Electrical question

[Square Wheels]

I had a nightlight GFCI plug in my bathroom.  It tripped and the reset button would not go back in.

I went to Home Depot to get a replacement, and since it was right in front of my face, I couldn't find it.  So I found someone to help me.  He asked 15 or 20 amp, I said, "Ummmm, dunno, does it matter?".  He said if you have a 20 amp breaker, then a 15 amp plug is a no go.  He showed me the 15 and 20 amp version.  The plug on the 20 amp was totally different so I knew it was the 15.  That was mistake 1.  I was the one who put the last one in.

So, I get home and start doing the flip off all the 15 amp breakers until I got the right one game.  Hmm, none of those, so I started on the 20 amp breakers.  Sure enough, it was one of those.  While replacing it I saw that the wire was 12/2.  Now for mistake 2, about 5 or 7 years ago when I remodeled the bathroom, I added on another plug to the GFCI.  I ran 14/2 to that plug (seriously, what homeowner has 12/2 in their basement ready to use?).

The last GFCI made it for at least those 5 or 7 years with lots of people taking hot showers in a small bathroom.

Am I going to burn my house down because of the mismatch in amperage?

[petitepedal ★]

[Parsnip Totin Jack ★]

I'll wait for TK to show up. He knows this stuff.

[Mr. Silly]

23 minutes ago, Square Wheels said:

Am I going to burn my house down because of the mismatch in amperage?

Yep.  Sucks to be you.

[Square Wheels]

4 minutes ago, Mr. Silly said:

Yep.  Sucks to be you.

Hmm, thanks.  Maybe we should go away for the weekend then.

[Wilbur ★]

18 minutes ago, Old#7 said:

I'll wait for TK to show up. He knows this stuff.

He is a little too amped up for me.  I say, go with the fire hazard. 

[Ralphie ★]

2 minutes ago, Wilbur said:

He is a little too amped up for me.  I say, go with the fire hazard. 

With a rebel yell, he said mho, mho, mho.

 

[maddmaxx ★]

Your house will not burn down because of that extra outlet.

 

 

 

 

as long as you don't use it.

[Longjohn ★]

36 minutes ago, Square Wheels said:

seriously, what homeowner has 12/2 in their basement ready to use?).

[Longjohn ★]

45 minutes ago, Square Wheels said:

Am I going to burn my house down because of the mismatch in amperage?

Don't plug a space heater or blow drier in the outlet with the 14/2 and your good.  It will be fine for phone chargers and electric razor.

[Ralphie ★]

7 minutes ago, Longjohn said:

Don't plug a space heater or blow drier in the outlet with the 14/2 and your good.  It will be fine for phone chargers and electric razor.

When my FIL and I installed kitchen cabinets in our laundry room, he told my wife they should be fine as long as she didn;t put anything too heavy in them.

 

[Mr. Silly]

39 minutes ago, Old#7 said:

I'll wait for TK to show up. He knows this stuff.

Or you could test it out by peeing on it.

[Longjohn ★]

1 minute ago, RalphWaldoMooseworth said:

When my FIL and I installed kitchen cabinets in our laundry room, he told my wifre they should be fine as long as she didn;t put anything too heavy in them.

 

My kitchen cabinets started to pull apart because they were loaded so heavy with dishes.  My wife moved everything to a cabinet that I built and put plastic ware in the one that was trying to pull apart.

[Ralphie ★]

1 minute ago, Longjohn said:

My kitchen cabinets started to pull apart because they were loaded so heavy with dishes.  My wife moved everything to a cabinet that I built and put plastic ware in the one that was trying to pull apart.

I have a corner one that is hanging by aboot one screw.  I really should fix that before it falls.

[2Far ★]

HD guy is prolly right.

With the 20 breaker you can run 19+ amps though a device only rated for fault protection to 15 amps. Electricity can be a harsh and fickle mistress.

Make the trip.

[Reverend_Maynard]

I'm not an electrician, but I think most are wrong on this one.

