Burnt Outlet

This register type space heater... Does it still have the original factory correct cord with the molded-on factory correct plug? If not, DISCONTINUE USE OF THE APPLIANCE. If the cord and end are correct, DISCONTINUE USE OF THE APPLIANCE until this is figured out.

What is the wattage of the heater? There should be a plate or sticker somewhere on the device that gives this information.

heater is 12.5 amps and 1500 watts

"I" would only use that space heater on a properly installed 20A rated outlet wired with #12 AWG and a dedicated 20A breaker.

See http://cr4.globalspec.com/comment/755711 for more details.

Me too.

OP has a "landlord".

I thought 14 ga was outlawed.....In any case I would go with 10 or 12ga stranded thhn and a 20amp breaker and a 20 amp recpt.....

Don't use it, don't try to fix it yourself!

Check the power requirements of the heater. Depending on the AMP draw of the heater, it is probably drawing too much current.

NO! a 20 amp fuse SHOULD NOT be used to fuse a 15 amp circuit, or 14 ga. wire.

Look here.

Thanks for the quick replies.

Think I'll call the electrician in the morning.

I hope it's a different electrician this time. A 20A breaker on a 15A receptacle with #14 wire is a definite no-no.

Heck yeah.

You are a renter. It's the landlord's responsibility...and you should be able to run a space heater in any room in the house.

If you mess around and burn the place down, you're gonna be on the rent to own program, but there won't be a house.

I would not say you should be able to run a 20 amp service from any outlet. That is more wishful thinking than reality. However, if it was wired correctly you should blow the breaker not burn the wires.

I never use 14 gauge for anything else than small lights in a house.

In Cowboy city we do:

14AWG - 15 A
12AWG - 20 A
10AWG - 30 A
8 AWG - 40 A
6 AWG - 50 A
4 AWG - 70 A
3 AWG - 80 A
2 AWG - 90 A
1 AWG - 110 A
1/0 AWG - 125 A

This is all for copper wires only and specifics may apply.

I was visiting Florida and in one motel, I had trouble keeping any plugs in the receptacles, I hope it doesn't burn down when I am there.

"Year and half ago my landlord paid a licensed electrician ....." Are you sure this was a licensed electrician? I don't know of any licensed electrician that would put 14 ga wire on a 20 amp breaker, unless his sideline job is a professional arsonist!

As other's have said, unplug the heater, get another electrician (not the same one either) to make the proper repairs. And while he/ she is there have them inspect your heater, wouldn't hurt to have them check the current draw at the same time.

Have a Happy and safe New Year.

"Year and half ago my landlord paid a licensed electrician ....." Are you sure this was a licensed electrician? I don't know of any licensed electrician that would put 14 ga wire on a 20 amp breaker, unless his sideline job is a professional arsonist!

As other's have said, unplug the heater, get another electrician (not the same one either) to make the proper repairs. And while he/she is there, have them inspect your heater, wouldn't hurt to have them check the current draw at the same time.

Have a Happy and safe New Year.

The NEMA codes have been around for many years. The appliance manufacturers deliberately design devices to just barely be able to be used in the common 15 amp rated outlets. No one designs a product to be slightly above what is legal, they build to use as much current as they can, to do the desired job as quickly for the consumer as possible.

Yes, but as pointed out by the post I was replying to, if you figure at 125% for a single largest load then it is above 15A - I was suggesting this modification be enacted. Let's face it - with a space heater on a circuit, even a 20A one, you really don't want another appliance to also be plugged in. Before we were busy enough that I could be a full time control engineer, I also had to double as Maintenance Supervisor and I was quite tired of mid January breaker resets in the office areas.We need to redefine the codes on these much abused devices. (we outlawed them per company rules in our offices here)

Agreed for sure. But if 15 amp circuits were outlawed, along with 14 and 12 gauge wire, the appliance manufacturers would suddenly start selling 3500 watt heaters, and the circuits would overload from them.

What I am trying to say is that as the code writers try to correct issues, manufacturers will adapt to take every advantage they can.

