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Zinsco Electrical Panel Hazards
Zinsco Circuit Breaker Information

This Zinsco electrical panel article 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.

We include advice on how to identify Zinsco, Sylvania Zinsco, and Kearney electrical panels and circuit breakers, and repair or replacement advice for those products.

In this article series we discuss: the hazards of Zinsco or Zinsco-Sylvania electric panels; Zinsco & Zinsco/Sylvania electrical panel identification guides & Kearney electrical panel identification guide. Independent testing of Zinsco breakers confirms failures.

Zinsco failure reports, though few in number, indicate severe failures of Zinsco electrical panels / circuit breakers including failure of the circuit breaker to trip on overcurrent, arcing and burn-ups at the breaker to panel bus bar connection, and circuit breaker burn-ups.

Zinsco & Zinsco-Sylvania Panel Replacement Recommended, Zinsco Sylvania Panel Breaker-to-Bus Connection Arcing. How should Zinsco panels be repaired: electrical panel replacement alternatives, What are the typical costs to replace a Zinsco or Zinsco-Sylvania Electrical Panel?

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Zinsco Electrical Panel Advice for Homeowners and Home Buyers

Zinsco breaker burnup (C) J P Simmons & D J FriedmanZinsco and Zinsco-Sylvania circuit breakers of the design described here do not offer the level of overcurrent and fire protection provided by most other electrical panels and circuit breakers.

Watch out: OPINION: we do not recommend installing "replacement" Zinsco circuit breakers as there some indications that the performance and safety of those devices may be poor.

Article Contents

Zinsco Electrical Panel & Breaker Test Results

Limited test results reported by Dr. Jess Aronstein (who is cited further at REFERENCES) indicate that the central Zinsco electrical panel and circuit breaker failure problem appears to be burn ups at the clip-to-bus connections such as shown in our photo of a burned Zinsco electrical panel bus and breaker.

A circuit breaker whose bus connection burns can lead to overheating damage to the circuit breaker itself, rendering it non-functional.

For a summary of Zinsco and UBI-Zinsco-Replacement circuit breaker test results to date,

see ZINSCO CIRCUIT BREAKER TEST REPORT - separate article.

Also see ZINSCO FAILURE REPORTS where we indicate that nearly 32% of the Zinsco circuit breakers tested to date failed to trip as required by the UL testing standard. A very small sample of UBI-brand replacement circuit breakers for Zinsco panels also failed to trip.

Photo at page top of a burned and failed Zinsco main circuit breaker, courtesy of J. P. Simmons - Mr. Electric. Simmons adds: "In this case the failure damaged the main wire to a mobile home also (you can see the melted wire to the left of the main). This is a good example of why I do not like to see anyone remove these breakers. You can not tell how bad they are damaged by looking at them.

Zinsco Panel Field Failure Reports

With the exception of the more seriously failing FPE Stab-Lok electrical panels, we have not received a similar number of field failure reports concerning other electrical panel brands that also use aluminum parts and that are or were priced in the same range as Zinsco.

This means homes with this equipment may be at greater risk of fire or other electrical hazard.

Zinsco & Zinsco-Sylvania Panel Replacement Recommended?

Zinsco no-trip (C) InspectApediaWhere Zinsco electrical panels and Zinsco circuit breakers are in use, arcing, contact-point burn, and even circuit breaker case blow-out have been observed in the field.

We do not have statistically solid data that supports an unequivocal argument to replace Zinsco electrical panels.

However, based on field reports to-date and preliminary tests, where Zinsco and Zinsco-Sylvania electrical panels are discovered in buildings a homeowner should consider replacing the panel to reduce fire and shock hazards and owners should be careful to avoid overloading their electrical circuits where this equipment is installed.

Building owners or electricians encountering problems with this equipment are asked to contact us to add that information to our electrical failure data base in an effort to develop accurate safety information which is then shared with appropriate federal and state agencies.

Thanks to Mr. James Simmons, a licensed electrician with extensive field experience and the contributor of most of the photos and case reports at this web page.

Our photo (above left) illustrates a burned-up electrical receptacle whose circuit was protected by a Zinsco circuit breaker that failed to trip and in fact had burned itself in the panel.

Zinsco Sylvania Panel Breaker-to-Bus Connection Arcing

A principal Zinsco™ circuit breaker (or Sylvania™ or GTE-Sylvania™ or Kearney™ electrical panel using this circuit breaker) point of failure appears to be at the point of contact where the circuit breaker contacts clip onto the electrical panel bus, combined with the use of an aluminum electrical panel bus.

As described at

ZINSCO FAILURE REPORT PROCEDURE, expert testing on this equipment has shown that circuit breakers do not trip about 25% of the time when exposed to overcurrent - risking overheating, fire and other hazards. The failure rate of competitive-brand circuit breakers is much less than 1%.

