Space Heater + electrical cord question

[QueBert]

I know this can lead to fires if you use the too small of a gauge cord. I see most companies that make space heaters recommending against using extension cords at all. Guessing because of the reason I mentioned.

I have a small one that's 1500w, The company that makes it sells a 13ft 14AWG cable. I have this electric cord.

http://www.amazon.com/gp/product/B004RH33RE?psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00

I know longer length cords with heaters are especially frowned upon. How do I calculate the proper extension cord I need here? I know when it's longer just being lower gauge doesn't automatically make it work. I'm not trying to burn down my house and shit. From what I gathered on Google if my cord was 15 or less feet I would be fine, but I'm pretty much screwed because it's 50 feet.

Is that about correct? I'm not trying to run this 24/7, or even all night every night. Just something to use a few hours a night to hold me over until the main heater in the house gets fixed in a few weeks.

 

[pcgeek11]

I would not use this with a cheap 50 foot extension cord. Yes the one in your link is cheap.

I would however with a short high quality industrial grade cord 15 feet or less with 12 gauge or larger wire and high copper content plugs.

 

[Howard]

A 12AWG extension cable will be fine. Your in-wall wiring is typically 14 AWG for a 15A breaker and 12 AWG for a 20A breaker anyway.

Note: I am not an electrician.

 

[Imp]

Not an electrician, in fact, I know almost jack hit about electrical stuff...

I think part of the danger is the connection. From what I've read, things seem to like to start melting/burning at the outlet where the thing plugs in. I've rarely heard of cords burning/melting in the middle of a run.

From very brief, uninformed research, the prongs are usually brass, which have a conductivity of 0.30 compared to copper?

Again, I don't know shit, and if your house burns down, not my problem.

 

[crashtech]

I'd use that cord with that load, but not unattended or when sleeping.

 

[NoTine42]

The idea scares me
You have to be absolutely certain there is air flow around the cord and nothing covers it or crimps it ...

There are heavier duty 10/3 cords available.

 

[Kneedragger]

Not an electrician, in fact, I know almost jack hit about electrical stuff...

I think part of the danger is the connection. From what I've read, things seem to like to start melting/burning at the outlet where the thing plugs in. I've rarely heard of cords burning/melting in the middle of a run.

From very brief, uninformed research, the prongs are usually brass, which have a conductivity of 0.30 compared to copper?

Again, I don't know shit, and if your house burns down, not my problem.

This is a major problem that needs to be thought about when using anything that is electric that draws a lot of current. The looser the connection the more heat is created with the connection. The longer this goes on the insulation will melt and the metal used will do the same. This is actually how a lot of house fires start. People buy those super cheap outlets in the bin at hardware shops. They suck and have loose connections or the connection becomes loose sooner.

 

[flexy]

What length extension do you actually NEED for the space heater?

Is there the option to have an electrician (if you can't do it yourself) just fit a longer, adequate gauge chord to the heater? Or probably use the 50ft chord you have, in its entirety or shortened, and fit it to the space heater instead of the supplied one which obviously is too short.

 

[Linux23]

not an electrician but 12-3 wire should be safe, but i would try and get a shorter cord length.

 

[crashtech]

Another common sense tip, other than the obvious of not using this setup unattended or while sleeping, is to check all the plugs for excessive heat once the unit has been operating for a while. If the plugs on the extension cord are getting more than moderately warm to the touch, there is too much resistance in the connection.

 

[natto fire]

This is a major problem that needs to be thought about when using anything that is electric that draws a lot of current. The looser the connection the more heat is created with the connection. The longer this goes on the insulation will melt and the metal used will do the same. This is actually how a lot of house fires start. People buy those super cheap outlets in the bin at hardware shops. They suck and have loose connections or the connection becomes loose sooner.

It is simple Ohms law. A high draw load is going to stress every connection in the system, exposing any resistance in the form of heat.

Resistance in the form of loose-fitting spring connections is very common, and is just another pawn in Ohm's law setup.

 

[dullard]

For short term use, I personally would just set it on low and not worry about it. Like others have said though, only leave it on when you are there.

Also, do you really need an extension cord? It'll still heat your home even if it is in a different room. Just leave the door open and get a big fan if you can.

 

[Kneedragger]

It is simple Ohms law. A high draw load is going to stress every connection in the system, exposing any resistance in the form of heat.

Resistance in the form of loose-fitting spring connections is very common, and is just another pawn in Ohm's law setup.

Yes I know, I'm an Electrician.

 

[skyking]

My preference with space heaters is to turn them down. If they have a 1000 watt setting I feel much better about using them unattended.
Make sure the outlet is in good shape as well as the cord.
Run the heater for a while and feel the cords at all connections including the wall. any defect in connection will feel hot to the touch.
Usually it is not the cord itself that is the problem it is a loose connection. Once an outlet heats up, the metal softens and the connection gets worse. Over not much time at all, some corrosion sets in and it gets exponentially worse.

 

[QueBert]

I would not use this with a cheap 50 foot extension cord. Yes the one in your link is cheap.

