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Posted By: shortcircuit Water in PVC Conduit - 12/27/08 04:06 AM
I have a problem with water entering a PVC conduit underground at a poorly glued coupling and it is following the pipe right to an LB in a basement and dripping excessively in the basement.

I was looking for ideas for stopping the water without digging the conduit up.

I thought maybe silicone or some sort of expanding waterproof foam.

Any Ideas?

Thanx,

shortcircuit
Posted By: Trumpy Re: Water in PVC Conduit - 12/27/08 04:43 AM
Only way you are going to fix that properly is dig it up and repair the bad joint.
Gluing conduits is 1st year apprentice stuff, especially if they are laid under-ground.
I wouldn't go down the road of sealing the conduit up, it screams of handyman workmanship.
BTW, what size is the PVC conduit?
Posted By: shortcircuit Re: Water in PVC Conduit - 12/27/08 01:49 PM
The conduit is 1.25...

Digging it up is not an option...

The apprentice is an asset to our industry...jus a PIA when they make a mistake...

I may dig it up outside at the foundation and bring it up and through the sill instead of straight into the basement below grade and arrange the conduit do drain outside.

I thought there may be a sealant that would work to keep the water from entering.

shortcircuit
Posted By: Trumpy Re: Water in PVC Conduit - 12/27/08 02:30 PM
With a 32mm conduit, this doesn't sound like a bad joint, leaking that amount of water.
If it was 4 or 6" that might be a different story.
It sounds like there might be a leaking pipe where you came through the wall.

Now don't get me wrong, I'm not taking you to task, shortcircuit, it is easy to blame an apprentice, but at the end of the day, it comes down to the supervisor they have.
If you are going to bury something, make damned sure that all is well BEFORE the trench is back-filled.

Apprentice supervision 101. cool
Posted By: leland Re: Water in PVC Conduit - 12/27/08 02:32 PM
whats on the street end? Pole riser with open conduit? It may be there,then duct seal would work.
Been a lot of water around here lately.I would stay away from "damning" it at the house, reroute may be best.
Posted By: renosteinke Re: Water in PVC Conduit - 12/27/08 07:25 PM
You have to separate what you KNOW from what you THINK.

Our usual glue procedure for PVC conduit does not make for a waterproof joint. We're electricians, not plumbers, so we don't worry about water entry.

This is because water can / does enter the pipe from many other sources ... condensation, boxes, etc.

Pipe should be "arranged to drain." This might involve even putting a weep hole in the side of the pipe at a low spot. Or, replacing that LB with a Tee, for a drain to direct the water whare it won't harm anything.

Mike raised a good point .. are you sure the water is in the pipe, and not just following the pipe through the wall? That is one area that might benefit from some manner of sealing.
Posted By: KJay Re: Water in PVC Conduit - 12/28/08 12:07 AM
I’ve seen this happen with an unsealed conduit in a handhole that was filling with water from rain and melting snow. Duct seal to the rescue?
Posted By: Active 1 Re: Water in PVC Conduit - 12/28/08 02:04 AM
One company I worked for had a rule: don't ever penitrate the foundation below grade. If the pipe was brought up above grade to penitrate the building it would not be an issue.

Posted By: schenimann Re: Water in PVC Conduit - 12/28/08 05:45 AM
We wired a house in a development. While leaving one day I passed a outdoor plug on a short post. We had had lots of rain for several days and was raining now. What caught my eye was the water running out of the cover. The water was running out of the plug like a faucet.

I told the contractor/developer to let me know if they wanted it fixed. It would mean a lot of digging.

Like reno said, we're not plumbers. I do work at good connections though. However, this is why code requires wet location wire in conduit in wet locations. Do they make a wet location gfci outlet? smile
Posted By: Tiger Re: Water in PVC Conduit - 12/28/08 07:43 AM
Originally Posted by shortcircuit

I may dig it up outside at the foundation and bring it up and through the sill instead of straight into the basement below grade and arrange the conduit do drain outside.

I thought there may be a sealant that would work to keep the water from entering.

shortcircuit


Rerouting the conduit seems like the best option to me. The only decent water sealant I know is hydraulic cement & that's not a very good option.
Posted By: shortcircuit Re: Water in PVC Conduit - 12/28/08 01:48 PM
This conduit run is from a dwelling to a detached structure on the same property with the dwelling at a lower grade. There is alot of ground water present on the lot. The conduit is picking up water every time it rains hard.

I did a google search and found this product...

http://www.nettechdi.com/polywater/fst_foam_duct_sealant.htm

This is what I had in mind, just not sure if it will work.

shortcircuit
Posted By: electure Re: Water in PVC Conduit - 12/28/08 03:21 PM
I wouldn't order anything from them..... the reason?

The "kit" seems to be a far cry from sealant

Product Description:
PN5CJ CRLN, 2 DB120 22 1/2D X 18R SWP. 2" 22-1/2" degree x 18" radius elbow.
Your Price: $ 9.150 ea

The "tool" costs $57 for a caulking gun

Product Description
FST-TOOL POLYWATER, APPLICATOR TOOL FOR 2 PART SEALANT KIT, RATCHETING STYLE CAULK GUN
Your Price: $ 57.255 EA


Posted By: Tom Re: Water in PVC Conduit - 12/28/08 04:05 PM
Unless you live in a desert, underground conduits will eventually fill with water due to condensation. The best solution IMO is the previously posted suggestion of bringing all penetrations into the house above grade level.
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