Solid single strand aluminum electrical wiring, once heralded as a modern solution to rising copper costs, has a complicated history marked by initial enthusiasm, confusion, subsequent problems, and ongoing concerns. This article explores the history and inherent dangers of using solid single strand aluminum for electrical wiring.

History of Solid Core Aluminum Wiring

The use of aluminum wiring in residential construction gained prominence between 1965 and 1973. The backdrop to this shift was a significant increase in copper prices, driven by rising demand and inflationary pressures. Aluminum, being more abundant and cheaper, presented itself as a viable alternative for electrical wiring.

Aluminum wiring was not a new concept; it had been used in power transmission and distribution for decades due to its favorable properties such as lightweight and conductivity. However, its application in residential electrical systems was relatively novel. Manufacturers quickly adapted aluminum for use in standard electrical systems, producing wiring that was similar in size to traditional copper wires.

Initial Enthusiasm

The initial reception of aluminum wiring was positive.  As a “new technology”, homes built with aluminum wire were required to have Underwriter Laboratories (UL) listed circuit breakers with CO-ALR or CU-AL compatible labeling.

Builders and electricians appreciated the cost savings and the ease of installation, as aluminum is more pliable than copper. It was seen as a forward-thinking solution that could maintain affordability in the housing market without compromising on the electrical infrastructure’s integrity.

Emergence of Problems

Despite the initial enthusiasm, problems began to emerge with aluminum wiring installations. Homeowners and electricians reported issues such as flickering lights, warm-to-the-touch outlets,  burned wiring, arcing at receptacles or switches, and even electrical fires. Upon investigation, it was discovered that aluminum wiring had several properties that made it less suitable for residential use:

1. Oxidation: Aluminum oxidizes rapidly when exposed to air. The oxide layer that forms is not conductive, leading to increased resistance at connections.
2. Thermal Expansion: Aluminum expands and contracts more than copper when subjected to temperature changes. This expansion and contraction can loosen connections over time, causing arcing and overheating.
3. Galvanic Corrosion: When aluminum wiring is connected to devices designed for copper, a chemical reaction called galvanic corrosion can occur. This weakens the connection and increases resistance.
4. Brittleness: Aluminum is more prone to damage from bending and twisting compared to copper. This brittleness can result in broken wires and compromised connections.

Adding to these problems there was confusion among homeowners and professionals who were unfamiliar with the “new technology” requirements would replace or repair parts with incompatible options.

Response and Regulations

As the issues became more apparent, organizations such as the U.S. Consumer Product Safety Commission (CPSC) and the National Electrical Code (NEC) began to investigate and respond. By the mid-1970s, the NEC introduced new standards requiring the use of aluminum wiring only with devices specifically rated for aluminum, often marked as “CO/ALR” (copper-aluminum revised).

Additionally, techniques such as using anti-oxidant compounds and special connectors were developed to mitigate the risks associated with aluminum wiring. Despite these measures, the reputation of aluminum wiring was severely tarnished, and its use in residential construction dwindled.

Modern Considerations and Safety Measures

Today, solid single strand aluminum wiring is still present in many older homes, and it poses a potential safety hazard if not properly maintained or updated. Homeowners with solid strand aluminum wiring should be vigilant and consider the following safety measures:

1. Inspection: Have a qualified electrician inspect the wiring for signs of deterioration, improper connections, and other issues.
2. Corrective Measures: Utilize approved connectors, such as the Copalum connector, to ensure safe connections between aluminum wiring and devices.
3. Replacement: In some cases, replacing aluminum wiring with copper may be the best option, especially in areas with high electrical loads or frequent issues.

Conclusion

The history of solid core aluminum electrical wiring is a testament to the complex interplay between innovation, cost, and safety in the construction industry. While it provided a cost-effective solution during a time of economic pressure, the unforeseen dangers and subsequent failures underscored the importance of rigorous testing and regulation. Homeowners and electricians must remain aware of the potential hazards and take appropriate measures to ensure the continued safety and reliability of electrical systems.

Most home inspectors don’t remove the dead front cover to look inside the electrical service panel. But SacPro home inspectors do remove the cover if it is safe to do so. Our highly trained SacPro home inspectors know what to look for at the home inspection and takes the time to look where other inspectors won’t.

We look for more. We find more. We take the time to do each home inspection right.

