It's easy to spot danger. For instance, a hiker in the woods would immediately know she was in danger when she sees a 900 pound grizzly bear stand up in front of her with his claws and fangs blazing. "Yep, that's danger," she might say to herself. But back at home, she might not recognize the dangerous electrical fire hazards lurking behind her walls. Read on to find out what they are and how to detect them.
Old Wiring
Electrical systems get outdated fast and are only designed to last 30 or 40 years. Older fuses were set up to handle about 30 amps of power, while many homes now have up to 200 amps.
How to spot it: If your house is more than 40 years old, look out for circuit breakers that trip and fuses that blow repeatedly.
How to fix it: Every case is different, so call an electrician to survey the situation in your home. He'll reccomend the past plan of action to bring your wiring up to code.
Aluminum Wiring
Back in the 1960s and 1970s, aluminum wiring was the standard. But we know now that it oxidizes and corrodes more easily than today's copper wiring and aluminum wires are linked to many electrical fires.
How to spot it: If your home was built (or an addition added) in the '60s or '70s, be on the lookout. You can check for a brand name or the word "aluminum" printed or embossed anywhere there's exposed wiring, like an attic or electric panel, but an electrician can check thoroughly for the wiring itself.
How to fix it: An electrician can keep problems at bay by installing copper connectors called "pigtails" at receptacles and breakers.
Arc Faults
Have you ever seen a spark jump through the air? Well that kind of thing can happen inside your walls and cause a fire. Any damaged wiring—whether from age or something like drilling into the wall—could create an arc fault and send an electrical current off its intended path.
How to spot it: It's tough. Like, nearly impossible.
How to fix it: We can't fix what we can't see. But the good news is that arc faults are easy to prevent against. An electrician can upgrade standard circuit breakers to arc-fault circuit interrupters (AFCI), which can sense the electrical abnormalities that arc faults create and shut down circuits before they overheat.
(Image: Providence Electric)
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Another serious hidden issue with electric service is faulty wiring. Fortunately, this is pretty easy to spot with an inexpensive circuit tester. There's an article on my blog showing how to spot bad wiring: http://tinyurl.com/2vassc6
More things to look for:
--mismatched wires (sizes/colors)
--wire nuts (should never be visible)
--paint overspray on the service panel
--frayed service entry cables
As a Home Inspector, I see these issues every day, and am amazed at how few people take them seriously.
Another potentially dangerous problem that one often sees in remodeled homes are three-prong outlets that aren't actually tied to a ground. A lot of devices need that ground connection to operate correctly, and in some cases, safely.
If you hear snap or buzzing sounds near electric wiring, if some outlets are not working and if some bulbs sometimes dim for no reason,,, have electrician check your wiring.
As an electrician there are 2 things I hate; moldings over ceiling outlets and outlets that have been covered and/or painted over.
qhartman's on the money. We're about to buy an old house, and our home inspector warned us about the same thing. He said if you don't want to rewire everything, then you can replace the offending outlets with GFCIs, which are safer than doing nothing. We're going to talk to our electrician....
If you talked to a good electrician they would tell you it's MUCH better to search out aluminum outlets and switches then to pigtail the old to new copper. It'll cost you about the same in materials, and if you know how to change an outlet it'll save you later. Plus it's a whole lot safer as it avoids the aluminum to copper heat difference, even with the compound that is suppsed to be used.
To Arkay, GFCI's will just cost you a whole lotta moula!!!! They are usually around 20$ each outlet and they are only required within 5 feet of sinks, of plumbing fixtures. Save yourself some money.
Per the electrical code, the fix for an ungrounded outlet is (1) GFCI per ungrounded circuit, preferably the first.