Getting water out of a conduit?

[jymbee]

We want to reuse a buried 2 inch conduit that currently has a 6 line phone wire in it and install a new coax cable for Internet/phone. For whatever reason the electricians are unable to pull the current cable out. It breaks before it comes free. One theory is that it may be glued to the conduit in some places.

In any event, the conduit is around 300 feet long we are able to blow air from one end to the other which obviously means it's not entirely blocked but when trying to get a pull line through (bag + plastic string) it doesn't make it as we can hear water in the line-- not enough to completely block it but enough to keep the string from going through.

Someone suggested we get the type of large compressor where you can build up pressure then release it all at once and BLAST the water out. Willing to try just about anything to keep from having to retrench. Any suggestions?

 

[CobyRupert]

We want to reuse a buried 2 inch conduit that currently has a 6 line phone wire in it and install a new coax cable for Internet/phone. For whatever reason the electricians are unable to pull the current cable out. It breaks before it comes free. One theory is that it may be glued to the conduit in some places.

In any event, the conduit is around 300 feet long we are able to blow air from one end to the other which obviously means it's not entirely blocked but when trying to get a pull line through (bag + plastic string) it doesn't make it as we can hear water in the line-- not enough to completely block it but enough to keep the string from going through.

Someone suggested we get the type of large compressor where you can build up pressure then release it all at once and BLAST the water out. Willing to try just about anything to keep from having to retrench. Any suggestions?

2" is a pretty good size conduit for a phone wire or coax. Any chance conduit could of been crushed or there is a right angle
fitting in the line somewhere? Seems like a crushed conduit would still pass a lot of air.

Doesn't seem likely it would be glued?
What do you mean it breaks before it comes free? Does it breaks more than once? Seem like it would break once and then come free? Or maybe break again if pulling from the other end and then come free? If so, put the two pieces together to see where in the length of conduit the cable is snagged, that's the one spot that needs to be retrenched to fix your crushed conduit.

 

[My Gym]

Is it a straight run. If it has a corner it was most likely why the wire broke. Use a 240' Tuff-Grip Fish Tape, Model Number: 31-057 | Menards® SKU: 3643671

$66.98 Feed it as far as you can from each end, measure . The then dig cut and splice conduit. using fish tape as you go.

 

[Soundguy]

agreed with previous post(s)

 

[Daver1963]

Conduit blower system. You use a CO2 tank and it puts high pressure into the conduit. I've used them on 500ft runs of 4" conduit. Water is no obstacle. I've seen it blow water so hard it went through a 4X4X4 handhole and the water went into the conduit that was on the other side of the hole.

 

[rgr33]

I doubt if the cable is glued, the conduit is put together with fast drying glue well before the cable is pulled. It sounds like some measuring and exploratory digging is the answer. I suspect conduit is crushed somewhere in the run.

 

[jymbee]

Ah, don't know what I was thinking-- it's not a 2" conduit. Smaller-- I think inch & a quarter. (half?) There is one right angle but with a sweep type elbow.

The darned phone cable in there is a mess to work with given the slippery shielding and all. The end we're pulling (or trying to pull) from has a vertical section going up a utility pole and the electricians (who have done this a million times) use a heavy pulley to get the a straight angle and pull with a small pickup truck. The wire ends up just coming apart between truck & pole.

Should also have mentioned that if we have to end up retrenching it would need to be on a different path (or shallower depth) given this is just one of several conduits in the same trench which also contains other phone wire, primary power line for house down the line, and so forth. No way to I want to dig into that!

2" is a pretty good size conduit for a phone wire or coax. Any chance conduit could of been crushed or there is a right angle
fitting in the line somewhere? Seems like a crushed conduit would still pass a lot of air.

Doesn't seem likely it would be glued?
What do you mean it breaks before it comes free? Does it breaks more than once? Seem like it would break once and then come free? Or maybe break again if pulling from the other end and then come free? If so, put the two pieces together to see where in the length of conduit the cable is snagged, that's the one spot that needs to be retrenched to fix your crushed conduit.

 

[jymbee]

Yep, I bet that thing would do it! BUT... not sure where I could find anything like that around here to rent one...

