Changing 15Amp Breaker to 20Amp

[bpatters69]

Hello All,

I want to change the breaker in my garage from 15 to 20Amps. I plan to hire someone to do it as I am not comfortable with electricity. Anyway, it should be pretty straightforward for someone who knows what they are doing. Does anything else need to be changed?

Thanks, Bill

[EricU]

It seems really unlikely that the wire is rated for 20 amps.  So the garage would need to be rewired.  How accessible is the wiring?

[MT Woodworker]

Why do you want to go to 20 amp?

[Roly]

It seems really unlikely that the wire is rated for 20 amps.  So the garage would need to be rewired.  How accessible is the wiring?

+1     It may just as easy if not cheaper to add a 20a circuit.   Roly

[Admiral]

Hello All,

I want to change the breaker in my garage from 15 to 20Amps. I plan to hire someone to do it as I am not comfortable with electricity. Anyway, it should be pretty straightforward for someone who knows what they are doing. Does anything else need to be changed?

Thanks, Bill

You need to check the gauge of the wiring in the garage.  It is likely 14ga for a 15 amp service, and 20amp service requires 12ga wiring to meet code.  It is possible, but unlikely, you have 12ga wiring in the garage, so the earlier suggestion of just running a new 20 amp line might be the way to go here.  When put a subpanel in my shop, I wired the wall circuits with 12ga to get 20amp service everywhere.

[MT Woodworker]

You need to check the gauge of the wiring in the garage.  It is likely 14ga for a 15 amp service, and 20amp service requires 12ga wiring to meet code.  It is possible, but unlikely, you have 12ga wiring in the garage, so the earlier suggestion of just running a new 20 amp line might be the way to go here.  When put a subpanel in my shop, I wired the wall circuits with 12ga to get 20amp service everywhere.

Plus 1
Do not overload your wiring 
Fire in the walls would not be good

[srv52761]

As mentioned, in all likelihood you will need to run new wiring.

As labor will be the major expense, seems wasteful to pay the labor to run a 12g wire.

Run 2g copper or aluminum and put in a sub panel.  Odds are good you will be looking at electric or hybrid auto sometime in the future.


If you decide to go 12g consider running 12-3 and have the electrician install a multi-wire branch circuit.   That would give you two 20 amp circuits in the space of one.

Detached or attached?  If detached, any change may require a sub panel or mwbc.

[bpatters69]

Why do you want to go to 20 amp?

I bought the Dewalt DW735 Planer and I was planning Poplar. I connected the planer to a Stanley 6 Plug, power strip and it tripped the breaker on the power strip. The strip is old so I don't know how many Amps it is rated for. I am guessing 15 at best. Along with the planer, I have 3 shop lights that are also plugged into the strip and they were all on. I should not have connected the planer to the strip, I should have connected it directly to the outlet. I looked at the breaker and it is a 15Amp breaker. 

I did run the planer after I connected it directly to the outlet vs the Stanley power strip. The breaker never tripped so that was good. I never take much off on any pass. I usually only turn the wheel 1/4" turn which is less than 1/16" of an inch.

I am probably over reacting as the planer is new but if I can change the breaker to 20Amp without much fuss, I will do it. According to the manual, the planer only needs 15Amps but I have read that it is better to use it with 20Amps.

Thanks, Bill

[bpatters69]

It seems really unlikely that the wire is rated for 20 amps.  So the garage would need to be rewired.  How accessible is the wiring?

Thanks. I thought the wire might be an issue. When we re-modeled the house in 2010 our contractor wired the garage for 220 for my table saw and also for my dust collector. I can see there are 20Amp breakers in the panel but I know that does not mean that all of the wiring can support 20Amp.

[Snipe Hunter]

Don't use the power strip