Using PVC connectors and glue is often done, but not as strong or approved. If there will be any stress, I do not like it. The 3 piece was mentioned is best.

 

2 connectors and a coupling. Hope you have a ground wire with the pvc solution, (not recommended)

 

the two existing LT conduits' other end are buried, and possibly encased in some concrete below grade so my only choice is extension.

Let me be sure that I really understand what you have there before I try to answer some of your questions about it. Are you writing about Liquid Tight Flexible Metal Conduit? Or is the Liquid Tight Conduit which you have Liquid Tight Flexible Non Metallic Conduit. That will make a difference in how you work out your extension problem.

Second question, I need to connect three 1/2" LT connection to the bottom of a 4X4 weatherproof box that has three 1/2" threaded holes at the bottom. Theoretically this should work but there is an issue because the holes are so close together while the LT connectors are very bulky, so there is no way I can tighten the middle connector with a plier or a wrench because a wrench will not fit in between the first and third connector.

You can use a short rigid conduit nipple to drop the middle LT connector down below the other 2. That should give you enough room to work. Use a Liquid Tight to Rigid Connector, which has female threads, on to the bottom of the short nipple. A 2 or 3 inch nipple should allow you to leave the 2 outer LT conduits out of the way enough to be able to make the LTC up on the connector without too much cussin and swearing. Pairs of rigid to LT connectors with box connectors threaded into them will make a better looking coupling but the cost of the Rigid conduit to LT connectors may make it more than the improved appearance is worth.

If you use a larger box you can cut your holes far enough apart that you will have plenty of room to work. You can attach the connectors to the Liquid Tight prior to connecting it to the box. Just use 2 tongue and grove pliers, often referred to by the Channellock brand name, to tighten the compression collar down onto the connector's threads to secure the Liquid Tight to the connectors. Hold the connector still in the knockout hole with tongue and groove pliers and then use a locknut wrench to tighten the locknut on the connector. You will have more room to tighten the locknuts onto the connectors than you would to tighten the connector on the liquidtight. If the boxes are the weather proof hub boxes then I would suggest using 2 boxes if you don't want to buy a larger box.

Another workaround I can think of is to connect to the bottom of the box three PVC male adapters, then three pieces of short PVC conduits, then three female adapters to connect to the LT compression connectors.

Unless this in Non Metallic Liquidtight Conduit don't use PVC fittings with it. As soon as you share which type of Liquidtight Flexible Conduit you have there I can offer better advise on the rest of the aspects of the job.

Tom Horne

 

Let me be sure that I really understand what you have there before I try to answer some of your questions about it. Are you writing about Liquid Tight Flexible Metal Conduit? Or is the Liquid Tight Conduit which you have Liquid Tight Flexible Non Metallic Conduit. That will make a difference in how you work out your extension problem.


You can use a short rigid conduit nipple to drop the middle LT connector down below the other 2. That should give you enough room to work. Use a Liquid Tight to Rigid Connector, which has female threads, on to the bottom of the short nipple. A 2 or 3 inch nipple should allow you to leave the 2 outer LT conduits out of the way enough to be able to make the LTC up on the connector without too much cussin and swearing. Pairs of rigid to LT connectors with box connectors threaded into them will make a better looking coupling but the cost of the Rigid conduit to LT connectors may make it more than the improved appearance is worth.

If you use a larger box you can cut your holes far enough apart that you will have plenty of room to work. You can attach the connectors to the Liquid Tight prior to connecting it to the box. Just use 2 tongue and grove pliers, often referred to by the Channellock brand name, to tighten the compression collar down onto the connector's threads to secure the Liquid Tight to the connectors. Hold the connector still in the knockout hole with tongue and groove pliers and then use a locknut wrench to tighten the locknut on the connector. You will have more room to tighten the locknuts onto the connectors than you would to tighten the connector on the liquidtight. If the boxes are the weather proof hub boxes then I would suggest using 2 boxes if you don't want to buy a larger box.


Unless this in Non Metallic Liquidtight Conduit don't use PVC fittings with it. As soon as you share which type of Liquidtight Flexible Conduit you have there I can offer better advise on the rest of the aspects of the job.

Tom Horne

Tom, thank you. The existing LT conduits were installed many years ago and it's called SEALTITE, it is kind of a metallic core with a plastic shell outside.

 

I would use 2 normal straight fittings with a galvanized coupler. No idea if it's code though, lol.

 

If this is the same sealtight that the OP mentioned earlier. then you can extend it the best/easiest way you want. It's not a complete raceway, just a sleeve for UF wire. I would just use a coupler and be done with it.

 

If this is the same Sealtite® that the OP mentioned earlier. then you can extend it the best/easiest way you want. It's not a complete raceway, just a sleeve for UF wire.

How did you come to the conclusion that it is just a sleeve for type UF cable? The Discussion Starter did not say so.

I would just use a coupler and be done with it.

Do you mind telling which coupler your suggesting he use?

Tom Horne

 

Just use a female PVC adapter and glue it on the sealtight.