How to Pass Electrical Safety Inspections in California

Zinsco Electrical Panels

by Gary | Jan 27, 2023 | Panel Upgrade

Zinsco Panels in Older Homes

Zinsco Electrical Panels, commonly installed in older homes up until the 1970s, have been known to cause fire hazards and may need to be replaced. If your home still has its original wiring, electrical panels, and appliances, you may need to replace these soon to prevent possible fire danger and other issues. Be especially cautious when dealing with older wiring. A panel upgrade may be needed if your home still has the original Zinsco panel. 

Are Zinsco Panels Safe?

According to the American Housing Survey conducted by the U.S. Census Bureau, more than half of all homes in the country were constructed before 1980 and would contain these panels if not replaced already. Zinsco panels often fail to function properly, putting homeowners and their homes at risk of electrical shock and fire.  As many as 25% of Zinsco circuit breakers could fail to trip in response to an overcurrent or short circuit, creating a potentially hazardous situation. 

Zinsco Box Breaker Box Problems

The electrical boards that have circuit breakers or fuses for all of your home's electrical circuits are referred to as circuit breaker panels. Circuit breaker panels are an essential home safety component. In the event of a power outage or overload, the breaker stops the flow of electricity. If a breaker can no longer trip in the event of an over-current or short circuit, an enormous quantity of power from the outside electrical supply surges into a home's panel and circuits. Once this occurs, it cannot be halted or turned off manually. Electricity will continue to burn until the fuel runs out or the wires melt. The panel could overheat and catch fire, endangering the home and its residents.

Zinsco Electrical Panel Fire Hazard

The old Zinsco panels are problematic due to the usage of aluminum bus bars. If a breaker melts to the panel's bus bar and can no longer appropriately trip in the event of an over-current or short circuit, an enormous quantity of power from the outside electrical supply surges into a home's electrical panel and circuits. Once this occurs, it cannot be halted or turned off manually. Electricity will continue to burn until the fuel runs out or the wires melt. The panel could overheat and catch fire, endangering the home and its residents.

The National Fire Protection Association (NFPA) publishes the National Electrical Code(r) (NEC (r) to give advice for residential and commercial electrical safety requirements in the United States. It is updated every three years to guarantee that people are safe from electrical shocks, fire hazards, and other electrical hazards. However, since aluminum is utilized in these older circuit breaker boxes, the safety requirements do not apply to the Zinsco panels. It cannot assist people who are currently in danger.

Are all Zinsco Panels bad?

According to tests, approximately one-third of Zinsco panels did not trip, according to InspectAPedia. This could be a risky situation given that circuit panel is crucial to regulate the flow of electricity into your home.  An older home's Zinsco panel might not be able to handle additional issues that will spring up as you begin upgrading your appliances. For example, the Zinsco panel would not be able to handle the power needed for a new air conditioning unit.  When you anticipate needing a lot of power, it's critical to check that your electrical system is current otherwise you may need a panel upgrade.

Zinsco Panel Recall

The issues with the Zinsco electric panel should have led to the recall of the Zinsco panels. However, the company did not recall the panels. Instead, the business was sold in 1973.  Then eventually the business shut down, so you can't get in touch with them to get your electrical panel upgraded.