In addition to advice on identifying Zinsco™ panels, inspecting Zinsco electrical panels, and repair/replacement advice, we provide field photographs of circuit breaker failures: overheating, burnups, failures to trip, overcurrent protection failure. This document includes field reports of failures and additional anecdotal evidence.

See ZINSCO FAILURE PHOTOGRAPHS and ZINSCO FAILURE REPORTS.

Zinsco Panel Repairs

Repair advice (replace the equipment) is provided at

ZINSCO REPLACEMENT PANELS and

at REPAIR ELECTRICIANS we list electricians who have informed us that they have specific experience with this equipment. Lots of other licensed electricians are also qualified to replace electrical panels; it's best if your electrician is one who is familiar with this issue.

Replacement Zinsco circuit breakers and replacement copper-plated bus bars for Zinsco / Zinsco-Sylvania electrical panels are advertised. Without evidence of a design change in the product or support from independent expert testing, the effectiveness of these replacements is not clear.

As a not-for-profit activity, we have been collecting information and field failure reports for Zinsco/Sylvania electrical components since 1996 in an effort to develop credible failure-rate information which is then shared with the U.S. CPSC and with other electrical failure researchers and educators.

Zinsco History, Age, Dates & Patents for Zinsco Electrical Panels & GTE-Sylvania Zinsco Electrical Panels

This section has moved to ZINSCO ELECTRICAL PANEL HISTORY & AGE

See also ELECTRICAL PANEL AGE

Photos of Frank Adam Split Bus Electrical Panel & ID Label

Moved to FRANK ADAM ELECTRICAL PANELS

 




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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2022-11-15 by InspectApedia (Editor)

@Bruce Russell,

Actual cost of the electrical panel itself maybe a few hundred dollars on the installed cost may be 1200. Those prices vary of course and don't consider site conditions that might increase the cost of the job.

Please see our ELECTIONS DIRECTORY here

Or a simple Google search for "electrician santa rosa ca" showed this map with a list of area electricians. Give them a call for an estimate.


On 2022-11-15 by Bruce Russell

I am looking for an electrician near Santa Rosa, CA who can replace two Zynsco panels I have in a 400 amp system. The estimate I got from one electrician was astronomical.

What's an average price for the replacement and labor in Northern CA about 70 miles north of San Francisco? And can you supply contact info for someone near Santa Rosa, CA?

On 2022-09-13 by InspectApedia-911 (mod) - Zinsco panel should be replaced

@Kevin,

I can't pinpoint the bus rating of that Zinsco panel from the photo - probably in the 100A range - but

Watch out: instead of working on the panel and its contents, the panel should be replaced as we explain in this article series.

If you're an electrician, and if your experience is anything like mine, the last person in the building who touched the electrical system will be blamed if / when later there's an electrical fire or injury.

On 2022-09-13 by Kevin

Trying to find the bus rating on this panel, label was faded over the years.

100A Zinsco panel (C) InspectApedia.com Keving ... 100A Zinsco panel (C) InspectApedia.com Keving

On 2022-08-26 by InspectApedia-911 (mod) - What is the life expectancy of a Frank Adams panel?

@kristeen lentvorski,

If you have a building with a Frank Adams electrical panel most inspectors would tell you it's long obsolete.

Details are at FRANK ADAM ELECTRICAL PANELS

Excerpting from that page you'll read:

Frank Adam electrical panels ... do not offer the level of overcurrent and fire protection provided by most other electrical panels and circuit breakers.

Independent test results show that Frank Adam circuit breakers had a significantly higher failure rate than most other electrical panel brands.

On 2022-08-26 by kristeen lentvorski

What is the life expectancy of a Frank Adams panel?

On 2022-02-22 by Inspectapedia Com Moderator

@mg,

Please take a look at the article above and if you are more curious, at the additional articles documenting the fire hazard, failure mechanism, and innate design hazards of Zinsco breakers and panels.

You should not replace a breaker, you should replace the Zinsco electrical panel.

On 2022-02-22 by mg

Have an early Zinsco panel with a copper bus. Replacing a breaker. Is it advisable to use a copper contact clip in the replacement breaker? Many thanks !

On 2021-09-21 by inspectapedia.com.moderator - HOA Board needs to replace Zinsco equipment

@HOA Board Guy,

Unfortunately we've indeed had field reports of Zinsco mains/meter burnups too;

Ask your electrician to look at the main breakers and their bus connection. If that confirms the distinctive Zinsco design, you do want to replace those components.

Your contractor might propose an inspection program to identify and replace the worst equipment first: where there are already signs of overheating, burns, or corrosion;

On 2021-09-20 by HOA Board Guy

My condo associations' insurance carrier just flagged our building's Zinsco equipment and wants us to replace everything in 60 days to keep coverage active. We have no problem replacing the regular Zinsco "load center" electrical panels inside the building.

However, the meter mains, main breakers, and shutoffs look to be a lot more involved/expensive, and I'm questioning if these are posing the same level of risk/danger as the interior panels, especially if they reside outside the building or in the garage. Thoughts?

