Offset PVC with FMC??

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rszimm

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I've got a 2" PVC coming out of the slab behind the wall that'll hold the THWN conductors for a detached guest house. Unfortunately the flush mount panel is about 15" offset from where the conduit surfaces (my oops). What I've seen locally people do is put a female threaded PVC connector and then transition to FMC to protect the THWN as it zags over to the panel. Is this code compliant?

Is there a better way to do this? I actually saw a guy use some sort of propane torch thing, heat a piece of PVC up till it was like a noodle and then make his own offset fitting. I thought that was super cool, but I'm pretty sure that also wouldn't be code compliant or else everyone would be doing it.
 
rszimm said:
...I actually saw a guy use some sort of propane torch thing, heat a piece of PVC up till it was like a noodle and then make his own offset fitting. I thought that was super cool, but I'm pretty sure that also wouldn't be code compliant or else everyone would be doing it.
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Why wouldn't the heated and bent PVC be code compliant? We do it all the time. Here's a jobsite oven to do it easier if you do a lot of them: https://www.amazon.com/Greenlee-849-...31215866&psc=1

That said, I'd use whatever method was most convenient for materials and tools on the truck or nearby; and would probably use 22-, 30- or 45-degree elbows or even the FMC and a couple fittings.

An electrician looking at the totality of the situation will have several options. Does the exact method need to be engineered before he gets there?
 
Eddie702 said:
I have heated and bent 45s in 2" PVC using a heat gun with no problem. I don't think FMC is code compliant in a pvc run of conduit
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If it terminates in metallic enclosure (OP had a cabinet with panelboard we can probably assume is metallic and bonded) with proper metallic fitting then why should there be a problem with it? This is done quite often to go from PVC below grade and transition to RMC before emerging from grade for physical protection reasons.

If you had a length of PVC, then a short section of FMC or any other metallic raceway, then back to PVC you have code problems if you don't have some way to assure the metallic portion is bonded to the EGC.
 
Here's a video of the guy doing the heat thing with a piece of PVC (in this case it's for a swimming pool, but you get the idea).
Jump to 3m50s to see how flexible that thing gets. I'm going to have to give that a shot if I can find one of those torches. I'd imagine that pulling wires through the nice gentle sweeps will be much easier than a series of 45s or through FMC.
 
rszimm said:
... I actually saw a guy use some sort of propane torch thing, heat a piece of PVC up till it was like a noodle and then make his own offset fitting. I thought that was super cool, but I'm pretty sure that also wouldn't be code compliant or else everyone would be doing it.
Click to expand...

Everybody IS doing it. We bend PVC conduit all the time.:lol:

-Hal
 
rszimm said:
I've got a 2" PVC coming out of the slab behind the wall that'll hold the THWN conductors for a detached guest house. Unfortunately the flush mount panel is about 15" offset from where the conduit surfaces (my oops). What I've seen locally people do is put a female threaded PVC connector and then transition to FMC to protect the THWN as it zags over to the panel. Is this code compliant?

Is there a better way to do this? I actually saw a guy use some sort of propane torch thing, heat a piece of PVC up till it was like a noodle and then make his own offset fitting. I thought that was super cool, but I'm pretty sure that also wouldn't be code compliant or else everyone would be doing it.
Click to expand...

There’s a lot of electricians bending PVC conduit they even sell springs to install in PVC so it won’t kink or collapse during the heating process, I’ve seen guys use sand if they don’t have any springs also It is code compliant
 
German shepards said:
There’s a lot of electricians bending PVC conduit they even sell springs to install in PVC so it won’t kink or collapse during the heating process, I’ve seen guys use sand if they don’t have any springs also It is code compliant
Click to expand...

I have used a few pounds of compressed air, but for some reason I got laughed at for it here. :weeping: Greenlee even makes plugs for it.

-Hal
 
hbiss said:
I have used a few pounds of compressed air, but for some reason I got laughed at for it here. :weeping: Greenlee even makes plugs for it.

-Hal
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When you are doing 4"+ and doing lots of bends, what you explained is spot on, the air helps tremendously. I would add a jig table with water and rags to cool it.
Any PVC Does better with the ends plugged with at least a rag, keeps heat in and won't let it collapse as easy.
 
Don’t forget to take plugs out of both conduit ends before glueing , sounds like common sense but it happens ?
 
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