Most assuredly they will. But we have one consumer appliance here right now that has been abused for at least 20 years now. Not suggesting outlawing 15A receptacles and AWG 14 wire - just making some appliances (space heaters specifically) 20A only.

I understand abuse can still occur even with such a change, because I see our new building has at least 4 duplex 20A receptacles in one room, apparently on one circuit, so 2 space heaters on the same circuit is a definite possibility here. But, at least it would be a start in the right direction.

The electric fireplaces they are pushing on QVC is another one for concern as these are also 12.5A devices. My wife has purchased 2 of them and I was very sure to see she didn't overload any of our circuits. How many people would think about this? Can you imagine someone getting 2 of these and trying to run them in the same room on the same circuit? I am sure it is happening.

" I was suggesting this modification be enacted"

Having worked in the design and QC sections of a manufacturing co. I believe the industry in general, No matter how NEMA codes are modified and rewritten, products are and/or will still be barely meeting set standards! I believe this to be true considering that All manufacturers are in the business to make profits! And to maximize their profits therefore will be cutting corners! Specially those electrical /electronic products that are manufactured in China, Taiwan, Mexico, etc., and other offshore countries.

The only time products may or will be in accordance with good manufacturing practices is when the intended customers are part of the Federal government? Which in this case we know have a very different pricing structures!

Just a slight addition to your post, in case anyone wants to do that.

Make sure any wire nut joined wires are inside the receptacle box, otherwise, put them in a junction box.

does a nurse have to install it??

Best answer of all...

GA.

DirtyPhoenix,

All the necessary & important stuff has been said with one exception,that electrician nearly killed you and yours.

I started to write "nearly started a fire..." but the reality is there was/is a fire,how else does something get 'burnt'!?

IMHO I would notify the city/county jurisdiction and make a report.

Because the licensed electrician may or may not be actually licensed and the landlord may or may not have known this.This means other families/buildings could be at risk.You could be saving someone's life.Consider this when anyone tries to argue against making a formal report.

To summarize the mechanical issues,

14g wiring is rated for a max continous amperage of 15.That's 1800watts of energy.Your heater should not have been at issue.

Circuit breakers are there to protect the wiring from more energy than it is capable of safely carrying (thus protecting the building).

If the circuit breaker is rated for 20amps,the wiring connected to it Must be also.

Any device (recepticle or switch or ??? etc. ) must be rated to handle the energy that could be supplied by the wiring used.14gage = 15amps. 12gage = 20amps

There might also be issues with aluminum and copper wiring,anytime aluminum wiring is used,a specific connection procedure must be used (IIRC) and the use of a 'joint compound' specifically for Al wiring must also be used.

Hope this helps

J

By code the breaker should be 15 amp. Since the heater draws 12.5 amp, nothing should have burnt. Maybe your "electrician" used one of those outlets where you poke the wire in and it gets friction to not come out. They are dangerous. Always use one that has a screwed down terminal.

"The wire is too burnt to read any writing,"

perhaps it is 12 gauge?

I have always found 1500 watt heaters challenge the molded plugs and then damage the receptacles. I have found many hot plugs on heater cords, and the heater cords are often lighter than 14awg, so the heater cord also warms up - therefore do not cover the cord!

I agree with the hospital grade specification for the receptacle especially if you are using it for a heater.

By the way, is the landlord aware of you using a space heater? In our area that will be contrary to most tenancy agreements - due to hydro costs and fire risk.

Good rule to live by

Way I read it was that it was just an additional outlet (undedicated), which the OP used for a space heater.

If I understand you statement correctly:

The wire feeding the outlet is size 14 AWG and is not burning nor suffering heat damage.

The front of the heater cord is suffering heat damage/burning and the recepticle/outlet the heater is plugged into is also suffering heat damage.

This being the case the issue is with the plug body and heater cord not the outlet.

Most likely the plug has loose and/or high resistance connection(s) causing excessive heating and the heat is being transferred to the outlet contacts.

Have the damaged outlet replaced and the heater cord assembly including the cap replaced with a properly sized UL listed cord or get rid of the heater and purchase a new unit that pulls 12.5 amps or less.

