Raintight fittings

jimport

Senior Member
Location
Maryland
I was thinking the other day, if a raceway outside is considered a wet location by default and the conductors are rated for wet, why is there a need for raintight fittings vs regular compression fittings? We also know that condensation will occur inside the conduit so I feel I must be missing something.
 
I was thinking the other day, if a raceway outside is considered a wet location by default and the conductors are rated for wet, why is there a need for raintight fittings vs regular compression fittings? We also know that condensation will occur inside the conduit so I feel I must be missing something.
You are not missing anything. It is dumb. As you note, the conductors are already required to be wet rated, plus we have 230.3, 225.22, 314.15, and 312.2. Also, raintight fittings are not manufactured with sufficient quality or tolerances to actually be raintight.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
I think it's a matter of minimizing the water. Moisture in an enclosure is one thing, being filled with water is another. Arranged to drain is important, too.

I usually drill two 1/8" holes in the bottom of WP boxes, LBs, etc.where normally sealed.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
I was thinking the other day, if a raceway outside is considered a wet location by default and the conductors are rated for wet, why is there a need for raintight fittings vs regular compression fittings? We also know that condensation will occur inside the conduit so I feel I must be missing something.
Good question, I would guess that this falls in line with the NEC moving towards what someone thinks is a good idea versus a substantiated need for something like rain-tight fittings. Rain-tight probably allow less water infiltration but they still do not keep it all out so what's the point. Setting the installation up so that it properly drains is more important than the flimsy rubber ring on these fittings.
 

jimport

Senior Member
Location
Maryland
The ones I was using had a 1/16" metal ring with a slight shoulder in addition to the concrete tight compression ring.
 

ActionDave

Moderator
Staff member
Location
Durango, CO, 10 h 20 min without traffic from wing
Occupation
wire pulling grunt
It goes like this..... If you have something you want to sell all you have to do is make friends with someone on one of the CMPs and convince him or her that what you have needs to be required by code. "Sounds like a good idea to me", says Mr. CMP member, "Besides, it's not costing me anything". Next thing you know you have an instant market for your product.

It sounds like I'm being sarcastic but I'm not. It really does go down this way.
 

jaggedben

Senior Member
For what it's worth, in Mexico every EMT fitting I saw outdoors was set screw. They seem to be surviving, although I saw other stuff there that made me truly worry.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
A local ec in Chapel Hill, NC got turned down for using compression fittings on the ceiling of a screened in porch. I could not find anything saying they were rated for damp location. The call, IMO, was a bs one. Does this guy really thing water was going to get in thru the compression fitting? Sometimes we have to use our brains and put the book down. I really try and do things correctly but that call was unwarranted but perhaps correct according to the wording in the NEC
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
I think the whole idea of raintight fittings is silly.
They don’t work, joints leak, and as said above, everything is wet rated.
Someone here honestly tell me he has pulled out wire from a below ground pipe (that wasn’t coil HDPE) that was completely dry after two or three years.
as also stated above, manufacturers come up with another bull crap product and convince a CMP member to support their proposal.
 
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