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bobw
03-18-2009, 02:19 PM
Interesting situation I've got to figure out. I have a commercial site where the controller is installed 30 feet below grade. The control wire (multi-strand) exits the building 3 feet below grade. The valve box that the control wire goes to is in an area that has some serious ground moisture issues.

So...here is the problem... the ground water is getting into the control wire between the wires and the sheathing and wicking down into the controller in a small drip.

Any one dealt with this before? Any ideas on solution?

The only thing I have thought of so far is to smear caulking over the cable where we've cut the sheathing back for wire access and stop the water from entering the cable.

I don't want to replace the cable itself because a) I don't want to have to deal with recoring and waterproofing the concrete wall and b) this isn't a fault in the cable per se, more a ground water issue.

Wet_Boots
03-18-2009, 02:57 PM
Simple solution is to add more wire, so the drips can fall off the low point of the wiring, and not drain into the controller. Let someone else deal with the waterproofing.

bobw
03-18-2009, 03:03 PM
The drips aren't on the outside...they are between the strands and the outer sheathing.

Besides...that's a pretty tacky solution :D

DanaMac
03-18-2009, 03:20 PM
How much extra slack is there for the multistrand in the valve box? This may seem weird, but workable if there is enough slack. Unhook the wiring in the manifold, pull wire outside of the box, pull up above ground and install conduit around multistrand, and feed into an above ground junction box. Then run another section of multistrand from the j-box to the valve box and manifold. Wire the sections in j-box together.

Just a thought.

Wet_Boots
03-18-2009, 03:22 PM
Did you install the wiring? It isn't your problem until you stand to make a good profit by its solution.

bobw
03-18-2009, 03:25 PM
Wow..we must be in the depth's of winter...nobody wants to work!

I did indeed install the wiring; I'd like to get my contract holdback paid out, so I am quite motivated to solve the problem

Dana - I can't see an above ground junction box working out. This is right beside a sidewalk in a office building.

DanaMac
03-18-2009, 03:30 PM
Dana - I can't see an above ground junction box working out. This is right beside a sidewalk in a office building.

Well then you're screwed. :laugh:

Try the caulking method then. Create a junction where the wires enter the building. Install in the most waterproof j-box you can get.

Wet_Boots
03-18-2009, 03:32 PM
Then stop exiting foundations below grade, and rewire with an above-grade exit. You could spend forever dinking around with caulks and compression fittings.

If I had to give it my one best shot at a below-grade repair, I put a pipe nipple around the wire, and use hydraulic cement to seal it to the foundation. Then you thread a special cap onto the nipple. A split gland, or single piece of rubber, provides the seal, as you tighten the cap. Electrical supply houses have this stuff.

irritation
03-18-2009, 03:36 PM
Use heat shrink tubing where the wires meet the insulation.

AI Inc
03-18-2009, 03:42 PM
Boots is correct, see if ya can pull more wire thru and create "drip loop" Or replace the wire

Wet_Boots
03-18-2009, 03:52 PM
For service, I'd go drip loop and let them buy a good dehumidifier, but to get paid for an install, I'd go with the electrical compression fittings that they make for waterproof power cord connections.

unit28
03-18-2009, 04:19 PM
what cable do you have? USE USE-2? pump control wire?
other? Most are sensitive to temperature, so yeah, it needs some type of control for the environment.

TRILAWNCARE
03-18-2009, 04:21 PM
Unhook the wiring in the manifold, pull wire outside of the box, pull up above ground and install conduit around multistrand, and feed into an above ground junction box. Then run another section of multistrand from the j-box to the valve box and manifold. Wire the sections in j-box together.

Just a thought.

Dana - I can't see an above ground junction box working out. This is right beside a sidewalk in a office building.


If a J-box is not feasible at the VB. Can you unhook the wire at the controller, pull it out of the foundation and above ground. Install a J-box on the side of the building, that is above grade. Run wire back to controller?

Sprinkus
03-18-2009, 05:06 PM
I'd probably use an epoxy pack or tube like the telephone company uses when they splice underground lines together.

bobw
03-18-2009, 05:52 PM
Then stop exiting foundations below grade, and rewire with an above-grade exit. You could spend forever dinking around with caulks and compression fittings.

If I had to give it my one best shot at a below-grade repair, I put a pipe nipple around the wire, and use hydraulic cement to seal it to the foundation. Then you thread a special cap onto the nipple. A split gland, or single piece of rubber, provides the seal, as you tighten the cap. Electrical supply houses have this stuff.

Boots - I'd love to not exit from below grade, but that wasn't the option I was given. Any exit from the mechanical area is below grade and into landscape. The building sits on an underground parking garage that is bigger than the building and the mech. area is in the garage.

I will look into the electrical compression stuff to see if I can make it work.

I happened to visit this site today to get a feel for the overall condition of things from the winter. I found that due to the ground water three or four valve boxes filled with water, turned to ice and literally blew one end of their lids off (lock bolts held the other ends down). I'm hoping that the valves are ok fully encased in ice.... In general, the condition of the site would make one weep. Their snow removal crews dumped large bobcat loads of snow over ramp walls and destroyed 15' tall spruce trees. Any turf near the sidewalk is covered with gravel from the road way. Their snow crew roto-broomed huge swaths across the sod, destroying a few heads in the progress. A bit depressing to see how much damage can happen in 4 months....

