Electrical tips and safety

Is the electrical wiring in your house safe?


Most likely it is but if your home was built tween approximately 1965 and 1973 you have aluminum wiring.  Aluminum wiring was often substituted for copper branch circuit wiring in residential systems.  This was due to the sudden rise of the price of copper.  Aluminum is a good conductor, and at the time seemed like a reasonable choice.  Unfortunately homes built with aluminum wiring are 55 times more likely than those with copperAluminum Wiring

Aluminum Wiring is it dangerous to havewiring to overload and increase the possibility of a fire due to the inherent qualities of the metal.  This risk increases every year.  Last year more than 24,000 home fires were caused by faulty electrical wiring.




What to Watch For

The potential signs of electrical overheating to watch out for are:

  1. Flickering or dimming lights: If you notice this this could be a sign that there is a problem with electrical wiring including a loose connection from aluminum wiring or the overloading of your circuits.  Every year we get more and more electrical devices which puts a larger burden on your electrical system.  Having aluminum wiring makes this even worse.
  2. Burnt or discolored outlets: If you notice outlets that are burnt or discolored this could be a another sign of the problem with electrical wiring and should be checked.  A wire to the outlet could be loose or shorted.  While usually this would cause your circuit breaker refused to trip, sometimes it is just low enough not to.
  3. Unusual odors: If you detect a burning smell then you should immediately turn off the circuit if possible and contact an electrician.  This, as always, would be a good time to remember your smoke detectors.



Aluminum Wiring Arcing

Aluminum Wiring Arcing


Some of the risks of aluminum wiring include:

  1. Overheating: Aluminum wiring is a higher rate of expansion and contraction than copper wiring which can cause the wiring to become loose over time.  Loose connections can lead to overheating and arcing which can cause electrical wires
  2. Oxidation: aluminum wiring is more prone to oxidation than copper wiring which can cause the wiring to deteriorate over time.  As it does to be more prone to overheating and fire risk
  3. Flexibility: aluminum is not as ductile or flexible as copper wiring hence is easily cracked and will not give a good connection. This creates a higher resistance which can again lead to overheating
  4. Incompatibility with some devices: some electrical devices such as switches and outlets are designed for use with copper wiring and may not be compatible with aluminum wiring.  Using these can also increase the risk of overheating and create a fire risk
  5. Difficulty in repair and maintenance: repairing and maintaining aluminum wiring can be more challenging than copper wiring as it requires specialized tools and techniques.  Aluminum is soft and highly sensitive to compression.  After a screw has been over tightened on lumen wiring the wire will continue to deform which can cause a loose connection and increase electrical resistance in that location.  If aluminum wiring is damaged or needs repaired is important to hire a qualified electrician to do the jo
  6. Contractors: The engineers at Middle Tennessee Inspections work with some great contractors.  Here is out list  Contractor List
Burnt Outlet

Aluminum wiring can cause overheating


Is my House Unsafe?

Having aluminum wiring does not mean that the house is at a medically unsafe as there are many ways to mitigate risks associated with aluminum wiring.  If your house has aluminum wiring it is recommended to have inspected by qualified electrician determined if any remedial actions are necessary.

  1. Installing copper pigtails: Copper pigtails can be installed at the ends of the aluminum wiring and connected to the copper wiring in the switches, outlets, and other electrical devices. This can help to reduce the risk of overheating at the connection points.
  2. Installing specialized connectors: There are connectors called “CopAlum crimps”  that are specifically designed for use with aluminum wiring. These connectors can help to ensure a secure and safe connection between the aluminum wiring and the electrical devices but require a special tool.  Anti-oxidant paste is also required.
  3. Replacing the aluminum wiring: In some cases, it may be recommended to replace the aluminum wiring with copper wiring. This can be a more expensive option, but it can provide greater peace of mind and reduce the risk of electrical fires.
  4. Make sure GFCI and AFCI up to date:  As with any type of wiring make sure that you are fully protected.  Even they were not required in 1973 you should make sur that you have GFCI and AFCI protection.  We even have a blog –   Arc Fault
  5. It’s important to note that any remedial actions should be undertaken by a qualified electrician who has experience working with aluminum wiring. They will be able to recommend the best course of action for your specific situation, and ensure that the work is done safely and up to code.


CopAlum Connectors

CopAlum Connectors

CopAlum Connectors installed



Identifying Aluminum Wiring

Aluminum wires are a silver-ish color and shiny.  Copper wiring has an orange-ish color.  Crayola calls it copper .  Often the word” aluminum” or the letters “AL” may be embossed or printed on the wire insulation.  If your house was built between 1965 and 1973 there is a very good chance you have aluminum wiring.

