Aluminum Wire Hazards

Aluminum (AL) wire was used as a means of cutting cost on electrical installations from the late 1960s until the early 1980s. It saved about $100.00 on a 1600 sq. ft. total electric house. But at a time when minumum wage was $2.00 and that 1600 Sq. Ft. house was under $25,000 that was a sum of money to be concidered. Especially by track home builders constructing 500 to 1000 homes a year,thats $100,000 a year.

In 1970 when I entered the trade, I was hired as an apprentice on a trouble shooting truck. (AL) wire was new, unproven and just starting to show it's true nature. The service techs I was working with were convinced that as much (AL) wire that was being installed we would not want for work in our life times. The residential wiremen were just learning that you had to be a lot more careful with (AL) than with copper. The smallest scrape would let moisture in and then electrolysis would set in turning the (AL) to a white powdery corrosion like what forms on your battery terminals in your auto. Another problem that was showing up was (AL) wire was not compatable with the brass fittings used for connections with copper wire. Also the expantion and contraction rate of (AL) was much greater than copper. All of these things created loose connections and there by hot spots (fire hazards).

Residential wiremen learned to be more careful when pulling cable, a deoxidization compound came out to prevent electrolysis from dissimular metals, nickel cadmium was found to be compatable with both copper and (AL) and new (AL) rated devices with locking grids to keep screws from working loose came out. Over the next decade it was argued back and forth whether (AL) wire used for small branch circuits was the fire hazard or the big wire with heavy loads was the culprit. Many of the local building codes were changed back and forth according to the ideas and belief of the city inspectors at the time. Most of the citys in the DFW metroplex had outlawed (AL) wire in all branch circuits by 1978 but allowed it to be used as the main service feeder because the power companys used (AL) wire. In the 1982 the National Electrical Code revision virtually outlaw (AL) inside buildings.

1. Signs of trouble with (AL) increase as the situation worsens it starts with an occassional flicker in the power such as lights or equipment blinking off.

2. At the situation becomes more severe the flickering last for a longer period and a dimming or brighting of effected lights may occure.

3. As the situation enters the critical stage intermittent complete loss of power may occure, devices or sections of walls may become unexplainably warm or even hot to the touch. A humming, buzzing or arcing sound may be heard. This is a dangerous fire hazard situation, professional help should be called as soon as possible.

These symtoms may come on slowly or all at once and are not to be taken lightly.

Pigtailing is a method of improving expantion and contraction problem and dissimular metals problem. Electricians have preformed the procedure for decades using wire nuts with a nichel cadmium spring and deoxidization compound to tie a short piece of copper wire on the ends of the (AL) wire. The copper then ties to the device giving an (AL) to (AL) connection for the circuit and a copper connection for the device. This method was approved in some citys while others wanted only UL listed devices to be used. A few years ago Ideal came out with a wire nut factory treated with deoxidization compound and got it UL listed for CU/ALR connections. Now the choice is to pigtail with the Ideal connectors or use ALR rated devices.

I recommend Pigtailing because it allows you to use low cost copper rated devices and the Ideal CU/ALR wire nuts cost about the same or a little less than ALR devices. The pigtailed outlet has no accumulated load going through the device so less wear. The customer gets all new devices in the installation either way and when the device wears out then it is less expensive to replace, a savings for the customer in the long run.