If your understanding / assessment is correct, then I will look and concentrate on the contact resistance between the heater plug and the outlet terminals.. Even on normal usage, contacts wear and tear occur, that even it is rated as a hospital grade outlet, it is normal for the contact resistance to increase and the tendency to loose its contact tension.. This is the same reasoning why all hospital outlets are mandated to be checked for its contact (resistance) tension annually... or automatically be replaced if it fails or below the minimum 4 oz. contact tension test...

Farther aggravating this loose electrical contact scenario is the electrical and physical condition of the electric heater's power plug. I assume was never been replaced from the time it was put in service? In this case it will be normal for the circuit breaker to trip due to an increase in current brought about by the loose connection condition...

I am thinking that the worst problem the OP is having started with a poor connection at the receptacle. Either a loose wire, or a poor fitting plug on the heater. I have some of these heaters that are older than dirt. Made before the safety switches were mandated. Still with the factory installed plugs on them. They work just fine in 15 amp receptacles. The cords might get warm after hours of use, but not warmer than human skin.

The electrician may have used 14 gauge wire, and should have used a 15 amp breaker, BUT, the components should have not gotten hot enough to have damaged the wires as he stated.

Agree..

The OP claimed it was replaced 1.5 years ago and that was probably with a cheap replacement too!

I agree and you are obviously correct if ohms law is the only concerned.

Basically what I'm referring to, which by the way didn't come out very clear, sorry for that..

I'm referring to a condition that exist in a confined arcing environment, where electrodes are also in close proximity with one another as in an electrical plug.. In this particular situation, the arcing, beside melting surrounding nearby conductors, the heat also generates carbonized materials from surrounding insulation materials... this combined carbonized material thus in turn will create additional path for an electrical short that eventually will trip the circuit breaker.

Luckily for the OP the protective CB worked as expected in this particular incident!. It may even be worst if the protective device malfunctioned, turning into an electrical that may also turn deadly! This scenario I described was the same situation I experienced in one of the smoky hospital electrical fires while working in NYC!

OK! If something was burned due to arcing, then you could be right: an additional path through carbonized plastic or carbon deposits could add additional current.

If that is the case, then the outlet and plug must both be replaced, and likely some wire too.

I have to add agreement with others: This is the landlord's responsibility, and even a qualified engineer resident should have the landlord arrange the repairs, to avoid liability.

"the protective CB worked as expected in this particular incident"

I did not see any refrence to the OP stating the CB had tripped.

3 days later we are all rambling on like some old ladies tea club.

And the OP hasn't been back since Jan. 3, the time of the original posting. Just wonder if his place burnt or a stray electron took out his computer or are we just ....

I don't know that this applies. But I have seen it many times on heater and fans. Where people will unplug them while they are still running and plug them back in with them on. At 12.5 amps as the plug is pulled from the or pushed into the receptacle. It causes arcing on the contacts. This will lead to pitting and carbon build up. That causes a poor connection that can heat up and burn the receptacle and plug.

I do agree that the wire is not rated for the 20 amp breaker in most areas.

If the wires were properly fast to the outlet terminals and the 12.5 amp rating of your heater is correct then there should have not have been a problem. The heater pulling just a little more the 80% of the wires load capacity.

My space heater had a factory molded plug that was defective. It worked just fine for the first year and then it started doing the same sort of thing, but the cord had always been warm to the touch.

I cut off the molded plug and replaced it with a plug from the hardware store. The cord has never been warm since.

I cut away the plastic from the original plug and found that only half of the wires were clamped. No wonder it got hot!

The moral of the story is this. The building probably underwent more quality control than the space heater did. And with only 2 wires, I didn't need to pay an electrician to do anything. I doubt the minimum wage flunky on the plug forming production line resembled anything close to an electrician either, but it ain't rocket science.

"I doubt the minimum wage flunky on the plug forming production line resembled anything close to an electrician either, but it ain't rocket science."

I doubt he had a wage comprable to the US minimum wage either.

Somehow it is a lot easier to pull the plug from the wall outlet by just grabbing on the cord! By doing so it becomes a very common problem for the wires to become loose from the plug whether it is the molded type or not!