Home>Discussions>ELECTRICAL & LIGHTING>Changing 15amp breaker to 20amp
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scfd529
Changing 15amp breaker to 20amp

I recently got a different air compressor with a bigger motor and compressor unit. When i have it going it will trip the breaker for my garage after a short period of time. The circuit for my garage only has a 15 amp breaker for some reason. On that circuit there is a single plug-in inside the garage, an outdoor plug-in that is in the eve of the house (i recently added it for christmas lights only), the garage door opener, and a single ceiling fan in an adjacent room that had apparently been added later (there is a junction box in the circuit that it's coming off of). From what i could see, it looks like 12 gauge wiring coming off that breaker in the breaker box and to the plug-in inside the garage. On that plug in there is 12 gauge in the push lock ports and 14ga coming off of one of the screws (unsure where it's going). I am judging gauges by the wire size differences. My question is...with what's on the circuit and my issue of the breaker tripping, am i safe to switch the breaker out to a 20amp breaker since i have 12ga wire coming off the panel and to the plug-in i will be using? I feel that it'll be fine but wanted a second or third or fourth opinion.

JLMCDANIEL
Re: Changing 15amp breaker to 20amp

Changing to a 20 amp breaker definitely would not be to code because the breaker must match the smallest component in the circuit (the 14 ga. wire). If you disconnect the 14 ga wire or replace it with 12 ga. you would probably be good to go.
Jack

NEC
Re: Changing 15amp breaker to 20amp

^^^^^ What Jack said.

sparky1
Re: Changing 15amp breaker to 20amp

if the 14 gauge wire is just a "tail" in the box, and its wire nutted to some #12 you could change out the breaker.i believe the tap rule will allow you to do this. if it makes ya feel better you can even change the 14 in the box for piece of mind if yad like. the big thing is to make sure you dont have any 14 wire runnning from box to box.

NEC
Re: Changing 15amp breaker to 20amp
sparky1 wrote:

if the 14 gauge wire is just a "tail" in the box, and its wire nutted to some #12 you could change out the breaker.i believe the tap rule will allow you to do this.

You can use 15amp devices on 20amp circuits but not #14 taps to feed them.

Re: Changing 15amp breaker to 20amp

Run a dedicated 20A circuit to the air compressor. Its the safest and cheapest fix to this problem. Replacing the breaker will lead to major issues down the road (not to mention the code violation). Plus, what if you want to run something in addition to the compressor?

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