Ground Fault Circuit Interrupters (GFCIs): Understanding and Installation

In the United States nearly 300 electrocutions occur annually.  Ground Fault Circuit Interrupters (GFCIs) are essential safety devices designed to protect against electrical shocks. GFCI required in areas where water and electricity may come into contact.  The installation and proper maintenance of GFCIs are important safety issues.

What is a GFCI?

GFCI come in different and are designed to prevent electric shock and potential electrocution. A GFCI is a fast-acting circuit breaker designed to shut off electrical power in the event of a ground fault. Ground faults occur when the electrical current finds an unintended path to the ground, such as through water or a person.  A properly functioning GFCI does this by detecting an imbalance caused by electrical leakage between the normally energized conductor (“hot” wire), and the common (“neutral”) return conductor.

Why are GFCIs Important in California?

In California, GFCIs play a crucial role in ensuring the safety of residential, commercial, and industrial electrical systems. Due to the state’s diverse climate and widespread use of electricity, there is a higher risk of electrical accidents. Electrical accidents are more prevalent in areas prone to moisture, such as bathrooms, kitchens, outdoor spaces, and pool areas. By installing GFCIs in these locations, homeowners and businesses can significantly reduce the risk of electrical accidents and comply with California’s electrical safety requirements.

Requirements for GFCI Installation in California

California’s electrical code is based upon the National Electrical Code (NEC). NEC mandates the installation of GFCIs in specific locations within residential and commercial buildings. These locations typically include:

1. Bathrooms
2. Kitchens
3. Laundry rooms
4. Garages
5. Outdoor outlets (including BBQ islands and rooftop outlets)
6. Pool and spa areas
7. Electric Vehicle (EV) charging equipment

All new construction or renovation projects in California must adhere to the state’s GFCI requirements, ensuring that these safety devices are installed in accordance with the latest electrical codes and standards.

Installation and Maintenance

By using a digital circuit analyzer SacPro home inspectors have found approximately 50% of all pre-2008 GFCI fail to function within manufacturers’ specifications.  All pre-2008 GFCI should be replaced with new GFCI equipment. This recommendation is not only because of the high failure rate, but also because the equipment is more than 10 years old and past its expected service life.

Installing GFCIs requires careful attention to detail and knowledge of electrical systems. In California, it is recommended to hire a licensed electrician who is familiar with local electrical codes and regulations to ensure proper installation and compliance.

Regular maintenance of GFCIs is also essential to ensure their continued effectiveness.  Dirty fingers, airborne oils and dust can gum up buttons and prevent GFCI outlets from properly functioning.  Testing GFCIs at least once a month is recommended to verify that they are functioning correctly. Additionally, GFCIs wear out and should be replaced every 10 years to ensure optimal safety.

Finally, it is easy to improperly wire a GFCI.  Many modern GFCI are equipped with a LED light.  An improperly wired GFCI may still have an illuminated LED, but still not properly supply power through the outlet.  Care and attention must be given to properly wiring the “Load” and “Line” terminals of the GFCI, and GFCI equipped outlets should only be installed by a qualified and licensed electrical contractor.

How do I know if my GFCI is properly functioning?

Only a circuit analyzer can determine the functionality of a GFCI protected outlet. The plug-in “puck” testers fail to determine current, resistance, speed of functionality, and the presence of a false ground. A circuit analyzer properly identifies the speed of the circuit interruption and measures the Amperage during the interruption. A circuit analyzer also measures voltage drop and if any false grounds (bootleg grounds) are present. Each SacPro home inspector carries a circuit analyzer with them during a home inspection.

Conclusion

In California, where electrical safety is paramount, the installation and maintenance of GFCIs are crucial for protecting against electrical shocks and ensuring compliance with state regulations. By understanding the importance of GFCIs and following proper installation and maintenance procedures, homeowners and businesses can create safer environments for themselves and others.

Here we will focus upon using ultraviolet light (UV) to in dealing with pathogens (viruses, bacteria, micro-organisms) as a possible home upgrade.

What little bugs are swirling about and growing in the air you breathe? Most of us spend a lot amount of time in our homes sleeping, bathing, eating, and recreating, the so quality of our air matters.

This is where proper air filtration and even air sanitation (like ultraviolet lighting in HVAC ducting) may be and option for you.

