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20amp breaker, 15 amp switch feeding 20amp outlets... safe?

20amp breaker, 15 amp switch feeding 20amp outlets... safe?


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Old 11-03-13, 09:55 PM
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20amp breaker, 15 amp switch feeding 20amp outlets... safe?

If this has been asked before then please feel free to point me in the right direction, but I can't seem to find an answer to this online...

I have a 20amp breaker (in my house) feeding my garage (which is a separate building) with a switch in the house that can kill the power to the garage, the switch is 15amp rated. The outlets in the garage are (in order) a 20amp GFCI which feeds 2 regular 20amp outlets. All the wire is 12 gauge.

My question is... Is it okay to have a 15amp switch on a circuit that feeds all 20amp outlets? Or should I swap it out and put a 20amp switch in? What would happen if I put a 20amp load on the circuit in its current state? Would the 15amp switch meltdown?

Many thanks in advance.
 
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Old 11-04-13, 05:11 AM
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Replace it with a 20A switch.
 
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Old 11-04-13, 05:39 AM
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OT: The most wear and tear on a switch occurs at the moment it is flipped off. This switch will probably suffer no ill effects carrying 20 amps provided you turn off appliances plugged in downstream using their own switches before flipping this wall switch off.
 
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Old 11-04-13, 06:30 AM
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The proper thing to do is to replace the 15 amp switch with a 20 amp switch. The receptacles at the garage do not need to be 20 amp rated, but it's fine that they are.
 
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Old 11-04-13, 06:49 AM
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Thanks for the input guys, I kind of figured that it would make sense to change it out.

CasualJoe, you say that the outlets in the garage don't need to be 20amp? I'm curious to know why? What would have happened if I had 15amp receptacles in there instead of the 20amp? I'm guessing they would fail sooner than a 20amp unit if the load was too great.

I appreciate the comments, i'm fairly new to this and it's good to get an understanding of how these things work and what problems might arise from have mis-matched items.

Cheers
 
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Old 11-04-13, 07:07 AM
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CasualJoe, you say that the outlets in the garage don't need to be 20amp? I'm curious to know why? What would have happened if I had 15amp receptacles in there instead of the 20amp? I'm guessing they would fail sooner than a 20amp unit if the load was too great.
The NEC allows 15 amp devices on a 20 amp circuit as long as there is more than one place to plug in.
 
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Old 11-04-13, 07:08 AM
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What would have happened if I had 15amp receptacles in there instead of the 20amp? I'm guessing they would fail sooner than a 20amp unit if the load was too great.
All 15A receptacles, including GFCI receptacles, are rated 20A for feed-through. The 15A limit is for the load plugged into one device. Very few plug-in loads exceed that limit. Almost none. An 1800W hair dryer, one of the heaviest loads in any home, draws exactly 15A at 120V.
 
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Old 11-04-13, 07:59 AM
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Good to know Nashkat1 but it's unlikley I will be using a hairdryer in my garage. However I do have a DEWALT 1.6hp air compressor that at full load draws 15amps lol.

Slightly off my own topic but since you guys seems really knowledgable I had to ask....

I recently moved my old refridgerator into my garage which at full load is 6.5amps, and am thinking about putting a chest freezor in as my wife sells food for a living and carries many frozen samples. Would I be right in thinking it is best to put these devices on their own breaker? The combined load if I were to buy a chest freezor and install it now would be 16.5amps (5amps for chest freezor, 6.5amps for my old fridge and 5amps for a garage door opener) as I have 20amps to play with I guess I would be ok, unless I decided to use any tools then I guess that would trip the breaker. Are these correct assumptions?

Thanks again.
 
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Old 11-04-13, 08:21 AM
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Since you are now talking about appliances and power tools I think it would be wise to consider a 50 or 60 amp subpanel and several circuits to serve the loads.
 
 

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