Pulling PEX water line through a PVC conduit

[Patrick Greenlee]

My 2 inch water line is (about 700 ft long meter to house) has developed a leak after 15 years of leakfree service.It is the kind of pipe that is just slipped together with no glue and depends on an internal a gasket to seal from the pressure in the pipe. Pipe is oversized for its function but it was installed for me for as a trade for use of my land as a lay down area for the contractor that installed our rural water distribution system. One inch PEX would likely be sufficient and 1 1/4 would be a sure thing, I have a bladder type pressure tank at the house to help stabilize the water pressure.

Rather than trenching a new trench I thought I could dig down to and cut through the 2 inch line at both ends, let the line drain (sloping path) and then use a powerful shop vac to blow out remaining water. Then use the shop vac to flow a foam plastic ball through the line to pull a light monofilament line through the 2 inch line. Then use the light mono line to pull a more substantial line (lather rinse repeat) until working way up to a very stout rope. Then repurposing a line puller the electricians use to pull wire bundles through conduits, pull the PEX through the 2 inch PVC. I would use plenty of the lube the electricians use to reduce friction when pulling a large wire bundle to make puling the PEX much easier. I can get the lube in a 5 gal container. There are no sharp bends, just gradual smooth curves in the 2 inch line.

Anybody done this or know anyone who has? Practical/impractical? Is it worth a try? I can always give up and run a new trench but I'm not really keen to trench as I have buried electric supply lines and such to dodge and the weather is starting to get on down the road toward winter.

[Ken Fitzgerald]

Patrick, when I retired, I wanted to replace the galvanized domestic water line coming into our home. My house was built after the one to the east of me and before the one to the west of me. They both had already replaced their galvanized water lines due to the lines rusting out. I checked and found a local irrigation company that installs sprinkler systems. They dug 3 holes, and then used a pneumatic "mole" to punch a hole from one hole to the next and then as it backed out, it pulled a rope. The company was able to pull 1" soft copper line, we drilled a hole through the wall of the basement and a plumber made the final connections at the street and inside the house. In short, they didn't have to ditch anywhere.

I'm not suggesting you run copper line but rather there are other ways of running water lines without ditching.

[Tom Bender]

It sounds very possible, to someone who has not done it. You might need some power to pull it, electricians have winches for this. Maybe need to rent one and the rope. If you have space you might be able to pull it with a vehicle. You will need to get a roll of PEX 700 ft long. You might decide to dig a hole in the middle and make two pulls.

Is your existing water line still clean and smooth. It could have a lot of dirt or sand and it could have barnacles.

Interesting that your name is Greenlee. The Greenlee company makes all the tools for electricians to do this work.

[Stephen Tashiro]

To replace a 30 ft water line in a trench that would end up being under a concrete slab, I installed 2" PVC pipe and then threaded a 1" PEX line through it. As an experiment, I used a shop vac to pull a string through 30 ft of 2 inch PVC and used the thin line to pull a rope through it, but this turned out to be unnecessary. The PEX was pushed through the PVC line in the trench without need of a rope. I advise using "type A" PEX. Type B was too stiff to thread through other pipe.

I don't know whether it's possible to do a camera inspection of your 700 ft line. It would be useful to know whether there are obstructions or shap edges in the line and whether some part of the pipe is collapsing.

[Tom M King]

If the line has only had water in it, it shouldn't be that bad. I've done a lot of such pulling, but don't remember going over 400' through black poly. I always used a vacuum to pull mason's line, with either a rag tied to the end, or taped to a Ping Pong ball. Then the Mason's line was used to do the pulling.

There are pulling tapes that are a lot stronger than mason's line, but braided mason's line is pretty strong. I'm sure Google can find the pulling tape, but I would try the line first before buying the tape.

Though clean "conduit", I've never had any trouble at all. It seems like it always goes easier than I expected it to, and I've never used any kind of pulling lube on pipe.

[Frank Pratt]

Patrick, your plan is absolutely solid. 700' is a very long way to pull, but the key is there are no elbows. But you do not want to try doing it with manual labor. You can rent a tugger from an industrial rental place for well under $100/day. They aren't fast, only a couple of feet/second or so, but they are extremely easy to control. Be sure to secure the rope really well to the PEX.

If you can't find a tugger, or don't want to spend the money, just hook it on to the truck & put 'er in 4-low (low for better control) & be real careful. Another key is to feed the PEX in well from the far end. I don't mean to just make sure it goes in straight, but have enough help that they can actively push it in as it's being pulled from the other end. No need for anyone to overexert, but a little bit of a push from that end helps tremendously.

If you want to get extra fancy, you can also rent a cable feeder that will run the PEX between 2 tires to assist with the pushing.

I've never done a 700' pull before, but have done pulls several hundred feet long in 4" duct with really big wire (750 MCM).

Good luck.

edit: I should add that as you pull the larger line in, it helps to cram as much lube as you can in the pipe & then tie a wad of rag around the knot to pre-lube the pipe. The downside is that it leaves your rope kinda messy. My favorite (I'm a bit of a lube connoisseur) lube is Ideal Yellow 77.