Because a 15 amp outlet won't let you plug a 20 amp device into it, you should be fine to run 15 amp outlets on a 20 amp circuit.  However, by code, you are supposed to use the wire rated for the breaker, not the outlet (consider that you could run 2 10amp appliances off of one 15 amp outlet and not blow the breaker, so you have 20 amps running through the wire).  So, you should either replace the wire (12/2) or the breaker (15 amp), the outlet is fine.

 

ETA: A little googling seems to suggest that what I have stated is code in most places in the US.  As long as there are multiple outlets on the circuit, you can use 15a outlets on 20a breakers.  Wire must be sized to the breaker for all applications.

[Thaddeus Kosciuszko]

Reverend Maynard is correct.   Clearly and succinctly stated, I might add.

He also correctly stated that he related what is code for most places in the US.  Massachusetts has its own supplements to the National Electrical Code, and I'm not familiar with what changes may apply here according to the Massachusetts code supplements.

You do need to either replace the breaker or to replace the wire. 

Some other considerations:

The first thing - did you determine why the GFI initially tripped, and why it wouldn't reset?  Replacing the outlet may not necessarily be the solution to your problem as the tripped GFI may only be a symptom.

If the bathroom outlet is the only outlet on the 20 amp circuit, it must be a 20 rated receptacle.  If there is at least one other outlet on the circuit, then the Reverend's advice applies and you are permitted to use 15 amp rated outlets on a circuit protected by a 20 amp breaker.

Of the two choices you have - replacing the breaker or upgrading the wire - replacing the breaker would likely be faster and easier.  But that probably means you'll be messing in the main panel, so you better shut off the main breaker before you muster the courage to take off the panel cover.  If you have a spare 15 amp breaker in the panel, you could just move the wire from the 20 amp to the 15 amp breaker.  If you have to buy a 15 amp breaker, get exactly the same manufacturer and type breaker as the 20 amp breaker - do not mix manufacturers.  The panel inside cover should list the types or model numbers of breakers that properly fit the panel.  Take a picture of the writing on the 20 amp breaker and the list on the panel cover, and match them up with what you're buying at the store.

The other choice is to replace the wire with 12-2, which may be the better choice for you.  You had the skills to install the 14-2 in the first place, so removing it and installing the 12-2 is essentially the same.  Remember that 12-2 wire is heavier and stiffer, and more difficult to fold back into the box to put the outlet back in.  This puts more strain on the outlet as the wires resist being pushed back into the box, which can in turn crack the outlet or loosen the wires where attached to the screw terminals. 

If you pre-form some bends in the #12 wires before you push the outlet back in, that helps reduce the strain on the outlet.  If you use the side screw terminals, make sure the wire goes at least 3/4 of the way around the screw terminal and that the wire is fully under the screw head.

[Square Wheels]

Wellllll, there may be a little more to the story than I let on.  I suspect running a light / fan in a bathroom off of a GFCI is not permitted.  When I sell, that's the way it was when I moved in, and that's the story I am sticking too.

So, those 14/2 wires are impossible to replace without tearing apart the bathroom.  Replacing the 12/2 all the way from the garage is equally impossible.

So, to make the safer, I should replace the breaker with a 15 amp breaker?

[Longjohn ★]

Listen to TK, he's the one that went to electoral college.

[maddmaxx ★]

6 minutes ago, Longjohn said:

Listen to TK, he's the one that went to electoral college.

I always think of him as a shock jock.

[Longjohn ★]

1 minute ago, maddmaxx said:

I always think of him as a shock jock.

Oh geeze, shock jock reminds me of what I had to wear with my compression stockings before my surgery.  I'm sure glad I don't have to wear those anymore.

[Further]

The breaker protects the wire, 12 awg wire can handle 20 amps, 14 awg wire can handle 15 amps. As long as that stretch of 14awg never carries more than 15 or hell, use the safety factor and call it 17 amps, you should be fine.

And we're talking about a few dollars worth of wire, it burns up WTH, no big loss. Of course if the house catches fire when the wire fails....

