Can I use a space heater with a low-gauge extension cord?

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obvs Social Distancing Grandmaster
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I have a space heater plugged into an outlet right by a window, but today I realized that on the other side of the room there is an unused outlet controlled by a light switch(the light switch next to the switch that controls the lighting in the room).

I would like the ability to turn the space heater off when I flip the light switch as I leave the room. But I know that this would require a longer cable, or an extension cord.

I was thinking of using a 12-gauge extension cord to plug it in.

Thoughts?
DukeofNuke FREE RADICAL
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Just move the heater.
even 12 ga will get hot. It's all about the amps.
juice Inadvertently correct
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Space heater plus extension cord is a formula ready-made for a fire.
ukimalefu want, but shouldn't, may anyway
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DukeofNuke posted:
Just move the heater.
even 12 ga will get hot. It's all about the amps.


I was curious, because I'm really not sure, but I thought 12 gauge was thick enough (but yeah, anything that heats will pull a lot of power)

So I googled it because I wanted to know, and I found this:

Choosing the Correct Extension Cord Sizes

Quote:
#12 16 Amps 1,920 Watts


Quote:
Warning
Special caution should be taken with electric space heaters. You should never use an extension cord to plug one of these heaters into a power source. Numerous house fires have occurred when heaters are plugged into extension cords, due to their high wattage and amperage demands. Instead, space heaters should be plugged directly into electrical outlets, but even there you must be careful not to exceed the amperage rating of that circuit. If you find that a circuit breaker trips or a fuse blows when you plug in a space heater, you should try another circuit with heavier wire and a larger circuit breaker amp rating.

dv
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12ga should be able to handle 16A, which is barely enough to run a most 1500W heaters in normal conditions. So you could do this for years and never notice a problem.

But if you're on a 20A breaker/fuse get something heavier just in case. (Otherwise the extension cord is the weakest link.) There are specific circumstances where a device like a space heater can draw power over spec without shutting off. (I don't know why, I've just seen it happen.) Let the breaker handle it.

The "never use an extension cord with high draw appliances" bit is generally good advice for folks who have a bunch of these sitting around and can't read the fine print (often printed directly on the cord itself.)

The amp rating of the light switch is also something to check. (The amp rating should be printed on it somewhere... some disassembly required.)

I would consider replacing you (probably) 1500w heater with a 800-1000w unit and getting a Kasa Smart Plug instead of an extension cord. Give yourself some headroom for other stuff on the circuit. FWIW, both our home offices are on the same circuit and we have pretty regular "laser printer vs. space heater" arguments in the winter. :lol:
obvs Social Distancing Grandmaster
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DukeofNuke posted:
Just move the heater.
even 12 ga will get hot. It's all about the amps.
You mean move the heater behind the bed?

I mean, I'm no expert, but I wouldn't think having an eight-inch-wide space heater in a one-foot-wide space between the wall and a bed where two down comforters and a wool afghan blanket hang off of the edge of a bed over several power cables would be ideal.

The current empty corner where the heater sits by itself with at least a foot of free space around each side seems like it might be a better choice.

:shrug:
obvs Social Distancing Grandmaster
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dv posted:
12ga should be able to handle 16A, which is barely enough to run a most 1500W heaters in normal conditions. So you could do this for years and never notice a problem.

But if you're on a 20A breaker/fuse get something heavier just in case. (Otherwise the extension cord is the weakest link.) There are specific circumstances where a device like a space heater can draw power over spec without shutting off. (I don't know why, I've just seen it happen.) Let the breaker handle it.

The "never use an extension cord with high draw appliances" bit is generally good advice for folks who have a bunch of these sitting around and can't read the fine print (often printed directly on the cord itself.)

The amp rating of the light switch is also something to check. (The amp rating should be printed on it somewhere... some disassembly required.)

I would consider replacing you (probably) 1500w heater with a 800-1000w unit and getting a Kasa Smart Plug instead of an extension cord. Give yourself some headroom for other stuff on the circuit. FWIW, both our home offices are on the same circuit and we have pretty regular "laser printer vs. space heater" arguments in the winter. :lol:
Oh, I have a lot of smart plugs around this apartment. Probably six or seven of them. But this one light switch that controls the desired outlet is right next to the light switch for the room, and I hit this light switch most of the time when I am turning that light switch on and off, so it would be less hassle to maintain.
maurvir Steamed meat popsicle
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I would be cautious, but DV is right. You can, if you choose the right cord, run a space heater. However, it will always be more risky than a direct connection.

You can, however, make your own cables with appropriately sized Romex, as that is literally what is in the walls. Get the industrial replacement plugs that are rated for 20A. Lastly, the other bit is also applicable. Unless that is the only thing on that circuit, you could be pushing the limit with a large enough space heater.
Malkin kick 'em in the face; taste the body
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At my old house, I had a small space heater on an extension cord. It was the baby's room which had no other source of heat and only a couple of outlets. I had to keep the heater away from the baby.

I didn't like it, but I used a quality cord and it was fine.

That being said, the small amount of convenience you'd gain doesn't really seem worth the risk to me.
A larger diameter conductor is safer. I’m using a 75 ft, 10 gauge Extension cord for my electric lawn mower. For electric motors in particular one wants as small a voltage drop as possible for efficiency.
DukeofNuke FREE RADICAL
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obvs posted:
DukeofNuke posted:
Just move the heater.
even 12 ga will get hot. It's all about the amps.
You mean move the heater behind the bed?

I mean, I'm no expert, but I wouldn't think having an eight-inch-wide space heater in a one-foot-wide space between the wall and a bed where two down comforters and a wool afghan blanket hang off of the edge of a bed over several power cables would be ideal.

The current empty corner where the heater sits by itself with at least a foot of free space around each side seems like it might be a better choice.

:shrug:

Well, since you didn't include a floor plan in your OP ...
and you asked for "thoughts", and moving the heater was my first one. :shrug:
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Can I use a space heater with a low-gauge extension cord?