Water in my conduit

solarvic · April 2011

Today I was checking my solar system and see the conduit is full of water. I have top of pole mounted solar panels. The electrician brought the conduit out of the ground straight up the pole about three or 4 feet and left the top of counduit open. He fed the wireing from the panels down into the conduit. Then he filled up and sealed the hole with electricians putty. Guess what happened? The putty came out of the holes and filllec up the conduit with water. I have 4 racks that he did this way. I asked him at the time why he didn,t use a junction box. Said it wasn,t needed and said he did ths before. The inspecter didn,t even complain. So now what will I do. So far everything is working ok, but I am wondering for how long. we used the regular plug in wireing with the MC 3 connectors. I am thinking there is probably 3 or 4 cinections in the water filled conduit. Even if it doesn,t short out I am thinking the water could freeze in the conduit and split it open. What will I do? Is there a way to get the water out?
:grrsolarvic:grr

icarus · April 2011

Re: Water in my conduit

Get a hand vacuum oil pump like this:

http://www.amazon.com/s/?ie=UTF8&keywords=oil+extractor+pump&tag=googhydr-20&index=aps&hvadid=4031845331&ref=pd_sl_159jeci9q4_b

Add tubing as needed, and pump it out. It will suck through a 1/8" tube.

Tony

PS. Personally, I am not sure I would worry about it. All kinds of underground wiring is in vault with water, pipes with water. I suppose a freeze might be an issue, but even it it cracks the conduit what is going to be the real harm?

solarvic · April 2011

Re: Water in my conduit

I called the electrician but just got his answering machine. I have faith that he will call back. When he put in the conduit he had a small pump called Little giant that we used to pump out the ditch so he could lay conduit. Maybe he will let me use it. One good thing is 2 of the mounts are on higher ground than the rest. Maybe if I go to the 2 lowest ones and pump from there THe higher ones will drain. Also do you think an aquarium pump will work? I installed lots of satelite dishes in but I put 2 elbows on the top of the conduit so water couldn.t get in. If I get the water out maybe I can disconnect the panels and put elbows in like I did the satelite dishes I installed.It would have been better if the electrician would have used junction boxes. He did on my other 2 racks and everything is dry with them. If I get the water out I was thinking I might take a vacume cleaner and blow air into the pipe to dry the inside of the conduit. Heck, maybe I can blow out the water with the house vacume. Just thought of that. Do you think that will work ok? Thanks for the idea of using the small pump. Now I don,t fell like it is such a hopeless situation. :Dsolarvic:D

niel · April 2011

Re: Water in my conduit

once you get the water out the original problem remains and i believe your concerns are valid. i would hesitate to advise how to go about it short of putting the elbows on as i'd have to see it to figure this one.

halfcrazy · April 2011

Re: Water in my conduit

I can say as an electrician any conduit I have ever seen in the ground has water in it. I have never worried about it in my 30 years messing with electricity. It is not an issue that i would worry about.

That said here is the real issue You have connections in the conduit?? I would never allow that all connections must be accessible and unbroken wire in the pipe. On the odd occasion the pipe gets dug up by an excavator they make special splice kits with 2-3 layers of heavy duty heat shrink. I would recommend a Junction box on each pole and put the connectors there with unbroken runs of wire in the pipe.

Dave Angelini · April 2011

Re: Water in my conduit

From the array to the pole there should be a junction box with wiring entering at the bottom of the JB and exiting at the bottom. (gravity) It must be liquid tight in/out of the JB. The wire in all conduit out of that box should be wet rated. This becomes more of an issue how long you want to be problem free and not really an inspection issue. We all know about the wide range of inspectors.

solarix · April 2011

Re: Water in my conduit

Open up the other end of the conduit and blow the water out with compressed air.

Peter_V · April 2011

Re: Water in my conduit

solarvic wrote: »

Today I was checking my solar system and see the conduit is full of water. I have top of pole mounted solar panels. The electrician brought the conduit out of the ground straight up the pole about three or 4 feet and left the top of counduit open. He fed the wireing from the panels down into the conduit. Then he filled up and sealed the hole with electricians putty.

No matter what you do you will end up with water in the conduit. Even if you use junction boxes.

Even if you can keep rain out, eventually you will get condensation buildup inside the conduit.

Like halfcrazy said, it happens, don't worry about it.

dwh · April 2011

Re: Water in my conduit

halfcrazy wrote: »

I can say as an electrician any conduit I have ever seen in the ground has water in it. I have never worried about it in my 30 years messing with electricity. It is not an issue that i would worry about.

Agreed.

That said here is the real issue You have connections in the conduit?? I would never allow that all connections must be accessible and unbroken wire in the pipe.

Agreed. Wire underwater no big deal. Connections underwater will corrode.

If there is a low spot in the conduit that you can get to, you can sometimes install a plug in the side to drain the conduit when needed.

