Finding that one weird wire behind your wall that keeps blowing fuses can be annoying and concerning. However, before you call an expensive electrician, there are several troubleshooting steps you can try yourself to locate and fix the problem. As someone who has dealt with electrical issues in my home, I want to share what I've learned about finding and repairing that pesky shorted wire without professional help.
Locating the Faulty Wire
The first step is to narrow down which wire is causing the issue. Here are some tactics I've used to systematically isolate the problem wire:
Turn Off Non-Essential Circuits
Turn off all the circuit breakers in your electrical panel one-by-one except those powering essential items like the refrigerator. If turning off a particular circuit makes the fuse blowing stop, you've identified the circuit containing the faulty wire.
Shut Off Sections of Your Home
Once you've identified the problem circuit, determine what rooms or areas of your house it powers. Start shutting off sections of your home room-by-room to further isolate the issue. For example, if the bedroom lights are on the faulty circuit, shut off the bedroom breaker. If the fuse still blows, the issue is elsewhere.
Use a Non-Contact Voltage Tester
Use a non-contact voltage tester to scan wires inside your walls. It will detect electrical current flowing through hidden wires and alert you to the live wire. Starting from the service panel, methodically scan sections of wall to track down the specific branch with the fault.
Key things to remember when scanning for the bad wire:
- Work systematically from the panel outward
- Scan up and down walls and across ceilings
- Concentrate on sections serviced by the faulty circuit
Diagnosing the Specific Problem
Once I've identified the specific wire causing issues, I diagnose the type of fault:
Short Circuit
A short circuit is when current flows directly between hot and neutral or ground wires. This is often caused by damaged wire insulation allowing contact between conductors. Shorts draw a lot of current and will quickly blow a fuse.
Loose Connection
Loose wire connections can increase resistance and heat up, eventually melting insulation and shorting. Loose connections are a major fire hazard so it's crucial to identify and fix them.
Overload
Having too many devices drawing current through an under-sized wire can lead to excessive heat buildup and melting insulation. An overload will intermittently blow a fuse as current spikes occur.
Repairing the Faulty Wiring
Here are tips for safely repairing the faulty wire without calling an electrician:
Turn Off Power at the Panel
Of course, turn off power to the circuit at the main breaker panel before doing any work. Verify it's de-energized using a non-contact voltage tester.
Inspect the Wire
Carefully open the section of wall with the bad wire and inspect for damage. Look for melting/charring, loose connections, or holes in insulation revealing bare copper.
Replace Damaged Sections
If the wire insulation is damaged, cut out the bad section and splice in a new length of wire using wire nuts. Make sure no copper is exposed.
Tighten Connections
For loose wire connections, tighten the screw terminals or replace old push-in connectors with new mechanical ones. This eliminates resistance and overheating.
Upgrade Overloaded Wires
For overloaded circuits, #12 AWG wire minimum is usually required. Consider hiring an electrician to replace overloaded wiring with larger gauge conductors.
Test Repairs
Verify the issue is fixed by restoring power and running high load devices like hairdryers to simulate heavy current draw. The circuit shouldn't trip again.
Preventing Future Electrical Fires
To avoid more electrical faults down the road:
- Use arc-fault circuit interrupter (AFCI) breakers - they detect dangerous arcs
- Don't overload circuits - check device wattages and spread out load
- Label all circuits clearly in the electrical panel
- Inspect wires for damage, loose connections, wear and tear
- Hire an electrician for upgrades to overload, shorted or damaged wiring
In most cases, that pesky wire blowing your fuses can be fixed yourself if you carefully track down and diagnose the problem, then safely make repairs. But for overloaded, severely damaged or improper wiring, always call in a licensed electrician rather than take risks. With some electrical safety know-how and diligence, you can solve the mystery of that one weird wire without blowing your whole paycheck.