Emergency TIA needed ASAP for raintight EMT fittings

ptonsparky said:
A bit of RV silicone makes about any thing RT. The red stuff helps identify which ones you missed.
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Yeah seriously, a bead of silicone then tighten, that would work 1000 times better than this gaskets and allow tight fittings. I might just start doing that. BTW I care very little about water entry, it's that the fittings can't be tightened and/or will become loose when the gasket gets ruined by the weather.

It's kind of ironic, with all the obsession about grounding and bonding in the industry, then you have these things which make for absolutely horrible ground fault path.
 
electrofelon said:
Yeah seriously, a bead of silicone then tighten, that would work 1000 times better than this gaskets and allow tight fittings. I might just start doing that. BTW I care very little about water entry, it's that the fittings can't be tightened and/or will become loose when the gasket gets ruined by the weather.

It's kind of ironic, with all the obsession about grounding and bonding in the industry, then you have these things which make for absolutely horrible ground fault path.
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Seems if the bonding can or will be an issue adding alternative bonding such as a bonding bushing would be called for. 310.10 requires in part: "Metal raceways, cable armor, and other metal enclosures for conductors shall be metallically joined together into a continuous electrical conductor and shall be connected to all boxes, fittings, and cabinets to provide effective electrical continuity." No prescriptive how to do. And installation must meet 250.148, with many options but not limited. Generally code makes a requirement, but at times, how it is complied with in part can be up to the installer. If the equipment/devices/materials required for one application doesn't meet requirement for a different code, compliance can sometimes be made from within alternate allowances for compliance. such as a bonding nut or bushing in the case of complaint here.

AFA failure rate of the sealing device, that just seems to be one more incidence of poor QC and mfg. indicative and systemically rampant today. Also the inundation on the market of Cheap knockoffs only adds to the problem, when a mfg. is able to get a small part at a few pennies less when they are making 10's of thousand it adds to the profit for the mfg. and in some cases no concern for the ultimate longer term consequence of the product failure. Know of a nearby mfg. that was making a product that a fix to an issue was just a few pennies, but they felt it cheaper to defend a lawsuit than fix, and they were proved right, Sued and successfully defended. Another case even though they lost the penalty was much less than the profit they made. So why fix it!

Don't know the solution to the seeming lack of pride in workmanship epidemic we are experiencing the consequences of such as this complaint.
 
Sure we could blame the fitting manufacturers, but I blame UL. They are the ones that completely failed us here. One of several reasons why I'm pretty much never going to trust them again as the degree of their incompetence is unconscionable. I guess the NFPA too for starting the whole thing when there was a never an issue in the first place.
 
electrofelon said:
Sure we could blame the fitting manufacturers, but I blame UL. They are the ones that completely failed us here. One of several reasons why I'm pretty much never going to trust them again as the degree of their incompetence is unconscionable. I guess the NFPA too for starting the whole thing when there was a never an issue in the first place.
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UL only sets the standard not the QC of the MFG. Bad actors are out there, and the UL is limited when compared to the number of MFG. producing products. I know of large scale forged and just plain non compliant items being found and eliminated from the market place but I believe it only scratches the surface of what is being sent to us. UL has a means to report suspected noncompliant products. https://www.ul.com/resources/market-surveillance-departments
 
electrofelon said:
I have not investigated the wording of the product standard, but it should have language providing for construction that does not involve a fitting that needs to be wrench tight but has a soft rubber gasket on the mating surface. This is fitting 101.
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Haven't used one that had a soft rubber gasket the ones I've used had a fairly hard rubber that I was able to get wrench tight without over crushing the washer. I think compliance would be to UL-514B standards. UL-514B 5.21.1 indicated the sealing ring "shall be provided with a rigid means for retaining its shape when placed between the fitting and a knock out".
So if these fitting are deforming it would seem it would be a cause for a complaint to UL.
 
