Fire Sale

To the electrical aficionados on the forum - should a circuit breaker supplying power to the 120v outlet trip if something like a short on the EBH wiring happens? Or would installing a GFCI outlet on that circuit be a wise move since they are more sensitive to short situations?

 

If there is a short yes. But you still get 13-15A out of it generally before it trips. You are attaching a heating element to an untended metal assembly surrounded by plastic sitting in your garage. This is no different then plugging a space heater in and going to sleep. It sometimes ends badly. The short will only happen after the wires have become so hot the insulation melts off and then shorts the wires together. But by that time, you probably already have a problem.

And something most people overlook are old circuit breakers in their main panel. If your house is a couple decades old, it is probably time to replace all the breakers. They aren't meant to be tripped over and over, and even time is an enemy. You may have a 15A breaker on the line, but it takes 20A or more for it to trip because it is too old. For a few bucks a piece, it is not worth skimping.

 

Well, my house was built in 1941 but I have a seperate panel in my garage (Really its a 3/4 garage, 1/4 boat house because I live on a canal and the back part butts up with my seawall) that has VERY old circuit breakers in them. I am going to update the outlet that I plug my engine block heater, and the outlet that goes out to my boat. I'd rather be safe than sorry.

 

Ok, here is something interesting... I found the original plug with the suspected severed wire inside. True enough, one side sort of snapped upwards and had small burns on the ends, while the other side was unusually deformed. Could they have been that way from the factory originally?

At first, I started slicing lengthwise after the ribbed support. Since I found nothing there, I took off the rubber support and saw a small bulge obscured by the ribbed support near the body of the plug. When I sliced it open, I saw the cut and but relieved it didn't escalate into the adjacent wires to become a full blown short.






The other side

 

wow, impressive.

 

cya?

 

"A full blown short" is exactly the kind of failure you want. It is the easiest to detect, and exactly what the breakers in your electrical panel are made to detect. A full blown short would have sent a couple sparks, the breaker would have tripped and the entire circuit shut off. In the morning you would have woken up to a cold car with a blown breaker. Flip the breaker back to turn it on (as most people do without thinking why it was blown in the first place) and it would immediately trip again. Not until you unplug the offending appliance would the circuit come back to life. That is what you should wish for, not a quasi-failure that causes it to have thermal runaway.

 

..they say that lightning never strikes twice..

 

I built an addition to my house and I had to use special breakers for the extra bedrooms, I think they are called ARC/SINE breakers. they are suposed to be able to detect an arc due to a faulty space heater or other elec. device and prevent fires. It seems to me that may be a great investment for anyone using block heaters. they install right into your electrical panel so it would be almost no work to do it. you just need to see what brand of elecrical panel you have and get the proper size and put it in. I am not an electrician so I am not positive this would completly protect you, but I think they are made to prevent the same type of issue that likely started this fire.

Hope this helps

 

I went to google and searched to find Arc/sine breakers. Turns out they are really Arc-Fault Circuit Interrupter breakers. I got mine from Lows I don't remember them being very expensive, so I really encourage those who use block heaters to look into these. I think if you park your car in garage or carport attached to home you would be crazy not to
Arc-Fault Circuit Interrupter Installation in Rochester

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Arc Fault Circuit Interrupters (AFCI) monitor the sine wave of certain circuits and will trip under a working fault condition. Each electric circuit in Rochester has a sine wave, that cycles on a nominal frequency of 60 cycles per second. When it arcs it causes the sine wave to act unrecognizable unlike a normal sine wave.
When the AFCI detects an abnormal sine wave, it trips stopping what could be a working fault and potential fire hazard.
All new construction, specifically bedrooms, must have an AFCI circuit breaker installed. Call our experts to install one for you today and start protecting your family from dangerous electrical hazards that can occur in the home