Watch those block heater cords!

So, I have a background with electrical gear. i've worked on high voltage switchgear, industrial manufacturing equipment, and the likes of many low voltage control systems. But, I apparently missed the boat when I decided to plug in the truck last night to keep it nice and warm for our record low temperature here on the california coast...

i've never once plugged the thing in since I've owned it, but with last night's temperature forcasted to get down to 26 at my house I figured "what the heck"

Ran the extension cord from the back of the house out to the carport, felt around under the bumper and grabbed the block heater cord, lined it up for a simple slide on into home, and KABANG! Like when the old man plugged in the tree on "A Christmas Story" A nice puff of ozone and plasma and the apartment went dark... Wife was going nuts, kid was screaming, my underpants were promptly filled. Turns out the cord had rubbed through on the radiator core support and was a dead short.

So, check those block heater cords BEFORE you plug the beast in for a winter nap, and keep a flashlight handy just in case...

haha! my cord just failed, rubbed on something underneath. no explosions though, just happened on one of the coldest days so far. super fun crawling under the truck at 20*f.

HA! Didn't blow up a cat in the process too, did you? Glad you made it out in one piece....with hair and eyebrows in tact.

Good thing you were home.... spare chonnies and all!

Funny thing is, I've been eyeballing my cord too. The only resistance is, I'm trying to see how cold I can make the truck start on its own. Only concern is oil temp at start-up.

So far so good, snaps off one to three rolls when cold. Frost this morning, but of course nothing like our minus F members.

Worst it ever got at the Casa is 19*F a few years ago. Worst since about 26-28F.

Time to check the cord! I don't have too many more chonnies.... I got coal for Christmas!

I plugged mine in a couple months back right before going to bed. I heard some weird popping noises outside, and looked out the window to see firelight coming from under the truck on the same side as the heater Unplugged it and ran out to check for damage; the plug had melted pretty good, and the pins in the heater fell right out when I pulled the cord.

Since then, I've been super paranoid with the new Napa block heater I installed, but also disappointed since it doesn't warm the truck nearly as well as the old one did...

Was the plug corroded/wet or did the wiring rub through somewhere?

120V AC will wake you up good, its that 12V DC that you should avoid

I dont understand how the block heater would blow the Main breaker

rhkcommander said:

Was the plug corroded/wet or did the wiring rub through somewhere?

120V AC will wake you up good, its that 12V DC that you should avoid

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I had the main battery cable chafe against the ball valve on my coolant filter setup. melted halfway through the cable AND melted half the handle on the ball valve.

the fuse in your garage is going to blow at 20 amps if the heater shorts. there is no fuse for the battery, and it has 1700 amps

Diesel_brad said:

I dont understand how the block heater would blow the Main breaker

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extension cord shorted from the heaters' plug. Or the heaters' wire is frayed or is internally shorted et cetera

gatorman21218 said:

I had the main battery cable chafe against the ball valve on my coolant filter setup. melted halfway through the cable AND melted half the handle on the ball valve.

the fuse in your garage is going to blow at 20 amps if the heater shorts. there is no fuse for the battery, and it has 1700 amps

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yep when you connect straight to the batt something has to give...

CaptTom said:

I'm trying to see how cold I can make the truck start on its own. Only concern is oil temp at start-up.

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I've got my truck to light off at -25*C (-13*F) to -30*C (-22*F) last week without too much trouble. As for the oil, I am running 15W40 in her, I just let her idle on high for 10 - 15 minutes before I apply my butt to the driver seat.

Oh, all this was NOT plugged in...because there isn't enough extention cord at the local hardware store to reach my truck from the house or garage.

rhkcommander said:

extension cord shorted from the heaters' plug. Or the heaters' wire is frayed or is internally shorted et cetera

.

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yeah, that would trip the breaker for THAT circuit, NOT the main. Unless the whole hose is on one breaker

I read somewhere that its best not to use an Xcord above 50ft long for the block heater, it is 1500 watts and draws 15 amps or so. The longer the Xcord the more amps are being drawn, and if you have 150ft of cord on a 20amp GFCI, or breaker, you are going to trip said breaker, or GFCI. This increasing amperage can be negated by using a higher gauge cord AFAIK

Goofyexponent said:

I've got my truck to light off at -25*C (-13*F) to -30*C (-22*F) last week without too much trouble. As for the oil, I am running 15W40 in her, I just let her idle on high for 10 - 15 minutes before I apply my butt to the driver seat.

Oh, all this was NOT plugged in...because there isn't enough extention cord at the local hardware store to reach my truck from the house or garage.

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That's pretty nice to know. I too run 15/40 and do warm up almost to the "T" you do. 'Sides, kids hate the cold iron inside if I don't when I take em to skewl.

One push of the throttle to set high idle, mine goes off about once the steam dissipates from the exhaust.... is it supposed too? I would think.

Our high today was 63F forcast for 65F tomorrow. We'll probably have frost again, clear skies and all.

At least there's one good thing about Klownifornia!

Diesel_brad said:

I dont understand how the block heater would blow the Main breaker

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My apartment has a 70 amp main breaker, and the wife had the electric stove going... Probably a weak breaker as well.

When my truck threw its belt, it ripped out the cord. I just have it tied away for now, haven't used a block heater all winter and she starts in 2-3 chugs every time.