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What is a Zinsco Electric Panel?

Zinsco electric panels were installed in tens of thousands of homes across the United States – mostly in the 1960s and 70s. The company eventually went out of business, but many of the panels that had already been manufactured were still installed.

These panels have some inherent problems that can make them unsafe. They have been blamed for both house fires and electrocutions.

Besides Zinsco, these panels are also known/labeled as Sylvania, GTE and Kearney electric panels.

Zinsco Electrical panel

What is the Problem with Zinsco Electrical Panels?

The two main issues with Zinsco panels are the risk of fire and electrocution. I’ll explain both of these below.

Zinsco Electrical panels have an aluminum bus bar. A bus bar is the part of the panel that the individual breakers attach to when the breakers are installed in the panel.  (see photo below)

Zinsco Panel busbar
It is the bus bar that carries the electricity and transfers it to the breakers. From the breakers, the electricity goes to the wires and then to the individual components in the home.

Aluminum is very prone to corrosion, and corrosion increases electrical resistance which causes more heat to be generated as electrical current flows. (The bus bars shown in the photo above do not show signs of corrosion and are in relatively good condition.)

Once corrosion starts to form on the busbar, heat will be generated, and then corrosion and heat will continue to increase over the course of time.

Eventually, the connection of the breaker to the bus bar can get hot enough that the breaker essentially melts onto the bus bar. At this point, it is very likely that the breaker will no longer trip when a breaker normally would trip.

Electrical breakers are designed to trip and shut off the flow of electricity to a circuit in the event of an overloaded circuit. (An overloaded circuit means that too much current is flowing.) If too much current flows through a wire, then the wire will heat up, and a fire can result.

A tripping breaker helps keep a home safe by shutting off the flow of electrical current if a circuit is overloaded. Therefore, it is essential that breakers be able to trip when a circuit is overloaded.

Some studies have shown that as many as 20% to 30% of Zinsco breakers failed to trip when exposed to an over-current event.

Some studies show that 20%-30% of Zinsco breakers failed to trip in an over-current event.

Another problem with these breakers is that occasionally, when the breaker is tripped or manually flipped to the OFF position, the breaker may not actually be off and will continue to send electricity out to the wire connected to it.

This can be an electrocution hazard if someone shuts off the breaker to do some maintenance and then touches a live wire thinking the circuit is dead.

Also, if a breaker trips due to over current, but is still letting electrical current flow out to the circuit, it can result in a fire as this high current continues to flow, causing the wire and breaker to heat up.

How to Know if You Have A Zinsco Breaker Panel in Your Home

It is fairly easy to identify a Zinsco panel due to its unique color scheme.

You should see the common colorful breakers (they are often red and green). Below are some photos to aid in determining if you have a Zinsco panel in your home.

These panels are also typically labeled with the words Zinsco, Sylvania, GTE, Kearney, or a combination of these words.

zinsco breaker panel
zinsco breaker panel
zinsco electrical panel
zinsco breaker panel
zinsco breaker panel

What Should You Do if You Have a Zinsco Breaker Panel?

A Zinsco Electrical Panel in your home will increase your risk to a degree, and your home will certainly be safer without one.

My recommendation to you would be to have the panel replaced by a licensed electrician as soon as possible. 

While I see ten to twenty of these panels in homes every year (and the home is still standing – it has not burned down) it just is not worth the risk to have one in your home.

If you don’t have the money (probably about $2500 – $3500) to replace the panel now, you should at least hire an electrician to inspect it by pulling the breakers and inspecting the bus bar and other components in the panel.

The results of this inspection will tell you just how urgent it is that you replace the panel. You may be able to wait a while longer, or you may need to replace it immediately. The licensed electrician that you hire should be able to tell you just how urgent it is.

I hope that this information is helpful to you and helps you in your decision making about the Zinsco panel in your home.

If you have any questions about Zinsco Electrical Panels or home inspections in general, please feel free to contact us.

© 2023 Mike Morgan

This article was written by Mike Morgan, the owner of Morgan Inspection Services. Morgan Inspection Services has been providing home, septic and well inspection services throughout the Central Texas area since 2002. He can be reached at 325-998-4663 or at mike@morganinspectionservices.com. No article, or portion thereof, may be reproduced or copied without prior written consent of Mike Morgan.


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