Spot check my logic here... upgrading outlets from 15A to 20A

[Jawn]

Howdy y'all,

First garage upgrade will be sufficient "juice" to run my compressor or other misc tools (120v 20A circuit).

See the pic for the basic layout - this is apparently a newer circuit run by a previous owner. Garage is in the basement, so the ceiling is open joists and walls are (currently) open studs but will soon be drywalled once everything else is squared away.

To explain the image... brown represents the breaker box. The yellow represents romex cabling. It goes from the breaker and up through the joists to the conduit of the first outlet, down the conduit to the quad box, then back up the conduit and into the joists again, across the stud wall, to a blue plastic in-wall box for four more outlets. Currently it's run with 14-2 and 15A outlets. I want to up-rate it to 12-2 and 20A outlets.

Now, I think it's only a 1/2" conduit... I can go bigger, but at the same time I've read that romex in a conduit is a no-no... but some say it's ok for a short run like that? So do I put a junction box at the top of the conduit, run romex to there, individual conductors to that quadbox, then more romex to the other box, or do I just replicate the existing wiring (just with larger wire)? Next question, do I daisy-chain the outlets in each box, or do I wire nut two short pieces of wire to the incoming wire, and connect each of those to each duplex outlet?

 

[theoldwizard1]

I want to up-rate it to 12-2 and 20A outlets.

Now, I think it's only a 1/2" conduit... I can go bigger, but at the same time I've read that romex in a conduit is a no-no...

Not true ! NM (Romex) cable is allowed in conduit as long as the conduit is of the appropriate size.

Because you are going to use the first box as a "junction" to continue the daisy chain, your NM cable will have to go down and up, unless you put a junction box
at the top of that conduit.

I know for sure that 1/2" conduit is not adequate to 2 12-2 NM cables. Not certain if you will need 3/4" or 1" in order to meet code.

do I daisy-chain the outlets in each box, or do I wire nut two short pieces of wire to the incoming wire, and connect each of those to each duplex outlet?

Garage also requires GFCI, either a breaker or the first outlet in the daisy chain. If you have a GFCI breaker, then either way you are proposing is acceptable. With GFCI receptacle, you must daisy chain and it must come off the screws marked "LOAD"

 

[pattenp]

You can up the circuit to 20A using the #12 wire but the 15A outlets are fine to use on a 20A circuit. The 20A outlets also have a sideways slot for a true 20A plug, but the thing is most if not all appliances and power tools that use 120V use a regular straight blade plug. So you are wasting money buying the 20A outlets, but that's my opinion.

 

[Speedy Petey]

My opinion is not to "upgrade" anything. Leave what's there and add the 20A circuit that you need. NO REASON to rip out what's there and re-do it.

And I agree with patt. 20A receptacles are a waste unless you need them for something specific.

 

[Charles (in GA)]

Pattenp is correct, code only requires you to have more than one receptacle on a circuit to use 15 amp receptacles on a 20 amp circuit. If you had only one, and I mean a single receptacle, not the typical duplex receptacle (which counts as two by the code) then it would have to be a 20 amp rated receptacle.

If you use good quality receptacles, they probably have 20 amp insides them anyhow, with a 15 amp faceplate snapped on to them.

This is a 15 amp rated receptacle, with a 20 amp contacts inside it. The manufacturers do this for convenience of manufacture. You will find this in virtually all brands of receptacles, the commercial, industrial, or spec grade recepacles.

This is a 20 amp rated receptacle, note the cross slot in the face plate. The cross slot is on the neutral pin. In a 20 amp 240v receptacle, the cross slot is on the other pin. This is also a Hubbell of the same back wire design as the one in the pic above, but this one is 20 amp rated due to the front that is installed on the receptacle at manufacture.

These duplex receptacles are counted as TWO receptacles by the code.

***

With regard to Romex in conduit, while legal, it is a royal pain to pull if going any distance. You may need to use lots of pulling lube on it and have someone pushing and feeding it if you are going any distance.

Charles

 

[Jawn]

Not true ! NM (Romex) cable is allowed in conduit as long as the conduit is of the appropriate size.

Good to know. So I guess I can either replace the conduit or put a junction at the top, whatever's easier?

Garage also requires GFCI, either a breaker or the first outlet in the daisy chain. If you have a GFCI breaker, then either way you are proposing is acceptable. With GFCI receptacle, you must daisy chain and it must come off the screws marked "LOAD"

I did not know that. Only GFCI outlets in this place are in the kitchen and bathrooms. It was built in 1985 though, so maybe that's more recent code? I have thought about putting a third box into the mix, so that'd be a convenient place for a GFCI outlet.

You can up the circuit to 20A using the #12 wire but the 15A outlets are fine to use on a 20A circuit. The 20A outlets also have a sideways slot for a true 20A plug, but the thing is most if not all appliances and power tools that use 120V use a regular straight blade plug. So you are wasting money buying the 20A outlets, but that's my opinion.

I wanted to go with the proper 20A outlets as a visual indication to anyone else that sees it that it is indeed a 20A circuit, and I plan to put the proper 20A plug on my compressor.

 

[Jawn]

My opinion is not to "upgrade" anything. Leave what's there and add the 20A circuit that you need. NO REASON to rip out what's there and re-do it.

Actually, there is. I'm out of room in the breaker box. So I'm just going to nix one 15A circuit and replace it with a 20A circuit.

 

[Stuart in MN]

I did not know that. Only GFCI outlets in this place are in the kitchen and bathrooms. It was built in 1985 though, so maybe that's more recent code? I have thought about putting a third box into the mix, so that'd be a convenient place for a GFCI outlet.

I just checked online, and Georgia adopted the 2011 NEC as of January 1, 2012. They don't appear to have any amendments to the NEC (states often will modify or change parts of the NEC to suit their needs) so that means you will need GFCI protection in the garage.