QUESTION: We bought our home in 1985 and plan to add several new electrical circuits and to install new light fixtures and ceiling fans into already existing circuits. The problem is that all circuits, switches, light fixtures, receptacles and appliance connections were wired with aluminum wiring components.
We know we must replace failed switches and receptacles with ones that are approved for use with aluminum wiring, but we don't know what to do about installing new copper-wired fixtures in existing circuits. A friend warned us that connecting copper to aluminum wiring could create a fire hazard. Is this true?ANSWER: Aluminum wiring is a potential fire hazard. Between 1965 and 1973 about 1.5 million homes were wired with aluminum, which at the time was approved by the National Electrical Code. Later it was found that dangerous overheating in 15- and 20-amp circuits, at some connections between aluminum wires and outlets, switches, fixtures and appliances resulted in fires.
Correcting the problem does not require rewiring the house. You can replace switches and outlet receptacles that are unmarked, or marked AL-CU, with devices that are marked CO-ALR. Or, you can use existing switches and outlets, provided you attach short copper pigtails to the ends of the aluminum wires and to the devices (aluminum-to-aluminum splices are an exception). It's also necessary to connect light fixtures and appliances with copper pigtails.
Because of the potential for a fire, it is important that copper wire pigtails be attached to aluminum wires with specially designed connectors (Wire-Nuts can be used, however, at copper-to-copper connections, such as light fixtures). The Consumer Product Safety Commission recommends using a compression-type crimp connector with heat-shrink insulation. These are called Copalum Compression Connectors. They, and the crimping tool used to install them, are made by AMP Inc., Copalum Program, MS 140-13 P.O. Box 360B, Harrisburg, PA 17105.