[Bruce Wrenn]

My concern with your choice is "is the lube compatible with the PEX? I would rather use 1" schedule 40 PVC, twenty foot sticks glued together. Due to their ridgidness, you could both push and pull. You can special order 700' lengths of black poly, so no joints in underground conduit.

[Tom M King]

Pipe is Many factors easier than pulling wire! There really is not a comparison.

[Bill Dufour]

I would pull it in 100 foot sections and put in a tee and faucet every 100 feet or so. Do you worry about freezing?
Bill D

[Ole Anderson]

Where are you located? That determines if you can get by with a shallow trench or a deep one to avoid freezing from frost at depth. If shallow, I would suggest that you just rent a trencher and install a new pipe if your soil is not rocky. If your pipe is already more than 2 feet deep, then trenching would likely be by a contractor. You say it slopes down to the street. In 700 feet say that is 15 feet, you loose 6 psi. Adjust as needed. If you run 1" PEX pipe and you are flowing 7 gpm, you will loose another 21 psi. So if you started with 60 psi at the street, you are now down to 33 psi. If you go with 1-1/4" the pressure loss will be only 9 psi, ending up with 45 psi showing you definitely don't want 1" PEX. Too bad your meter isn't at the house, 2" PVC is ideal. BTW, have you checked into the price of 700 feet of 1-1/4" PEX? I think pulling a 1-1/4" pipe in a 2" pipe might be asking for trouble. Think about you would connect a pull line and still keep plenty of clearance.

[Tom M King]

When I pull pipe, or wire (if there is not enough room to loop the wire back), I use a Timber Hitch, and tape. For this long pull of pipe, I'd use 160 psi poly pipe, and put multiple surrounds of the single loop part of the timber hitch, every 6", for about 5'. Once the hitch is neatly in place, I'd cover it with a neatly spiraled wrap of tape. I have always pulled pipe just using masons line, but it might be worth getting pulling tape for this one. The Timber Hitch could still be neatly done with the tape.
https://www.netknots.com/rope_knots/timber-hitch

The pulling end of the pipe would have a number of long V's cut along the length, and the ends of the points bent in to streamline the end, and taped.

As long as the 2" doesn't have any sharp bends, it should go right through there.

I'm not just speculating, or theorizing. I've done similar many times, although never as long as 700'. Pulling wire can be a fight even in short runs, but pipe usually goes right along.

[Bob Grier]

High density polyethylene (HDPE) is commonly used for trenchless installations and for lining old water lines. PEX is made of HDPE but I don't know much about it other than it is used a lot inside new houses.

A couple things that are important with water service is minimal or no joints and that the line is durable and of course certified for potable water. Assuming that 1 1/2" diameter doesn't have too much pressure loss for a 700' service line (calculate pressure loss to confirm size), I would look at HDPE with pressure rating of at least 160 psi or 200 psi. It comes in rolls and the joints can be butt-fused. It can also be joined with bronze stab fittings with double stainless steel clamps on each side of the joint. I wouldn't want to pull pipe joined with stab fittings.

If stab joints are used, I would consider installing access manholes or permanent markers at these locations to help locate and repair future leaks should they occur.

[Patrick Greenlee]

Thanks to all who responded. My location is central Oklahoma about half way between Ada and Shawnee. No nearby fracking.
Sort of rural/remote as in about 25-30 miles to Walmart in 5 different directions.

Meter is located at highest point of water supply line next to the gravel road (section line) that borders our ranch on the west side. I have turned off the water at the meter to avoid paying for leaked water.

As I recall the 2 inch line from the meter to the house is all of the type that is in 20 foot sticks and has one end slightly belled and gasketed. It assembles with a lubricant for the gasket (no glue.) The turns in this line are gentle not sharp. It has worked perfectly for 15 years and then started leaking.

I have a Warn brand PullzAll (hand held 120VAC) winch that will pull 1000 lbs. If that is insufficient I have a 12000 lb winch on the front of my 1 ton Dodge 4X4.

The frost line is about 20 inches deep in centralOklahoma (some sources say 18 inches), the National Weather Service says 20. Since 1960, the Oklahoma State Department of Health has required all water mains to be covered with 30 inches of earth. Not sure the rural water district lines and meters are in compliance. My meter installation was poor. They mounted the meter enclosure too high up and the meter froze cutting of water to out house after a 0F overnight low. I dumped a front end loader load of dirt on top of the meter box and leveled it off even with the lid to the meter enclosure and have had no further freezing problems.

[Tom M King]

Might be cheapest, and certainly easiest, to get someone to find the leak, and either let them fix it, or fix it yourself.

When posters give their location, we can more easily offer better advice.
https://www.americanleakdetection.co...meet-the-team/

[Malcolm McLeod]

I will add one more thing to be considered: what is the tensile strength of the PEX you are going to pull?

It could help to know this limit. If things hang up and you keep pulling, the PEX will part (or hit yield strength and neck down?).

You might get a hanging type scale and put it between the winch/tugger and your anchor point?