Conduit blower system. You use a CO2 tank and it puts high pressure into the conduit. I've used them on 500ft runs of 4" conduit. Water is no obstacle. I've seen it blow water so hard it went through a 4X4X4 handhole and the water went into the conduit that was on the other side of the hole.

 

[EarPlug]

Why not just use Direct Bury coax cable?

 

[Industrial Toys]

Are we talking PVC ridged conduit? Did you say how long?

I have run into this enough times before. It's always a mystery. The glue idea just does not hold water (pun intended). The conduit is probably damaged, or maybe there is a stone in there acting as a wedge.

I don't like the idea of water in a conduit, but that's just a fact in some cases. As mentioned, don't even worry about it and just go with underground COAX.

 

[Coyote machine]

The water indicates a break or crush spot, IF the 'ends' are not open to weather, on either end. Usually the pull string is attached to the wire/coax/whatever and then pull lube is put in the conduit to ease/reduce friction on the item being pulled. The pulley rig and truck are attaching to just the wire and no pull string to keep the wire from breaking outside of the conduit. And if there is a crush spot(s) the wire being pulled will be destroyed if not stretched in it's jacket, enough that you'll have to run another piece of it too.

Use the fish tape to determine where the blockage is and hand dig the area and fix the break/crush. Before spicing in new conduit, you could run a pull string from the broken area in both directions, to ensure you get the string through the entire conduit. Just put the string through the repair section too so when you splice it's one continuous pull string/cable of choice/need. Once everything reaches both ends, put the splice together with correct glue for the conduit.

 

[jjlite]

Use high psi CO2 to blow the water out. If the wire was pulled in using wire lube or dish soap then it has glued itself to the inside of the conduit. The water is your problem. If your using a shop vac and a light weight pull string with a piece of light weight plastic it will still go bye a kink in the conduit ,but if you have water in there it will go no where. Also if its rigid conduit corrosion will stick the existing wire good. Good luck.

 

[JerryK]

Almost all underground conduits condense water from the air, even if sealed with monkey chit on each end [ clay like putty ]. We used to drill a small weep hole in rigid conduit run in a low spot to let the water out during installation. Also, some folks put the wire into PVC pipe while they are gluing the 10' sections together... too lazy to suck a mouse/pull cord thru the finished conduit after the conduit is in..

 

[k0ua]

Almost all underground conduits condense water from the air, even if sealed with monkey chit on each end [ clay like putty ]. We used to drill a small weep hole in rigid conduit run in a low spot to let the water out during installation. Also, some folks put the wire into PVC pipe while they are gluing the 10' sections together... too lazy to suck a mouse/pull cord thru the finished conduit after the conduit is in..

That has been my experience too.. there are two kinds of buried conduits, Those that have water in them and those that will. It may be possible to seal one up air tight, but most that have been in the cool ground have water in them, including ones with both ends inside a building. If any air can get in the conduit, it will have water in it over a period of time. The air has water in it.

 

[JerryK]

Another thing, coax/phone cables/etc. are a bee ach to pull thru conduit. The makeup of their covering sometimes is a pain even with use of pulling compound. Just a normal telephone wire is hard to pull around a couple 90's. We used to put LB's/etc. in every so far if there were a lot of offsets or 90's. Just the nature of the beast. I'd get some fairly strong nylon cord, tie a piece of foam on the end, and try to vacuum the foam [ mouse ] completely thru the pipe. Then, get some good pulling compound, tie the new cable onto the end of the cord, and grease the krap out of it with the pulling compound. Might go thru.. We used Ideal pulling compound, which dries, but tends to stay soapy/waxy feeling even after drying. Lowes sells it...

 

[SPIKER]

if you have too much water a mouse or plastic bag wont pull thru using shop vac. You CAN remove a great deal of water using the shop vac and a air hose , stick air hose or stiff garden hose down conduit and push it thru with shop vac on other end sucking water out as it slides in. 300 feet is good run so might have to work from both ends, and once you got some water out they may pull thru. that all said I bet the others talking about crushed run is correct somewhere (maybe 2 spots heavy truck crushes both sets of wheel paths.)

<mark>

 

[Industrial Toys]

I have seen plenty of crushed 4" corrugated plasic tile or conduit, but never crushed ridged PVC. I have also seen pull cord or wire burn it's way through the corners of that corrugated pipe, if it is a difficult pull.