Swap out a 15 amp breaker for a 20 amp beaker

[flatbutt]

Can I, SHOULD I do this myself?

I have a new AC floor unit that maxes out at 15 amps. I don't have a dedicated line for it so it's likely that it'll trip on startup or when the compressor kicks in.

I'm no dummy but neither am I egregiously stupid. So yea or nay?

[masraum]

The work of changing out a breaker is simple.

It's the "should" that would concern me. I'm not sure what the rules are for wire gauge and circuit size that governs whether a circuit is/can be rated for 20amps.

My guess is that chances are that it wouldn't be a problem if you did it, but it would also suck to start a fire.

[rockfan4]

There's a good chance the AC unit doesn't actually draw 15 amps. I'd try it as is first and see what happens. If you do need to upsize the breaker, you need at least 12 gauge wire to safely handle the load. If the wire is 14 gauge, don't do it.

[908/930]

Originally Posted by rockfan4

There's a good chance the AC unit doesn't actually draw 15 amps. I'd try it as is first and see what happens. If you do need to upsize the breaker, you need at least 12 gauge wire to safely handle the load. If the wire is 14 gauge, don't do it.

This. The breaker is sized to protect the wire, not the appliance.

[Bill Verburg]

Originally Posted by flatbutt

Can I, SHOULD I do this myself?

I have a new AC floor unit that maxes out at 15 amps. I don't have a dedicated line for it so it's likely that it'll trip on startup or when the compressor kicks in.

I'm no dummy but neither am I egregiously stupid. So yea or nay?

It's easy to swap the breakers but the purpose of the breaker is to protect the wire
15 amp for 14 wire
20 amp for 20 wire
etc

[flatbutt]

Did not know that about wire gauge. THANK YOU!

[wilnj]

Unless copper was very cheap when the house was built, it’s unlikely that a 15amp circuit has 12ga wire.

Or (like me) reals of 12ga is what the electrician on one your jobs handed you so 12ga is what you used.

My retired electrician uncle was nearly apoplectic seeing yellow romex everywhere.

[MBAtarga]

Originally Posted by Bill Verburg

It's easy to swap the breakers but the purpose of the breaker is to protect the wire
15 amp for 14 AWG wire
20 amp for 12 AWG wire
30 amp for 10 AWG wire
etc

a correction and added 30 AMP

[Chocaholic]

So, 14 AWG wire is white?
12 AWG wire is yellow?
10 AWG wire is paisley?

[cabmandone]

Originally Posted by Chocaholic

So, 14 AWG wire is white?
12 AWG wire is yellow?
10 AWG wire is paisley?

For the newer stuff yeah pretty much although I'd say the #10 is "orange". But in older homes they can all be white.
__________________________________________________ _____________

FB, if the unit is rated at 15 amps that's typically "locked rotor amps" which only occurs on startup. Once the unit is running the amperage will drop. As someone else suggested, I'd plug it in and see what happens.

[MBAtarga]

Mike - there are recently introduced "new" colors for 3 conductor wire. But the customary colors for 2 conductor wire are white, yellow, orange, black - for 14, 12, 10 and 8 AWG.

Google:
The new Romex NM-B cable color coding, introduced in 2024, uses blue for 14/3, purple for 12/3, and pink for 10/3 cables. These new colors differentiate 2-conductor and 3-conductor cables, making it easier to identify cable type and gauge. Traditional colors for 2-conductor Romex (white for 14/2, yellow for 12/2, orange for 10/2, and black for 8/2 and 6/2) remain unchanged. [1, 2, 3]
Here's a more detailed breakdown:
New Colors (2024):

• 14/3 NM-B: Blue jacket
• 12/3 NM-B: Purple jacket
• 10/3 NM-B: Pink jacket [1, 2]

Traditional Colors (No Change):

• 14/2 NM-B: White jacket
• 12/2 NM-B: Yellow jacket
• 10/2 NM-B: Orange jacket
• 8/2 and 6/2 NM-B: Black jacket [1, 2, 3]

Purpose of New Colors:

• The new colors help distinguish 2-conductor (traditional) and 3-conductor (new) Romex cables. [1, 2]
• This makes it easier to identify the specific cable type for different applications, such as 3-way switches, split receptacles, multi-way lighting, and appliances requiring multiple hot conductors. [1]
• The new color coding also simplifies wiring for electricians and helps inspectors ensure compliance with NEC regulations. [4]

AI responses may include mistakes.

[Bill Verburg]

Originally Posted by Bill Verburg

It's easy to swap the breakers but the purpose of the breaker is to protect the wire
15 amp for 14 wire
20 amp for 20 wire
etc

My bad
20amp wants 12 gauge wire

[dad911]

I kept coils of white 12awg & 3 wire so newer 'repairs' don't stand out.