surrey area. Read our customer reviews or view examples of our work.
Frequently Asked Questions