Otherwise, air pressure.

solarvic · April 2011

Re: Water in my conduit

My electrician was over today and told me he didn,t think the water in conduit would hurt anything. He sugested after I get the water out to seal it with silicon. Guess I will try that. Am less concerned that I initially was. :Dsolarvic

halfcrazy · April 2011

Re: Water in my conduit

solarvic wrote: »

we used the regular plug in wireing with the MC 3 connectors. I am thinking there is probably 3 or 4 cinections in the water filled conduit. Even if it doesn,t short out I am thinking the water could freeze in the conduit and split it open. What will I do? Is there a way to get the water out?
:grrsolarvic:grr

The damage is done with the connectors setting underwater. I know they are semi water resistant but guarantee they are wet inside and will start to develope some resistance and then it will be down hill from there. Even if you seal it with silicone it will end up with water in it. I am recommending you replace those 3 or 4 wires and get the connectors out of the pipe. I am surprised an Electrician did that in the first place?

Dave Angelini · April 2011

Re: Water in my conduit

Do it right now or do it again later. 100 vdc or less will start the failure for you over time. 300vdc will go pretty quickly with corrosion. Keep the water out in the first place connections or not with DC. AC is much more forgiving here!

Blackcherry04 · April 2011

Re: Water in my conduit

I'd at least carefully drill a couple of " Weep holes " in the bottom of the conduit so it would drain out. I think the ones accepting some water entry were not taking in consideration the connectors being in it. It's a problem waiting to happen. There is a huge difference in Weather Resistance and Water Proof.

icarus · April 2011

Re: Water in my conduit

I think we all agree that connections under water is a no no. On the other hand, drilling a weep hole could conceivably create more problems than it solves. If you have a high winter water table, you could introduce more water than you drain.

If you are worried, pump it out or blow it out with air and try to seal the ends. Like is said before, if there is no joint below grad I personally wouldn't worry about it.

Tony

dwh · April 2011

Re: Water in my conduit

solarvic wrote: »

My electrician was over today and told me he didn,t think the water in conduit would hurt anything. He sugested after I get the water out to seal it with silicon. Guess I will try that. Am less concerned that I initially was. :Dsolarvic

A) Nothing will keep water out of an underground conduit. Silicone or not, it will eventually get wet again.

Connections inside a conduit with water in it WILL CORRODE. Repeat, WILL corrode.

What sort of connections are inside the conduit? Whatever they are, they are probably a code violation.

Weep holes are okay above ground, for instance in the bottom of a bell box, but they won't help underground.

solarvic · April 2011

Re: Water in my conduit

I Am preety sure there is at least 1 connection. I had a different plan than the electrician used to connect the wires. The way I wanted to do it there wouldn,t be any connections in the conduit. The wire is regular MC wire with the mc-3 connections. I think I can disconnect the wire at the combiner box and pull the one wire back thru the other end and get a waterproof splicer and reconnect the ends. Even though I am not an electrician, I think I know more about solar than he did. He never did a solar system before and I had to point out a couple other mistakes he made and had to rectify his mistakes and do some guidance. He is a full time registered electrician and does residential and commercial wireing. :Dsolarvic:D

dwh · April 2011

Re: Water in my conduit

solarvic wrote: »

I think I can disconnect the wire at the combiner box and pull the one wire back thru the other end and get a waterproof splicer and reconnect the ends.

Eh...not optimal, but I guess it's better than an mc3 connector in a pipe full of water.

Just remember to tie something strong to the wire before you pull it out, so you've got something there to pull it back in again.

Of course, if the wires are twisted up inside the conduit, you might not be able to pull out just one - might have to pull out the whole bundle.

solarvic · April 2011

Re: Water in my conduit

It is the ground cable that I think has the connection. The way I was going to connect the series was at each rack. There is 4 different racks with the series string. The electrician connected all the pos and neg to each other and run one wire with 2 50 ft wires to the combiner box with the neg ground from the farthest away rack to the junction all down in the conduit. It is # 10 wire. Maybe I will just try to pull another piece of wire in with the one I am pulling out. I am planing on adding a few more panels any way and probably could use the wire I pull out. I thank everyone for the imput and think this will be my best solution. Won,t worry too much if water is in conduit, just make sure there isn,t any connections. :Dsolarvic:D

dwh · April 2011

Re: Water in my conduit

solarvic wrote: »

Won,t worry too much if water is in conduit, just make sure there isn,t any connections.

Or nicks in the insulation - they'll cause the same problems when they get wet.

mike95490 · April 2011

Re: Water in my conduit

I've used a wet/dry shop vac to get water out of the main utility feed at my old house. It'd fill up again in a week or so. I don't know why. Don't use anything to "blow" it out, you could rupture the pipe, or shoot a slug of water into your charge controller at the other end of the conduit,

tvoss265 · April 2011

Re: Water in my conduit

Electrical conduit is not watertight like plumbing pipe. It is for protection from physical damage. Underground conduit is considered a wet location. As dwh said, nothing will keep the water out. You have to use wet rated wire and no splices in the conduit.

