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ZINSCO SYLVANIA ELECTRICAL PANELS
This article series discusses the electrical, fire, and shock hazards associated with Zinsco electrical components, circuit breakers, electrical panels, including certain Sylvania electrical panels and breakers which are in fact of the same product design and origin. Page top photo of a Zinsco electrical panel provided by Washington state electrician J. P. Simmons
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How and Where to Report Zinsco or Sylvania Electrical Equipment Failures to the U.S. Consumer Product Safety Commission
Dangerous Product Reports to the US CPSC: To report a dangerous product or a product-related injury, call CPSC's hotline at (800) 638-2772 or CPSC's teletypewriter at (800) 638-8270, or visit CPSC's web site at SaferProducts.gov.
You can use this CPSC web page to report Zinsco or Sylvania-Zinsco equipment failures and problems.
Please also report incidents to the InspectAPedia. com Editor.
How and Where to Report Zinsco or Sylvania Electrical Equipment Failures to the Website Author for Compilation
Submissions of field failure reports and failure photographs wanted. Contactthe web author
Visual Inspection of Zinsco Panels Will Not Reliably Show Unsafe Conditions
Most of the time we check a Zinsco/Sylvania panel it looks great to the naked eye even with the cover off. There may be no obvious heat damage or signs of conductor damage. Home inspectors who comply with the ASHI or other Standards of Practice will remove the electric panel cover but they will not remove the circuit breakers themselves nor perform any other disassembly of electrical panel components. This restriction is established for the safety of the inspector who will not usually have the same level of electrical training as a licensed electrician.
Inspecting in this manner will usually not disclose damage even though very significant damage such as overheated connections, blown-out circuit breakers, or other failures may be present. Many of the panels we see do not have a main breaker so the only way to disconnect all the power is to have the meter pulled out by the power company - a step well beyond the scope of a home inspection.
Inspection of Zinsco Electrical Panels Might Actually Increase the Risk of a Future Failure
Many times when a licensed electrician pulls out the breakers, the breakers and bussing are damaged. I [J. Simmons] have personally seen them in such poor condition that the part of the breaker that pushes onto the bussing has become welded to the buss. The breaker actually broke apart with the connection staying on the buss and the rest of the breaker coming out) when I tried to remove it.
How Often do Experts find Damaged Zinsco Electrical Equipment
We see damage in about 25% of the Zinsco/Sylvania panels that are checked. The problem occurs mostly on circuit breakers feeding circuits that have a steady heavy load on them (like heaters, hot water tank, dryer), and on circuits that are often overloaded such as circuits that supply the kitchen or bathroom.
In houses with Zinsco/Sylvania electrical panels and circuit breakers, I [Simmons] have tested these circuits with up to 30 amps on a 20 amp circuit breaker. The Zinsco circuit breaker will carry the overload for a long time without tripping. This causes the connection to heat up and start arcing to the buss bar. The problem is primarily in the panels with aluminum buss bars, but also has been seen in the ones with copper buss. Moisture seems to accelerate the process.
Recommended Home Inspection Report Warning Language for Zinsco Electrical Panels & Circuit Breakers
These circuit breakers are very poor quality and do not provide a safe level of over current or short circuit protection. In our opinion [J. Simmons and D. Friedman], home inspectors who observe Zinsco or Sylvania-Zinsco electrical equipment in a home should warn the homeowner that
A Zinsco TM or GTE-Sylvania™ -Zinsco™ [or Kearney™] electrical panel is installed in this building. Serious electrical hazards may be present in the electrical panel which could result in overheating, fire, or inability to turn off the electrical power in the home. A licensed electrician who is familiar with this equipment should be called to inspect the panel for immediate fire and shock hazards.
While replacement of this equipment is not currently required by law, regardless of its visually-apparent condition, we recommend that homeowners replace this equipment. Significant expense may be involved.
With the exception of the more extensively-studied FPE Stab-Lok electrical panels, we have not received a significant number of field failure reports concerning any other electrical panel brands that also use aluminum parts and that are or were priced in the same range as this Zinsco equipment. This means homes with this equipment are at greater risk of fire or other electrical hazard.
Additional information about this hazards is available at an independent building failures research website: http://InspectAPedia.com/electric/Zinsco.htm
More in-depth, un-biased, expert information on these topics and on building defect inspection, diagnosis, & repair can be found at More Information below.
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