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Discussion Starter · #1 ·
Hi I am running an wall unit ac that is 115v 12 amps on a 20 amp breaker with 12/2 wire. Why is the outlet that has the AC pluggled into it melting? All other outlets on the circuit appear to be fine. There are 9 recepticles that are rated 15 amp on the circuit. We have a flat screen tv, cable box, xbox, phone, desktop computer and wall unit AC all running off this 20 amp breaker. The AC unit is on the last recepticle on the circuit. Does the AC need to be on its own circuit or should we change the recepticle to a GFI? Any suggestions welcomed.
 

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That is a lot of draw on one poor 20amp circuit. My window AC units 'want' (in the manual) their OWN ('Dedicated') 20amp circuit.

You're cooking that last outlet for a reason. Time for another circuit. Or put your AV system on a different one.
 

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what is the outlet rated for? if its only a 15 amp outlet i would replace it with a higher rated outlet. seems like you have too much stuff on this circuit also
 

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I wouldn't bother with a 20amp outlet unless your AC needs it (you would know because of the weird plug).

You do want a high quality outlet. But a 20amp is not necessary.
 

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Gfi

No, the GFI would not solve the problem. The problem lies in the amount of power drawn on the circuit. Too much power drawn through a 15amp circuit can cause it to overheat.

I agree with everyone above, changing the A/C unit or AV equip to a different circuit would be the solution to the problem.
 

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A GFI would not help this. A GFI is designed to limit shocks.

Loose connections cause heat and heat draw appliances like heaters and motor startups can make the situation worse. Were the plugs loose or the connections to the screws or backstabs?
 

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Discussion Starter · #8 ·
The plug was in great shape and the house is only 9 years old we are not running anything the prior owner wasn't running which is why I couldn't figure out why this was happening we did run the AC unit last year also. My husband said all the wires are nice and tight and the outlet itself was good until this of course.
 

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Have you changed the receptacle and then the second one also melted too or are you saying the one is melting and so far nothing has been done? If the plug on the A/C is just the ground and two parallel straight pins then it only requires a 15 amp receptacle. Change the receptacle with a commercial grade unit, not one of the 69¢ ones from WalMart.
 

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Replace the receptacle with a commercial or industrial grade one, and lightly sand the prongs of the AC plug to remove any corrosion. The problem is that the connection between the prongs and the receptacle has abnormally high resistance, probably due to looseness and corrosion.
 
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Discussion Starter · #11 ·
We have not changed any recepticle yet. He was wondering if changing the recepitcle to a better grade or changing all 9 recepticles to 20 amp was the thing to do.
 

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Discussion Starter · #12 ·
we have taken the computer equipment off the circuit too hopefully this cut some juice being taken? Yes or no
 

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Removing any load like the computer will lessen the amp draw on the circuit. This will not help your situation at the end of the run. It would however help if the breaker were tripping. Only the load from the AC is flowing at the end of the run.

You do not want to install 20 amp T-slot receptacles on your circuit. It would be a code violation if the circuit was only 15 amps. Also unless the cord had the T-cap it would not be needed.
 
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even at 20 Amps the receptical should not melt! at 30Amps maybe.. but the breaker in the panel would have tripped. so, i would think you have a problem either:

1) high resistance at the melting receptical. this is usually caused by a lose connection, or corrosion. this is easily fixed.

2) intermittent connection which is causing arcing (which also generates a lot of heat but will NOT trip a "normal" breaker unless it is an arc detection type like is found for bedrooms)

3) the load is greater than 20Amps and your breaker is not working properly (it should trip off).

if it were me.. the first thing i would do is turn on the loads (one at a time) and goto the panel and put a clamp on meter on the load cable to measure the current draw and confirm it is less than 20A (preferably less than 80% of this so... should measure 16A or less). then this would eliminate item #3.

then i would turn OFF the power, pull the receptical and inspect for obvious signs of WHERE the heat is localized and determine if it is just bad connection or arcing. if i find bad conection i would cut the wire and and strip back the insulation a bit so you have nice fresh copper and connect again to a NEW receptical (they are cheap, so don't worry about it).

if none of the above helps, i would call an electrician..

Knucklez
 

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You have a bad connection(s) in that outlet. IT could be the outlet itself, OR the molded plug on the A/C unit. ... or both.

Sometimes, you will have to change =both= to remedy the problem.
 

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kbsparky said:
You have a bad connection(s) in that outlet. IT could be the outlet itself, OR the molded plug on the A/C unit. ... or both.

Sometimes, you will have to change =both= to remedy the problem.
Sparks brings up a good point. Do take a close look at the cord and plug.

You don't know what the former resident was doing. Maybe they only turned on the AC when the other stuff was off.

There IS a problem that needs to be uncovered.
 

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I have found that once an a/c cord has started to melt, along with the receptacle outlet, both have to be replaced, or else you will just melt your replacement outlet as well.
 

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My money says it's a stab-in outlet.:no::whistling2:
 

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Too much draw on the rest of the circuit would not cause
the outlet to melt.
Only problems with the ac units receptical.
Replace both the outlet and the plug on the ac unit,
Use the best quality you can find.
This may cost a little more in the short term,
But in the long term you will have a reliable unit.
Dont use back stab.
 
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