Unfortunately we don't have unlimited funds to replace our entire electrical infrastructure all at once, so I'm trying to balance safety and fiscal responsibility. It might mean changing carriers to one that'll let us do this over time.

On 2021-09-10 by mak.church (mod) - There is not and was not a Zinsco panel recall

@GP,
There is not and was not a Zinsco panel recall. You should replace the electrical panel.

See more information here:

ZINSCO ELECTRICAL PANEL - WARRANTY AND CONTACT INFORMATION

On 2021-09-09 by GP

Are there any recalls for any of Zinsco's products? I'm wondering if we have any recourse for such a faulty, dangerous panel!

On 2021-09-04 by inspectapedia.com.moderator - Zinsco-Sylvania electric panel failure report

@Nancy Pellone,

Thank you for an important and helpful Zinsco-Sylvania electric panel failure report.

I agree that all of those panels are unsafe and should be replaced.

Too often people are misled by not having already observed a sign of trouble, but it's quite evident that although corrosion and overheating at the breaker-bus connection can happen over a long period, the actual manifestation of trouble can be sudden and severe. IMO these are not sleeping dogs to let lie.

If you can post more details and photos of the equipment/damage (one photo per comment) that would be most helpful.

On 2021-09-04 by Nancy Pellone

report: April 25,2021 Incident for Zinsco outside meter bank equipment and Sylvania/Federal Pacific. The main meter switch exploded and all points in this online information concerns me living in a Condo Association of 60 units. The Board here with our HOA has collected estimates to replace the outside meter equipment.

We are in 1 of the 4 buildings here urging the Board to move more quickly on this. Duke Energy and local Electrical Company-Live Wire highly advised to replace the inside Zinsco electrical panels. We are in Largo, FL. The buildings were constructed in 1972.

We need to avoid any future electrical issues. The Board and property mgt company are meeting soon to determine the Company and then move this forward.

I recommend more awareness at the purchase side of seller's be advertised to replace faulty Zinsco inside panels, prior----to the closing of units. Individuals need to be better informed of the seriousness of these poor products. Potential fires is NOT anything to postpone taking care of!!

On 2021-03-03 - by (mod) -

GTE Sylvania Zinsco Electric Meter Base
@Cole D Bene,

IDENTIFY ZINSCO SYLVANIA METER BASE

Identifies the meter base in your photo, why don't you show them that and perhaps give a printed copy of the Zinsco safety warning articles given here.

On 2021-03-03 by Cole D Bene

I am trying to convince PGE in CA that I have a Zinsco 200 amp meter main. The panel has 2 100 amp breakers installed for 2 subpanels. All of the paperwork has worn away. Exactly like the photo. please contact me if you can help.

Thankyou, Cole Bene

On 2020-08-22 - by (mod) -

Ethan

There was never an actual mandatory recall of Zinsco Sylvania electrical panels but they are, nevertheless, unsafe and should be replaced.

Your photo shows Zinsco-type circuit breakers. Yes, it's in that group of unsafe circuit breakers.

On 2020-08-21 by Ethan

Sylvania Box is this one on the recall list?

Unsafe Zinsco Sylvania electrical panel and circuit breakers (C) InspectApedia.com Ethan

On 2020-02-08 - by (mod) -

Several panel or circuit or device problems might increase your electrical bill, such as a failing motor or a current leak. Ask your electrician to check the current draw on each circuit. Let me know what you find.

On 2020-02-08 by Mike

Zinsco 100 amp panel can it cause a high electric bill with no apparent visual problem like three times the area average

On 2019-10-19 - by (mod) -

You are correct that Zinsco panels should be replaced, and that they are not repairable.

However I don't think you saw here an article about Zinsco with the wording you report since that wording is incomplete and mistaken in several regards.

On 2019-10-18 by Edward Juarez

Good afternoon

In the past the site had great reference sheet or hand out pamphlet which basically said in 9 item not to service Zinsco, do not change parts replace panel, also said NEC has pulled its overrating current protection for panel breakers I can not find this page anymore what happened

On 2019-04-29 - by (mod) -

I'm not sure I understand the question but it would be normal to have two 120-volt legs entering a residential electric meter.

Be careful if you're not trained in safe electrical testing practices you could be shocked or killed.

On 2019-04-29 by james cooley

meter saidigot120v

Question: Identify this Electrical Panel: Frank Adam Electric Co. Brand

Can you identify the panel brand shown in the attachment? - JW by private email 2019/06/12

Frank Adam Electric Co. Panel, (C) John Weber Hartford HSB cited at InspectApedia.com

Moderator reply:

See IDENTIFY FRANK ADAM ELECTRICAL PANELS

...

Continue reading  at GTE-SYLVANIA-ZINSCO FAILURE MECHANISM or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see ZINSCO SYLVANIA ELECTRICAL PANEL FAQs - questions and answers about Zinsco Sylvania electrical panels posted originally at this page.

Or see these

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ZINSCO SYLVANIA ELECTRICAL PANELS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


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