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David Naples

Expert Wire Electrical Services


Dangers of Aluminum Building Wiring

  Definition: Aluminum building wiring is a type of electrical wiring for residential construction or houses that uses aluminum electrical conductors.

 Aluminum building wiring typically dates between 1965 and 1974. At the time of installation it was thought to be a cost effective alternative to copper wiring. During that time period, copper prices were high due to the Vietnam War. However, it didn’t take long to discover that aluminum building wiring had a tendency to become faulty much more rapidly than copper. The U.S. Product Safety Commission reports that “You are 55 times more likely to have a connection reach fire hazard conditions in a house with aluminum wiring manufactured prior to 1972, than you are with copper”.  The properties of aluminum wiring make it dangerous to connect to outlets or devices which were not designed with aluminum wiring in mind. There were also issues related to the properties of the wire itself, making the installations with aluminum wire much more inclined to problems.  Whenever replacing a device in on an aluminum circuit, be sure to use an aluminum rated device. NEC Article 406.3 (C) states that Receptacles rated 20 amps or less and designed for direct connection of aluminum conductors shall be marked CO/ALR .

 In General, the main problem with aluminum building wiring is in the connections. Many terminations installed in the 1960s and 1970s that were properly installed continue to operate with no problems. However, when electricity passes through wires and connections the conductors heat up and expand. Aluminum wiring expands three times more than copper, and when the power is turned off, the wires cool down and contracts. The constant expansion and contraction will eventually create a gap, exposing the aluminum wire to air. The resulting oxidization causes the connections to become even hotter. Overtime, the terminations become loose, creating a fire hazard.

...So What’s the responsible thing to do concerning Aluminum Wiring?

 Proper installation of aluminum wiring includes:

1. Abrading the wires and applying a corrosion inhibitor

2. Wrapping wires around terminal screws. NOT wrapping wires around terminal screws the wrong way

3. Adequate torque on the connection screws. But, be careful as too much torque on the connection screw may cause damage to the wire, particularly with the softer aluminum wire.

 While the NEC does allow provisions for splicing aluminum and copper conductors with a rated wire connector, this practice would be considered a minimum. In general, the responsible repair to make is to replace the entire circuit. This is often a costly repair, but our concern is the safety of your home and the occupants thereof. Some insurance companies will not insure Aluminum wiring while others may be content to know that the proper connections have been made. Keep in mind the higher risk of problems with aluminum wiring, call your electrician for a professional evaluation of whether or not to replace the old out-of-date wiring.

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Ready to get the quality service you deserve? Contact Expert Wire Electrical Services today! At Expert Wire our primary goal is to bring you electrical safety and quality service with total satisfaction. Remember, leave the wiring to the Experts and have a powerful day!

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