Change out a 15 amp breaker for a 20 amp?

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voyager

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Our house has only 2 electrical plugins on the exterior.
1 is solely for the use of the water pump.
It is inside the enclosure for the pump.
The other is on the screened lanai and is being used to run a freezer.
The 2nd receptical is blocked by the freezer's plug.

I have finally finished the replacement of the roof over the spa [hot tub for you northern tier residents], and we are now using it again.

The problem is that I have to run a 50' extension cord from the garage to power it up.

What I want to do is add an exterior outlet opposite from an interior outlet in one of the bedrooms.
It would be convenient for the spa and for her to use an electric string trimmer.

The spa requires a 15 amp minimum circuit.
The interior plugin is on a 15 amp breaker.
I want to replace the 15 amp breaker with a 20 amp breaker to better handle any possible load.
Is this OK without changing the receptacle's wiring?

I might do a similar addition in a few other locations to give more exterior recepticals if it is a viable idea.

I am not an electrician.
But, I played one in a high school play once.
 
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Our house has only 2 electrical plugins on the exterior.
1 is solely for the use of the water pump.
It is inside the enclosure for the pump.
The other is on the screened lanai and is being used to run a freezer.
The 2nd receptical is blocked by the freezer's plug.

I have finally finished the replacement of the roof over the spa [hot tub for you northern tier residents], and we are now using it again.

The problem is that I have to run a 50' extension cord from the garage to power it up.

What I want to do is add an exterior outlet opposite from an interior outlet in one of the bedrooms.
It would be convenient for the spa and for her to use an electric string trimmer.

The spa requires a 15 amp minimum circuit.
The interior plugin is on a 15 amp breaker.
I want to replace the 15 amp breaker with a 20 amp breaker to better handle any possible load.
Is this OK without changing the receptacle's wiring?

I might do a similar addition in a few other locations to give more exterior recepticals if it is a viable idea.

I am not an electrician.
But, I played one in a high school play one time.

The 15 amp breaker is sized to protect the 14 gauge wire. So no do not just change things.
It would best to run a new 12 gauge cable from the breaker panel on a 20 amp breaker.
 
15amp breaker= 14ga conductors.

20amp breaker= 12ga conductors.

And the recep. need to be GFCI.
 
Thanks neiltw and snoonyb.
I was afraid of that.
My first thought is that running new wiring up the wall from the breaker box, across the attic space, then down the wall to the receptical is a major operation, probably requiring the removal and replacement of sheet rock, then refinishing the wall's surface.
I may just continue using the extension cord, for a while at least.

EDIT:
Plus, the 15 amp breaker supplies several outlets in that bedroom.
They all would need to be rewired too.
Not gonna do that!
All the garage recepticals are on a 20 amp circuit.
The extension cord is a heavy duty leftover from my contracting days.
They are up to the job.
I just don't like doing it that way.
 
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Usually drywall removal is minimal. The wire can fished inside the cavity.
 
Do you know if the existing conductors are in fact 14ga.

You could also conduit around to the recep.
 
Yeah, tearing out dry wall is a no-go. If you'd of seen M'Lady's face when I mentioned that you'd understand.

But, I do like the conduit idea.
The breaker box has no empty slots for a new breaker to be installed.
But, we never use the dishwasher.
I could disconnect it from the electrical system, then use its 20 amp breaker to wire the outlet, fish it down the wall to the box, run it across the attic area, then into a conduit thru the soffit and down the exterior wall to a weatherproof GFI receptacle.

M'Lady's new electric string trimmer arrived today.
I'll order 2 more 50' 12/3 SJTW extension cords and several water tight connection covers tonight for her and another project I've got going.

While I have not verified that the existing wiring is not over sized, I have never seen a residential contractor use over sized materials except when a small amount was needed to finish a portion of a job and it was cheaper than going and buying a bunch more of the correct size. If I were a wagering sort, I'd put money on the fact that the wiring is not over sized. And, I won't waste the time and effort to find out.
 
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...I am not an electrician.
But, I played one in a high school play once.

And once I played in high school a "fireman" in a play responding to a fire where someone replaced a 15amp breaker with a 20amp breaker using 14 gauge wires. <<-- Sorry just a bit of humor here; but this can be very dangerous and I am very glad that you asked before you did something like this.

The best way as mentioned already is running a separate circuit. What ever way you end up doing it to please the wife.

Using an extension cord is not advisable though. Especially the longer you make them. Making them too long will lead to voltage drop and your spa will not get the sufficient power it needs to run properly and efficiently.

You say you do not have any breaker spaces left. Do you know the make and model of the panel. It may accept tandem breakers.

You say you will use a 12/3 extension cord. Do you mean 12/2 with ground? Only asking because 3 conductor plus ground is usually for 120/240 v applications and if this is the case you would need two breaker positions if the spa runs on 120/240v.

12/2 (14/2)is known as two conductors, one hot, one neutral and a ground - 3 wires total. The ground is assumed in this terminology.

12/3 (14/3)is known as three conductors, two hots, one neutral and a ground - 4 wires total. The ground is assumed in this terminology.

etc,
 
In order to tolerate a 20 ampere breaker, all of that branch circuit's wiring in the wall from the breaker panel on up to the various junction boxes and outlet boxes and switches has to be at least 12 gauge.

By running a completely new circuit for your spa you can be sure that it is all 12 gauge.

Since your spa needs 15 amps, you could run a 20 amp circuit so you can plug some lights in as well. But if there is any single item or appliance (here, the spa) that is wired directly into the circuit without a plug and receptacle and uses more than half the circuit's rating in amps, it is recommended that it have its own circuit and yet another circuit be run for the lights.
 
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In order to tolerate a 20 ampere breaker, all of that branch circuit's wiring in the wall from the breaker panel on up to the various junction boxes and outlet boxes and switches has to be at least 12 gauge.

By running a completely new circuit for your spa you can be sure that it is all 12 gauge.

Since your spa needs 15 amps, you could run a 20 amp circuit so you can plug some lights in as well. But if there is any single item or appliance (here, the spa) that is wired directly into the circuit without a plug and receptacle and uses more than half the circuit's rating in amps, it is recommended that it have its own circuit and yet another circuit be run for the lights.

all outdoors circuits shall be protected by a gfi
garage outlets shall be protected by a gfi
bathroom outlets are protected by a gfi
kitchen outlets is protected by a gfi, if within 4' of the sink



The only thing 14 gauge wire is good for is tying your ladder onto the pipe rack of your truck
NEVER, use 14 g wire when wiring a house
 
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all outdoors circuits shall be protected by a gfi
garage outlets shall be protected by a gfi
bathroom outlets are protected by a gfi
kitchen outlets is protected by a gfi, if within 4' of the sink



The only thing 14 gauge wire is good for is tying your ladder onto the pipe rack of your truck
NEVER, use 14 g wire when wiring a house


I try to never use 14 g on receptacles, unless I'm tapping off an existing 15A circuit, lighting is ok though in my opinion, since lighting loads are decreasing all the time with LEDs.
 
It is not a difficult job to cut small access holes in a ceiling to snake a wire through. Then just patch the small spots and re-paint.

Dave Mason
 

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