Aluminum Wiring Label

Aluminum Wiring Label



Breaker with aluminum wiring

Breaker with aluminum wiring




Circuit panel with aluminum wiring

Circuit panel





Having aluminum wiring in your home does not necessarily mean that you will have a fire, but you should be aware, check, and prepare.  The inspector engineers at Middle Tennessee Inspections are InterNACHI Certified and can quickly let you know if you have aluminum wiring.


Aluminum Wire Compare

Aluminum Wire Comparison





What are AFCIs? 

An arc-fault circuit interrupter (AFCI) or arc-fault detection device (AFDD) is a circuit breaker or receptacle that breaks the circuit when it detects the electric arcs that are an indicator of loose connections in electrical wiring. Loose connections, which can develop over time, can sometimes become hot enough to ignite house fires. An AFCI selectively distinguishes between a harmless arc (incidental to normal operation of switches, plugs, and brushed motors), and a potentially dangerous arc (that can occur, for example, in a lamp cord which has a broken conductor).

What are AFCI testers or indicators? 

AFCI tester indicators (sometimes called AFCI testers) are portable devices designed to test AFCI functionality. They create waveform patterns similar to those produced by actual arc faults, thereby causing working AFCIs to trip. AFCI indicators are considerably larger and more expensive (by several hundred dollars) than  ground-fault circuit interrupter (GFCI) indicators and are of questionable effectiveness. For these reasons, they are not used as widely as GFCI indicators.

Why are AFCI indicators important?

While an AFCI circuit breaker comes with a test button that performs a role similar to a portable AFCI indicator, this button cannot test for arc faults within individual portions of the branch circuit. An AFCI indicator, however, can test any individual receptacle within the branch. InterNACHI inspectors should use AFCI indicators to inspect receptacles observed and deemed to be AFCI-protected.

How do they work?

AFCI indicators should be inserted directly into the receptacle. Some AFCI indicators offer a number of testing options. This indicator creates eight to 12 pulses of 106 to 141 amp charges in less than a second which should be recognized by the AFCI as a dangerous arc and cause it to open the circuit that it serves. The indicator can also test for nuisance tripping, the annoying tendency of an AFCI to open its circuit when it detects a safe, shared neutral connection. For this test, it produces a 300mA arc that should not cause the AFCI to trip. Some AFCI indicators conveniently incorporate a GFCI indicator into their design.

AFCI indicators are somewhat larger than GFCI indicators but they are operated in the same way. An inspector simply inserts one into a receptacle and navigates the menu in order to produce the desired electric current. The user will know that the circuit in question has been tripped if the AFCI device loses power. If this occurs following an AFCI test, the AFCI is functioning properly. The user should then go to the electrical panel to reset the AFCI breaker. If the test results in the failure of an AFCI breaker to open the circuit, then a qualified electrician should be contacted.

How effective are they? 

It is important to understand the distinction between an AFCI indicator and the test button on an AFCI device. The latter produces an actual arc fault and can be relied upon to assess the functionality of the AFCI. An indicator, by contrast, creates waveforms that are not true arcs but are characteristic of them and are thus not a completely reliable measure of an AFCI’s functionality. As a result of this distinction, an indicator might not cause a perfectly functional AFCI to trip. Although commonly called testers, it is more appropriate to refer to them as indicators, despite terminology that often appears in AFCI “tester” user guides.

Underwriters Laboratories, a product-testing organization that develops product standards, requires AFCI indicators to include the following information detailing this limitation in their product manuals:

CAUTION:  AFCIs recognize characteristics unique to arcing, and AFCI indicators produce characteristics that mimic some forms of arcing. Because of this, the indicator may give a false indication that the AFCI is not functioning properly. If this occurs, recheck the operation of the AFCI using the test and reset buttons. The AFCI button test function will demonstrate proper operation.

This caution implies that an AFCI is working properly if the indicator causes it to trip, but the reverse is not necessarily true.  An AFCI that does not trip as a result of an indicator may actually be perfectly fine. The test button on the circuit interrupter can be used to confirm its malfunction in the event that the indicator does not cause it to trip. Manufacturers claim that their AFCI indicators provide a universal method to test AFCIs that are produced by different companies.



AFCI indicators help ensure that AFCIs are properly monitoring the circuits that they serve for dangerous arc faults. These devices create electrical waveforms characteristic of those produced by an actual arc. As their effectiveness has been debated, they should be viewed as a complement to the test button on an AFCI, rather than a substitute.

Original Article Copied with Permission from InterNACHI – https://www.nachi.org/3.htm