But does UV lighting actually work? What kind of UV light should you get? There are single bulb, double bulb, even 4 bulb models, with 30 watt, 36 watt, and 72 watt versions. Some are 24 volt DC, while others are 120 volts AC. There are also DIY versions.

It seems every HVAC company is pushing to sell you on their UV system. These companies all tell you to buy their system if you can afford it.

But our review of their systems leaves us questioning their claims, and the quality and effectiveness of many of their products.

First, what is an ultraviolet lighting system? And how does it connect to your HVAC system? What is needed for it to work reliably?

Ultraviolet light occurs naturally within the spectrum of sunlight, except we cannot see it with our naked eye. UV “radiation” is known to age our skin, cause skin cancer, cause cataracts, yellow the whites of our eyeballs, break down plastics, and fade pigments and dyes.

Fortunately, UV also kills viruses and bacteria if it is the right wavelength and the exposure time is long enough.

Scientists have known for decades that broad-spectrum germicidal UV light, which has varying wavelengths between 200 and 400 nanometers (nm), is highly effective at killing many bacteria and viruses by destroying the molecular bonds that hold their DNA together. This conventional UV light is routinely used to decontaminate surgical equipment, but is harmful to human tissue.

Explaining the Ultraviolet Spectrum
UV-C 100-280 nm (nanometers, or 0.000000001 meters long)
UV-B 280 – 320 nm
UV-A 320-400 nm
Useful Range: 200 – 320 nm disinfects air and surfaces, to varying degrees and safety. Example: 260 to 265 nm is ideal for killing E. coli.
Useless Range: 320 – 400 nm (blacklights and sun tan lamps) is ineffective.

The household UV light units for HVAC systems are most typically installed by cutting a hole through the sheet metal wall of the heat exchange coils of the HVAC system. This type of installation, if there is a good seal, makes sure you are not exposed to the light.

But what UV wavelength are the best one for killing novel corona viruses (MRSA, H1N1, H5N1, and others), as well as (stinky) bacteria?

According to Columbia University Irving Medical Center, 222 nm (far wave) wavelength is ideal for killing MRSA, H1N1, H5N1, and other influenza (“flu”) viruses, without the negative human tissue consequences of broad spectrum UV lights. Because these are safe for human tissue, they are now being installed in hospital overhead lighting systems.

But does 222 nm matter inside of an enclosed HVAC system where the light is hidden and air is rushing by? No. Most commercially available UV light systems are 253.7 (254) nm units at either 30 watt, 36 watt, or 72 watt bulb varieties.

The wattage of the bulbs matters because the amount of Energy required to kill the pathogens = amount of Power x Time [ E_(J) = P_(W)× t_(s) ]
So the higher the wattage, the less time will be required to kill the virus.

How much time is needed for UV light to kill viruses?
The research says at least 5 seconds for antibiotic resistant viruses, and often time as much as 2 minutes (Staphylococcus aureus and Enterococcus faecalis) Humidity also matters. The lower the humidity the better.

But when your HVAC system is circulating air, none of that air will be in front of any UV light system for even 5 seconds. So now what?

Here is what the United States Environmental Protection Agency (EPA) has to say about using ultraviolet lighting in HVAC systems:
“[T]ypical UVGI cleaners used in homes have limited effectiveness in killing bacteria and molds. Effective destruction of some viruses and most mold and bacterial spores usually requires much higher UV exposure than is provided in a typical home unit.” [Emphasis Added]

U.S. National Library of Medicine, National Institute for Health does have a write-up about a limited experiment with a very small control group. That study (of a 4 floor building) showed a measurable reduction in mold.

Always ask for written proof about viruses from these heating and cooling companies. These HVAC companies are claiming these products work for killing viruses and bacteria. In the laboratory UV lights do kill pathogens when the air is still. But what about fast moving air through a HVAC system?

Ask for independent verification based upon a published study before you spend hundreds of dollars (or in some cases thousands), to get a UV system installed in your HVAC system.

Your home is probably the largest investment you have. With that in mind, there are three things to justify when considering any home upgrade:
1) Cost – UV system cost $120 – $700 parts, plus the cost of labor for installation costs, plus ongoing bulb replacement costs each year.
2) Performance / Quality – Not known to work in a HVAC system application. Still awaiting evidence…
3) Return on investment (ROI) – None if it doesn’t work as promised.

Final Verdict? Fail
(Until we see evidence to support that it works in HVAC systems)