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Hi guys,

I'm in the process of replacing my deep well jet pump with a submersible unit.

Is submersible wire really necessary, or can I get away with using UF-B? I'm not concerned with oil/ gas resistance....

I can't think of a good reason why UF wouldn't work. But it seems like it would be a pain in the butt to install and service and, the last time I checked, it was more expensive than submersible pump cable.

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Thanks Jim,

I'm just a cheapskate. I've got some UF sitting around......

From what I'm seeing on-line, UF seems to run around .50/.60 a foot, while submersible wire is around $1.00 a foot.

PS: The western US Maxitrol rep. who just so happens to live in Tigard sounded interested in teaching a seminar for inspectors. If you're interested, I'll get you his number.

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I have bought a few submersibles and they came pre-wired with over 100 feet of wire attached.

...........maybe it's a regional thing - I've bought a half dozen submersibles(new) over the years and never have seen one with more than a couple of feet of pigtail wire......Greg

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Thanks Jim,

I'm just a cheapskate. I've got some UF sitting around......

From what I'm seeing on-line, UF seems to run around .50/.60 a foot, while submersible wire is around $1.00 a foot.

PS: The western US Maxitrol rep. who just so happens to live in Tigard sounded interested in teaching a seminar for inspectors. If you're interested, I'll get you his number.

Please do. Thanks.

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The fact that I have never seen UF used for this purpose concerns me.

Is UF actually rated to be submerged in water for a long-term basis?

It's listed for use in wet locations, which includes "locations subject to saturation with water."

I think you don't see it used this way because it seems like it would be a pain in the butt to do so.

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I don't know how much the physics gets into this but you can see that normally UF is going to be buried a few feet underground and if said ground is water saturated the max static head you would expect is a few feet. A well, on the other hand, could subject the UF up to two orders of magnitude (100x) the static head on the UF. Ever how much pressure is a factor in driving the water molecules into/through the polymer structure of the UF as opposed to the purpose designed submersible cable is the question that seems relevant to me.

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I don't know how much the physics gets into this but you can see that normally UF is going to be buried a few feet underground and if said ground is water saturated the max static head you would expect is a few feet. A well, on the other hand, could subject the UF up to two orders of magnitude (100x) the static head on the UF. Ever how much pressure is a factor in driving the water molecules into/through the polymer structure of the UF as opposed to the purpose designed submersible cable is the question that seems relevant to me.

Ever seen the wire leads coming off the pump?

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Jim: It looks like your cite clears it up for UF being Ok. Thanks

The connections at the pump is not the condition I was concerned about. I was looking at the possible degradation of the dielectric strength of the insulation (both directly on the wires and any sheathing material) between two (or more) closely spaced conductors at different potentials. That possible degradation being a result of the 100x pressure driving water molecules into the polymer structures of cable not specifically designed for the application. We had to fight that battle decades ago in the communications cable field.

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Just realized the NM and UF have the same insulating material on the wires, only the sheathing material is different, UF having greater UV tolerance.

So what difference does it make whether UF or NM is used for water wells? There's no sunlight inside the well casing.

Marc

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Just realized the NM and UF have the same insulating material on the wires, only the sheathing material is different, UF having greater UV tolerance.

So what difference does it make whether UF or NM is used for water wells? There's no sunlight inside the well casing.

Marc

NM would be poor only because it has paper between the conductors. The paper would absorb water and get nasty.

In UF cable, the sheath completely surrounds the conductors and provides some protection against damage.

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Jim: It looks like your cite clears it up for UF being Ok. Thanks

The connections at the pump is not the condition I was concerned about. I was looking at the possible degradation of the dielectric strength of the insulation (both directly on the wires and any sheathing material) between two (or more) closely spaced conductors at different potentials. That possible degradation being a result of the 100x pressure driving water molecules into the polymer structures of cable not specifically designed for the application. We had to fight that battle decades ago in the communications cable field.

I understand, but the insulation on the wires in UF cables is pretty darned good. Also, while wells are often quite deep, they're usually not that far below the level of the water. A well might be 200 feet deep, but there might only be water in the lower 2 or 3 feet of the casing.

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