Compression Fittings on Rigid Outside

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clarice

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In Hawaii it is common practice to use compression fittings - couplings and connectors - on rigid conduit in exterior applications. Recently an engineer from the mainland questioned me about this practice and asked for the UL listing that certified the fittings for "wet" locations. The fittings that I used are marked "concrete tight", but I have not found a listing for "wet" locations. Does any manufacturer have such a listing?
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
You won't find that listing for rigid as it is not required...if it were you could not use standard threaded couplings.
Don
 

chris kennedy

Senior Member
Location
Miami Fla.
Occupation
60 yr old tool twisting electrician
don_resqcapt19 said:
You won't find that listing for rigid as it is not required...if it were you could not use standard threaded couplings.
Don
I had a guy call today and ask the same thing about EMT. He has 4" Emt run outside with compression fittings.

So my question is where do you find comp. fittings listed for wet locations?
 

infinity

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Location
New Jersey
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Journeyman Electrician
These are from ETP:

RaintightFamily.jpg


http://www.etpfittings.com/

I'm sure that other manufacturers make them too.
 

LJSMITH1

Senior Member
Location
Stratford, CT
Most, standard EMT/RIGID compression fittings no longer have the raintight listing. Initially they did, but after many field reports of wet conduit runs and boxes, UL pulled that requirement. Now they are only listed as concrete-tight.

Some manufacturers have added a seal inside the fitting to make the compression fitting suitable for raintight use. These are listed with UL for use in applications requiring a raintight fitting. I would make sure you use these in an outdoor application.

http://www.bptfittings.com/catalog/catalog_families.asp?tp_id=33&category_id=302&family_id=355

They should have the internal seal to be raintight. A standard compression fitting will not be raintight. There have been too many variables with the different conduit manufacturers for a reliable compresssion seal to withstand a rain test. In addition, I would use a zinc fitting over a steel fitting in an exterior application. They hold up much better for corrosion resistance.
 
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