Dave Angelini · April 2011

Re: Water in my conduit

tvoss265 wrote: »

Electrical conduit is not watertight like plumbing pipe. It is for protection from physical damage. Underground conduit is considered a wet location. As dwh said, nothing will keep the water out. You have to use wet rated wire and no splices in the conduit.

Armored liquid tight conduit definately is water tight if you install it properly. It is the best for certain applications.

dwh · April 2011

Re: Water in my conduit

Dave Sparks wrote: »

Armored liquid tight conduit definately is water tight if you install it properly. It is the best for certain applications.

Yea, but not underground. You also have to consider what you're connecting the liquid tight -to-. If running it from say an EMT to a junction box - the liquid tight may be waterproof, but the EMT and the junction box aren't.

I tend to view liquid tight as just rubberized flex. I.e., outdoor flex.

russ · April 2011

Re: Water in my conduit

Just use the right cable and zero splices underground - done in plants around the world all the time.

Underground splices have to be done with the right kit - not a roll of tape. Kind of hard to fit into conduit though - have to push real hard.:grr

I would plan on it seeing water sometime during the life for sure.

solarvic · April 2011

Re: Water in my conduit

In my post where I said I was going to pull a new wire into the conduit as I pulled the old one out must not have been clear. I have another rack or 2 to add to my solar system and plan on reusing the wire I am taking out on it. Not planing on having any more connections in the conduit. Guess Otherwise I am not going to worry about the water in conduit. Can,t do much outside here now is the ground is so watersoaked you can,t walk in it without sinking up to your ankles. Usually by now most farmers have a lot of spring plowing started, especially the Amish. Yhey can,t even get in thier fields to plow with thier horses. Wish we could give Texas our rain. Today is the only day it hasn,t rained for a week and tonight it is suposed to rain everyday for another week. :Dsolarvic:D

Dave Angelini · April 2011

Re: Water in my conduit

The rain does get old when you have had enough. I hope you have good luck with your project. The link below is for what I specify offgrid for gophers and rodents. It just happens to be liquid tite and in sizes from 1/2" and up. The metal interior can be galvanized, stainless, and a few other metasl depending on your application.

http://www.delikon.com
=======================
Flexible, sleek, with increased IP ratings, Liquid-tight flexible metallic conduit (LFMC) is suitable for use in a variety of environments and applications from general purpose wiring in wet or damp locations, to direct burial and in concrete embedment, to raised computer room floors and site lighting jobs.

niel · April 2011

Re: Water in my conduit

i still would not want the water to accumulate in there as a good freeze will do some damage.

vtmaps · February 2012

Re: Water in my conduit

tvoss265 wrote: »

Electrical conduit is not watertight like plumbing pipe. It is for protection from physical damage. Underground conduit is considered a wet location.

An electrician told me about a customer who ran his conduit into his basement through the concrete basement wall. He now has a continuous trickle of water coming into his basement. Estimated head is about 30 ft, but not enough flow for microhydro.

I have discovered that many folks don't know that when glueing conduit together, they should only put the glue on the male end of the conduit. If you put glue on the female side you will push a bit of glue up into the lumen of the conduit, and this glue may form a bit of an obstruction. Putting glue on both male and female would probably make the conduit more watertight, but as tvoss265 pointed out, underground conduit is not meant to be waterproof.
--vtMaps

SolaRevolution · February 2012

Re: Water in my conduit

You can install a NEMA3 j-box or a straight condulet (like an LB but the pipes connect 180 degrees from eachother) and gooseneck type weatherhead on your open conduit. The splices can be made inside the j-box or condulet. A pair of conduit cutters can be used to shorten the pipe with the wire still inside.

Splice can be made reliably water tight if you use the right parts. Check out the splice connectors used for well pump connections. They are barrel type crimp on butt-splice connectors with heatshrink tubing. Use No-lox or similar joint compound and another layer of heavy duty shrink tubing over the whole thing and you have a submersible connection.

I recently had to fix a conduit which which was letting water into a below-grade basement. The pipe ran +/- 150' down a hill from the array and had been leaking badly in the winter making the basement sump pump really work.

Here is a diagram I made to explain it to the guy on the smart end of the shovel:
Attachment not found.

There was already a French drain system (a trench filled with gravel and a perforated drain pipe) running around the up-hill side of the house to drain water away from the foundation. He dug down and exposed the conduit. I cut the pipe and pulled the wire back from the basement. He then set the pipes into an electrical ground pull-box so the one going to the basement was higher than the one comming down the hill. We then sealed the one going to the basement with some spray foam insulation. I stuffed a plastic bag about an inch into the pipe first to prevent the spray foam from going too deeply.

No more leaks.

Water in my conduit

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