TRILAWNCARE
03-18-2009, 05:59 PM
Boots - I'd love to not exit from below grade, but that wasn't the option I was given. Any exit from the mechanical area is below grade and into landscape. The building sits on an underground parking garage that is bigger than the building and the mech. area is in the garage.

I will look into the electrical compression stuff to see if I can make it work.

I happened to visit this site today to get a feel for the overall condition of things from the winter. I found that due to the ground water three or four valve boxes filled with water, turned to ice and literally blew one end of their lids off (lock bolts held the other ends down). I'm hoping that the valves are ok fully encased in ice.... In general, the condition of the site would make one weep. Their snow removal crews dumped large bobcat loads of snow over ramp walls and destroyed 15' tall spruce trees. Any turf near the sidewalk is covered with gravel from the road way. Their snow crew roto-broomed huge swaths across the sod, destroying a few heads in the progress. A bit depressing to see how much damage can happen in 4 months....


I would be making sure the property manager is aware of the damage caused by others before you to anything. Otherwise you might be fixing the issues for free, to receive the rest of your hold back payment.

Wet_Boots
03-18-2009, 06:04 PM
If you get one of the appropriate electrical connectors, you should be able to connect the dots from there. If it were physically possible to exit above grade, that would be what you would do, and the asthetics of the install take second place to reliability and accepted construction practices. I assume you are familiar with hydraulic cement.

bobw
03-18-2009, 06:08 PM
I would be making sure the property manager is aware of the damage caused by others before you to anything. Otherwise you might be fixing the issues for free, to receive the rest of your hold back payment.

Just walked the site with the building owners. It was a good opportunity for them to see exactly the state of affairs. I'm sure when the get the bill for replacing 3 or 4 large spruce trees on a very steep slope, they'll want to backbill their snow crew...

bobw
03-18-2009, 06:10 PM
If you get one of the appropriate electrical connectors, you should be able to connect the dots from there. If it were physically possible to exit above grade, that would be what you would do, and the asthetics of the install take second place to reliability and accepted construction practices. I assume you are familiar with hydraulic cement.

Boots - I have very limited knowledge of hydraulic cement (i.e. I've heard of it, but that is about it).

There is no way in the world that they were going to core through two floors of office space to bring a wire up, core through the wall, core through a sidewalk and then bring a line to the landscape area. Its not a matter of aesthetics as much as cost and practicality.

Wet_Boots
03-18-2009, 06:17 PM
If you exit below grade, you must learn how to use hydraulic cement, which expands as it sets.

bobw
03-18-2009, 06:29 PM
If you exit below grade, you must learn how to use hydraulic cement, which expands as it sets.

ahhh got it... Luckily, I work on new buildings and the prime contractor usually gets tagged with bringing a line out.. and the mechanical contractor gets to do the take off, meter and backflow prevention.

I'm just the waterboy....

Wet_Boots
03-18-2009, 06:36 PM
Now you can add electrical conduit(s) to the list of items that need to be in place before you start.

djt22
03-18-2009, 08:43 PM
I have seen a few times where guys have took a 3/4 inch line sticking only a few inches in the valve box away from the valve box to act as a drain to keep water from backing up in the valve boxes. Don't know if that may help or not?

TRILAWNCARE
03-18-2009, 10:03 PM
Or you could hire Junior to come over, look it over, shoot it with his lazer,:gunsfirin maybe draw up some plans, skip the permits, trench in some 4in corrugated straight socked pipe using a 12in bucket, because there's no reason for it to be 2ft wide, run one main trunk line down the center and run a couple fingers off of that for the downspouts, perhaps a couple of french drain on oneside and cover it all with 57stone and grade it all out while shooting it again with the his lazer. :gunsfirin

That should fix it........ Hi Junior :laugh:


Of course this all depending on your pocket depth......

(I used his spelling)

bobw
03-18-2009, 11:46 PM
I have seen a few times where guys have took a 3/4 inch line sticking only a few inches in the valve box away from the valve box to act as a drain to keep water from backing up in the valve boxes. Don't know if that may help or not?

There's a foot of washed gravel below the box to help with drainage. The landscape area itself has basin drain plumbed in to help pull water away. The water seems to keep winning. They had to do some serious waterproofing on the sub-basement walls to stop the water from weeping through 12" of concrete.

TRILAWNCARE
03-18-2009, 11:51 PM
There's a foot of washed gravel below the box to help with drainage. The landscape area itself has basin drain plumbed in to help pull water away. The water seems to keep winning. They had to do some serious waterproofing on the sub-basement walls to stop the water from weeping through 12" of concrete.

Too bad your not closer to Texas....... Who was it that said there was a water shortage...:laugh:

Kiril
03-19-2009, 08:23 AM
Now you can add electrical conduit(s) to the list of items that need to be in place before you start.

Well, IMO, that is where you should have started. Just put the wire in conduit and be done with it.