DIY wiring, 4 wires in conduit to inside garage Romex

[CaptainJ]

I'm planning on DIY wiring install for my new 3. I have a subpanel and 200amp service. The panel is outside the garage and I need about a total 40' run. I'm a bit unsure about the wires. I'll use a 50amp breaker with a 14-50 outlet. I believe I'll use PVC conduit on the outside with 4 separate wires from the subpanel until I can pierce the wall into the garage (about 10' of conduit). I'll need some kind of junction box there I think to go through the wall into the garage. From that box I'm thinking I can use Romex inside the garage to the outlet.

Is that a good plan?

 

[P85_DA]

Not sure I understand u are going to run THWN than Romex? If u are running wire from main panel why not just run THWN/THHN Direct to a sub panel in garage u will just need three wires ..from sub panel u than have option to run a four wire 14-50 or do a three wire WC

 

[CaptainJ]

Not sure I understand u are going to run THWN than Romex? If u are running wire from main panel why not just run THWN/THHN Direct to a sub panel in garage u will just need three wires ..from sub panel u than have option to run a four wire 14-50 or do a three wire WC

I already have a subpanel right next to the main and they are on the outside of the house and maybe 10' away from the garage wall so I thought I'd have to use about 10' of conduit from the subpanel to a spot on the outside wall where I can go through the wall into the garage and from that spot I'd use Romex inside the garage to the rear of the garage where I'd put the 14-50.

 

[P85_DA]

U should be able to use romex all the way for 14-50 I’m not sure what code is in ur area but where I’m at doesn’t need disconnect

 

[CaptainJ]

Some of the run will have to be outside so I thought I'd use THNN in the outside conduit. Maybe romex in the conduit is ok. I'm sure there's code for all of this but I'm looking for DIY and the safest method without reading the code. I'm assuming layman speak for safe means it's probably meeting some standard acceptable code in general.

 

[P85_DA]

Not sure when u go thru wall how much further you need to go for 14-50 if plug is opposite of where u punch thru wall run THWN all the way ..I’m still not picturing how u will transition from from Thhn to Romex without another sub panel ..or if that is even allowed ..it’s best to run THHN/THWN all the way

 

[CaptainJ]

Ok, so the transition from THHN to romex is where a subpanel needs to be? I thought I'd use some kind of box mounted just inside the garage where I'd connect the THHN to the romex and then run the romex to the end of the garage where the outlet would be. It sounds like I should just keep the same wire (romex) and run it through the outside conduit all the way to the point where I go to the end of the garage and then punch through the wall to the 14-50 outlet. The pics might explain where everything is.

 

[P85_DA]

Yes I would just run one type of wire all the way ..I don’t believe Romex even In conduit is legit as not rated for wet conditions ..I would just run THWN all the way ..since ur wall is not fully dry walled it looks easy to run conduit to that location

 

[CaptainJ]

Just one more question about conduit then, I still need to run this on the outside wall because I can't get to the inside of the house from the panel (or I don't want to tear up the inside to do that). So THWN is ok in the outside conduit vs romex?

 

[P85_DA]

Yes THWN is weather rated THHN u would run in conduit all the way ..Romex even in conduit is not rated for wet condtions ...can’t u run conduit all external up to the point u need to punch thru wall for plug ?

 

[CaptainJ]

yes, I'll just run conduit all the way on the outside. I think I've got my plan. Thanks for your help!

 

[P85_DA]

yes, I'll just run conduit all the way on the outside. I think I've got my plan. Thanks for your help!

Only other alternative if u want Romex is use the punch out on back of box and run in wall ( no conduit) all the way that will be code compliant ...u will just need to use a long flex drill bit to get thru the studs

 

[CaptainJ]

I'd like to have hidden wiring but too many studs so conduit will work for this application.

 

[Krazaak]

Ok, so the transition from THHN to romex is where a subpanel needs to be? I thought I'd use some kind of box mounted just inside the garage where I'd connect the THHN to the romex and then run the romex to the end of the garage where the outlet would be. It sounds like I should just keep the same wire (romex) and run it through the outside conduit all the way to the point where I go to the end of the garage and then punch through the wall to the 14-50 outlet. The pics might explain where everything is.

Romex is not rated for use in conduit at all.

 

[xyeahtony]

Romex is not rated for use in conduit at all.

would it hurt though? surely something that doesn't need conduit would benefit from extra protection

not that i would know, im not a electrician.

 

[Rocky_H]

Romex is not rated for use in conduit at all.

That is utterly false. Why do so many people have this misconception?
Code specifically does allow that Romex can be run in conduit if needed for protecting it from damage in some locations. The thing about the original question is that I don't quite remember if it's allowed to use Romex to penetrate an exterior wall. I think that might not be OK.

 

[P85_DA]

if it's allowed to use Romex to penetrate an exterior wall. I think that might not be OK

Correct as romex is not rated for wet conditions ...

 

[Krazaak]

That is utterly false. Why do so many people have this misconception?
Code specifically does allow that Romex can be run in conduit if needed for protecting it from damage in some locations. The thing about the original question is that I don't quite remember if it's allowed to use Romex to penetrate an exterior wall. I think that might not be OK.

Appreciate the correction. I did some research when I installed my HPWC (I used THHN) and recall seeing many statements that Romex wasn't allowed in conduit. I didn't realize it was a topic of such hot debate, but it sounds like it is indeed allowed, just not in exterior locations.

 

[davewill]

I like your plan as I think using one run of wire is better, but there's no reason I know of that you can't transition from THHN to Romex. You just need a junction box that's not hidden (behind drywall, for instance).

 

[CaptainJ]

I finished it up and it works. Nothing has burned down. I used 6awg from Home Depot, 40' ain't cheap x 4 wires. A 50amp breaker and pvc pipe. So, happy to get that out of the way.