Fred B said:
Haven't used one that had a soft rubber gasket the ones I've used had a fairly hard rubber that I was able to get wrench tight without over crushing the washer. I think compliance would be to UL-514B standards. UL-514B 5.21.1 indicated the sealing ring "shall be provided with a rigid means for retaining its shape when placed between the fitting and a knock out".
So if these fitting are deforming it would seem it would be a cause for a complaint to UL.
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Okay but Robert Underwriter or whatever certainly had one of these at his desk to inspect and gave it the okay
 
Eddie702 said:
I mean how many years ago did they go for the gaskets on the RT fittings? 10-15 years??

Before that compression fittings had no gaskets and I don't recall many issues.

I'd rather have a fitting that I can tighten than the crappy gasket
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I think it has been closer to 20.
 
I just got in an order from Border States Electric of 1/2 and 3/4 raintight EMT connectors and couplings and they are pretty elaborate. Zinc compression ring, two different gaskets. One is black and the other is orange-ish. The exterior is blueish anodized color. Not just galv. I can forward a pic and manufacturer on Monday.
 
herding_cats said:
I just got in an order from Border States Electric of 1/2 and 3/4 raintight EMT connectors and couplings and they are pretty elaborate. Zinc compression ring, two different gaskets. One is black and the other is orange-ish. The exterior is blueish anodized color. Not just galv. I can forward a pic and manufacturer on Monday.
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Sounds pricey!
 
I almost never see rain tight EMT fittings (NPS thread) installed according to their 'listing', most of the time they are installed into a threaded HUB (like a conduit body or bell box) which they are not listed for (NPT thread). So if your going to void the listing by threading it into a hub, its not a huge difference to use a concrete tight fitting. I think the only thing a rain tight fitting is listed for is attaching EMT to a 3R sheetmetal box, like the side of a panel or enclosure.

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I got called to fix a malfunctioning transfer switch. The installing contractor had used EMT high on the building and then come down into the 3R transfer switch through holes cut in the top.

They had been pressure washing the building and water got in the raintight fittings somewhere up the line and deposited a bunch of water and old lube on the mechanism.

We just have to assume these junk fittings don't work, and all conduits will be wet.
 
Birken Vogt said:
I got called to fix a malfunctioning transfer switch. The installing contractor had used EMT high on the building and then come down into the 3R transfer switch through holes cut in the top.

They had been pressure washing the building and water got in the raintight fittings somewhere up the line and deposited a bunch of water and old lube on the mechanism.

We just have to assume these junk fittings don't work, and all conduits will be wet.
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In my opinion, 225.22 pretty much prohibits top entry. Maybe if you come down to a tee, with a drain in the bottom opening and then LB from the side opening into the top, it would be arranged to drain, but other than that, I don't see how you comply with 225.22. This rule was added in the 2002 code.
 
tortuga said:
I almost never see rain tight EMT fittings (NPS thread) installed according to their 'listing', most of the time they are installed into a threaded HUB (like a conduit body or bell box) which they are not listed for (NPT thread). So if your going to void the listing by threading it into a hub, its not a huge difference to use a concrete tight fitting. I think the only thing a rain tight fitting is listed for is attaching EMT to a 3R sheetmetal box, like the side of a panel or enclosure.

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They have the gasket and also an additional nylon ferrule that supposedly seals better than compression ring alone does. 99% of them are impossible to insert tubing into without completely disassembling as that nylon ferrule is nearly impossible to insert the tube through on first attempt, or even the 40th attempt and when taken apart is still difficult to slip that ferrule over the tube - the colder the ambient temperature is the more difficult it becomes in my experiences.

It's not just connectors, they also have RT couplings. No gasket but one of those nylon ferrules on each side of the coupling.
 
Its just amusing to me that every electrician I have ever met including myself use rain tight EMT threaded adapters to thread into a 'hub' like WP 'bell box' or an LB, which voids the listing. So when connecting to a HUB the listing is voided regardless if you throw that o ring gasket away or not.
 
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