So...ya feelin lucky......well are ya ?

[Square Wheels]

I have my tooth brush in the plug, a light with 7 or maybe 10 watts of LED light, then the bathroom fan.  That's it.  

[Further]

1 minute ago, Square Wheels said:

I have my tooth brush in the plug, a light with 7 or maybe 10 watts of LED light, then the bathroom fan.  That's it.  

You're safe, but that wire is hidden in the wall for the life of the house. Highly unlikely to ever cause a fire, but fires are pretty major events.

[Square Wheels]

So, at some point I should simply put in a 15 amp breaker?

[Wilbur ★]

7 minutes ago, Square Wheels said:

So, at some point I should simply put in a 15 amp breaker?

I thought you would be smouldering ooze on the basement floor by now..   

[Square Wheels]

Just now, Wilbur said:

I thought you would be smouldering ooze on the basement floor by now..   

So far so good, we just won't use that bathroom any more.

[Further]

21 minutes ago, Square Wheels said:

So, at some point I should simply put in a 15 amp breaker?

The issue with that is that down the road somebody's poking around in the panel, sees the 12 awg wire on a 15 amp breaker and says to themselves 'somebody  put the wrong breaker in, I'll fix that' and we're back to 20 amps on 15 amp wire.

Hang a tag on the wire stating that the circuit has 14 awg wire in it.

I didn't think a few amps would be much of a concern until I witnessed insulation melting off wire from a few amps difference. In conduit it's not that big a deal, romex in a stud wall could burn down the house.

[Thaddeus Kosciuszko]

57 minutes ago, Square Wheels said:

So, at some point I should simply put in a 15 amp breaker?

Yes.

As far as the rating of the wire:

Type NM (Romex) wire has conductors rated up to a temperature of 90C.  Technically the rating of a 14AWG conductor covered with insulation rated 90C is 25 amps. 

Your circuit breaker has a trip rating of 20 amps, but depending on the the type of load it could trip anywhere from 16 amps and higher (which is a discussion for another day).

Combining those two facts with the circumstances that would cause a breaker trip, it is unlikely that your 14-2 wire itself would start to burn up if subjected to a 20amp load.  Note I did not say it would be impossible.

So, while that may make you feel a little better about what's installed and maybe let you worry less, that doesn't make the installation code compliant.  And the Code has been developed over the years to make electrical installations safe.  The Code limits the use of 14AWG wire to circuits protected with a fuse or breaker rated at 15 amps, for good reason.  There are many older installations with insulation with much lower temperature ratings where it would indeed be unsafe to run 20 amps through such a wire.  Given many older buildings are added to and remodeled, the limitation keeps people safe.

7 hours ago, Square Wheels said:

I suspect running a light / fan in a bathroom off of a GFCI is not permitted.

You can run anything you want off the load (protected) side of a GFCI receptacle.  You're not required to run a bathroom fan off of a GFCI unless the fan is within the footprint of a shower or tub.

1 hour ago, Square Wheels said:

I have my tooth brush in the plug, a light with 7 or maybe 10 watts of LED light, then the bathroom fan.  That's it.  

The wire should be selected to match the electrical load (yet another discussion for another day).  In homes the wiring is either rated to carry 15 amps or 20 for typical household circuits.

Many people think the breaker is selected based on what load will be on the circuit, but not really.  Since the designer or installer never knows how much will be plugged in to a circuit, the breaker is selected to protect the wire.  The load determines the wire size, which determines the current rating of the wire, which then in turn determines the breaker trip rating.  Load the circuit up as much as you want, because a properly operating breaker will open to protect the wire and protect you in the process.

 

Don't beat yourself up over this, SW.  Believe me, I've seen much worse, and that installed by people who had the experience and training to know better.

 

[Square Wheels]

Thanks all.  It's been like this for many years, but I will put a new breaker in at some point.  I have no idea what else may be running off that breaker, but for the 14/2 I installed, it's only one plus.  The fan can't be drawing much at all and the light is close to nothing.