I would however with a short high quality industrial grade cord 15 feet or less with 12 gauge or larger wire and high copper content plugs.

While it isn't the highest quality cable out there, but cheap? It weighs a good bit more than my roommates 10AWG cable which is the same length. I have a box of cheap extension cords. This might not be an uber professional grade one, but it's far from cheap. I ran a big ass floor buffer with it for half an hour straight and it barely got warm to the touch.

 

[natto fire]

Yes I know, I'm an Electrician.

Oh, sorry you wound up here. Do you post at Electriciantalk? This forum is kind of a waste of time.

 

[crashtech]

Oh, sorry you wound up here. Do you post at Electriciantalk? This forum is kind of a waste of time.

Yet here you are. I waste lots of time, too.

 

[IBMJunkman]

I had a co-worker ask me about extension cords. He had a treadmill in the garage and was using it one day when he smelled something. The treadmill was plugged into an orange extension cord that was wrapped up like one does. I told him to bring it in. It had started to fuse into a single orange blob. I cut off the plug and looked at the wire. The wire size was smaller than standard lamp cord.

I figured the amperage draw of the treadmill was too much for the wire and it started heating up. Plus the cord being wrapped up made the whole thing act like a transformer just adding to the heat buildup. I think if the cord had been unwrapped and strewn around the floor it might have been OK.

I make my own cords. I buy heavy gauge cord, black rubber like sleeve by the foot from the DIY store and put my own heavy duty plug and socket on them.

 

[NAC4EV]

I know this can lead to fires if you use the too small of a gauge cord. I see most companies that make space heaters recommending against using extension cords at all. Guessing because of the reason I mentioned.

I have a small one that's 1500w, The company that makes it sells a 13ft 14AWG cable. I have this electric cord.

http://www.amazon.com/gp/product/B004RH33RE?psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00

I know longer length cords with heaters are especially frowned upon. How do I calculate the proper extension cord I need here? I know when it's longer just being lower gauge doesn't automatically make it work. I'm not trying to burn down my house and shit. From what I gathered on Google if my cord was 15 or less feet I would be fine, but I'm pretty much screwed because it's 50 feet.

Is that about correct? I'm not trying to run this 24/7, or even all night every night. Just something to use a few hours a night to hold me over until the main heater in the house gets fixed in a few weeks.

I am an electrician. And these are my thoughts.

Your Amazon extension cord has 100% customer satisfaction rating. That's very good.

Your heater will draw approx. 12.5 amps at load,
Normally a 12 gauge wire can carry 20 amps and can safely carry a 16 amps [80% load].

Your Amazon extension cord is rated for 15amps. This could be due the quality of the ends and the way those ends are attached to the cord.
The ends are the weak link and the source of trouble.

I prefer old school made up extension cords using industrial rated ends.

If you don't need a 50ft cord look for shorter one.

 

[stormkroe]

#14 quoted ratings usually apply to permanent install, inside walls with the possibility of contact with insulation, free air is a totally different ball game. As natto has said, the connection points will statistically be the only place to fail. Honestly, wire ampacity is vastly under rated, the idea of using a #10 for a 1500 watt heater is absurd.
@nac4ev, what do you mean that 12ga can carry 20a but safely carry 80% ? Is that an NEC thing or are you confusing the breaker loading with wire ampacity?

 

[NAC4EV]

nac4ev, what do you mean that 12ga can carry 20a but safely carry 80% ? Is that an NEC thing or are you confusing the breaker loading with wire ampacity?

In any circuit, the load placed on the supply wiring should never exceed 80% of the circuit wiring maximum current capacity.
Therefore you have a 20% headroom.

I hope this clarifies.

 

[Kwatt]

The cord the OP listed is only rated for 15 amps.

It will be maxed out.

Current rating is based on the wire size and insulation type.

.

 

[John Connor]

 

[tortillasoup]

I know this can lead to fires if you use the too small of a gauge cord. I see most companies that make space heaters recommending against using extension cords at all. Guessing because of the reason I mentioned.

I have a small one that's 1500w, The company that makes it sells a 13ft 14AWG cable. I have this electric cord.

http://www.amazon.com/gp/product/B004RH33RE?psc=1&redirect=true&ref_=oh_aui_detailpage_o05_s00

I know longer length cords with heaters are especially frowned upon. How do I calculate the proper extension cord I need here? I know when it's longer just being lower gauge doesn't automatically make it work. I'm not trying to burn down my house and shit. From what I gathered on Google if my cord was 15 or less feet I would be fine, but I'm pretty much screwed because it's 50 feet.

Is that about correct? I'm not trying to run this 24/7, or even all night every night. Just something to use a few hours a night to hold me over until the main heater in the house gets fixed in a few weeks.

If you're going 50 feet, get a 10-12ga cord. For 100 feet, absolutely need a 10ga cord.

 

[NAC4EV]

The cord the OP listed is only rated for 15 amps.

It will be maxed out.

Current rating is based on the wire size and insulation type.

.

The heater load is 12.5 amps