What kind of circuit breaker is this?
June 10, 2014 12:22 PM

An electrician told me that I need to replace the main breaker on this board. He wasn't sure where to find them. I'm hoping someone here has an idea what kind this is so I can try to get it replaced. I live in Austin,TX, so either online or near here. Here's a picture
posted by jonclegg to Home & Garden (9 answers total) 2 users marked this as a favorite
Disclaimer: I am not an electrician.

It looks like a 220V main breaker for a Murray brand box. (I'm judging this is a Murray brand breaker box because of the different colored handles on your other breakers corresponding to different amperages.)

The two most common brands for circuit breaker boxes are Murray and Square D; the brands of breakers must match the brand of the box, as the breakers are not interchangeable. You can get either at any big box home improvement store.

It could be that your breaker box is neither of those brands, which would explain why your electrician didn't know where to get the breaker. (If it is Murray, then he should have known where to get it.)

Find out the brand of your breaker box; it should be on a label on the door in the panel you open (in your picture it looks like this door panel has been removed and set aside). If it's Murray, go to a big box home improvement store and ask for a Murray 220V 100 amp main breaker. If it's not Murray, use your favorite search engine to find an electrician's supply store in your area, go to them with the brand name, and ask for a 220V 100-amp main breaker.
posted by tckma at 12:38 PM on June 10, 2014


I'm not sure I get the question : that is, your electrician shouldn't have to think twice about this. It looks like you've got breakers that take up one slot but are themselves split, so one can double the number of circuits without having to replace the box/panel. This is not some strange voodoo. HomeDepot might not have it but any regular to-the-trades electrical shop would - and your electrician would be able to pick it up there.
So I guess I'm gonna suggest you get a second opinion.
posted by From Bklyn at 12:42 PM on June 10, 2014


I would second From Bklyn and also suggest you get another electrician: this seems like it should be basic, assumed knowledge for any licensed electrician. At the very least, if he were stumped, he could have removed the breaker, gone to his favorite supply house, and asked them to sell him a replacement.
posted by tckma at 12:48 PM on June 10, 2014


I had a similar issue at a friend's old house in Dallas. It might even be the same breaker type in the picture. We pulled out the broken breaker and took it to Home Depot. They didn't have it, but Lowe's did. It was about twice as expensive as a modern breaker.
posted by Uncle Jimmy at 12:50 PM on June 10, 2014


Your electrician shouldn't have to think twice about this.

It's essentially a sub-panel set up as a 200A main. I've not tried to source a 200A replacement breaker, but maybe your guy doesn't think he can find one since you not working with a "real" main panel.

I wouldn't hesitate getting a second opinion.
posted by humboldt32 at 1:32 PM on June 10, 2014


I am an electrician. Those are Zinsco breakers.

You should do a little research on the failure rates of Zinsco breakers. Trust me, if you research it, it will scare you. Zinsco is a terrible brand of breakers, with a very high failure rate.
You need to save money and when you can, replace that panel.

That said, you can find replacements - but they can be hard to find though. That brand is out of business (due to several big lawsuits over the failure rate of the breakers), and it is considered an obsolete brand. You can find them though - for example, on this website, Breaker King, which sells re-conditioned Zinsco breakers.

Also, as a side note, I would not judge that electrician too harshly. You are asking him to locate something that is obsolete and no longer in use. There is no reason why he should no where to get such a breaker, especially if he is young. Older electricians remember when these breakers were more common - the younger guys don't often see dinosaurs like that.

Also, to be clear - I am NOT advising you to purchase a re-conditioning Zinsco breaker. I giving you the link as a courtesy. My advice is to replace the panel. If you were a customer of my company, we would replace the panel, or I would walk away from the job - I would not get involved in trying to keep that panel limping along. But, if you want to have an obsolete dinosaur as your main source of electrical fire safety in your house, that is your business. Breaker King will sell you these breakers.
posted by Flood at 1:37 PM on June 10, 2014


Flood, how much should a new panel be?
posted by jonclegg at 2:30 PM on June 10, 2014


How much for a new panel? I wish I could just throw out a number, but it depends on where that is and what you want.

The cheapest side: they make retro-fit kits where you can take out all of the interior guts of the panel (breakers, busbar, lugs, ground bar) - and then install all new stuff. You do not even have to pull the wires out of the old box - you use the same old box. Just re-wire the thing's interior with an upgrade kit. Material and labor (in the Central Florida market), might be $500 or $700.

However, is that your main panel? You service size is 100Amps. Amps is the volume of flow (like if you think of a river of water, amps is the volume of water flowing, or volume of electricity flowing through the copper). When that Zinsco panel was put in, 100A was a lot. A lightning bolt is 200A.

Today, homes are built with 200A. Custom homes can be 400A. There are so many more electronics in the home today. Your AC could be 40Amps. The water heater could be 30Amps. The oven and cook top could be another 40Amps. That is 100Amps right there. I mean, the xbox is like 5Amps by itself, nevermind the TV, the modem, the cable box, and that halogen bulb lamp.

If you are going to invest in a new main panel - do it once, and do it right. It should last 20 or more years.

You could do the 100A retro-fit kit in the panel, but every year, the house is going to need more and more power.

If you are up-grading your service size, then a whole new host of questions appear. Where is the electric meter? Do you need a permit? (You probably do need a permit.) Many more questions.

Depending on lots of things about your house, a power up-grade and service change can range in price (in Central Florida) from $1000 to $3000. Huge difference in numbers, I know. But increasing your electrical service size is more than just the panel.
posted by Flood at 3:52 PM on June 10, 2014


If I were to replace a panel, I would at least price out the additional work to do the wiring for a generator. It might double the price (I really have no idea), but it would be cheaper and easier to have the electrician do both jobs at once. I don't have a generator, but we're about the last house on the street without one, so it's a resale consideration.
posted by SemiSalt at 4:15 PM on June 11, 2014


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