Well pump lost power. How deep should new line be?

DogFather

DogFather

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TLDR: need to run a new power line to my well pump. Being in Greensboro how deep should I bury the new line? What should I use for conduit?

Full story: made coffee this AM, read some posts on the forum them by 11AM no water. Odd.

Checked pump breaker not tripped, flipped a few times anyway. Electrical tester still said no power at pump. WTF?? Followed power line under crawl space to where it exits - all good per tester. So either I got moles that are really ticked or a tree root broke the power line. Crazy but not for this house.

For a temp fix I have a couple cables spliced together inside PVC on top of the lawn which restored water.
 
Metal conduit - 12”
PVC - 18”
direct bury - 24”

At least that's what I recall.

Oh, and conduit needs to terminate a foot or two above ground, so I think you install an outlet on a post at the well, then plug in the pump.
 
Is your existing wire in conduit? If so maybe just pull the bad wire and replace it.

If new, I’d bury 3/4” pvc conduit 18” deep and pull three runs of #10 wire thru it for a 240v well pump, or 4 runs in 1” conduit if 120v.
 
So dig to 18” and bury in conduit or go-to 24 without. I'll start digging and see where we end up. Total distance is a bit under 100' not sure how that will go.

Greatly appreciate the insight.

Anyone want to trade range time for ditch digging? 100 yard+ with several steel targets
 
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Scsmith42 said:
What's the HP on the well pump? Most are less than 2hp so 10GA wire at that length should be fine.
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Honestly I have no idea. The 50” line from breaker to where it exits crawlspace and starts underground was 12/2.

I suppose I could step up to 10/2 as that would match the size currently coming out of the dirt at the pump. Although this calculator says 12/2 is enough for 20 amps over 100”
 
Rent a walk behind trencher for half a day. Your ditch will be dug in a few minutes then all you have to worry with is tamping the dirt back. I’m gonna be renting one soon to run power to my fiancés new building. Might be a month or two. If you’re not in a hurry we could dig yours then
 
You have the distance from the transformer to the house, the distance from the house load center to the well, and the depth of the well pump (or is it a shallow well with the pump at the surface)? All of this factors into the total length, but realistically it's the distance from the load center to the motor.

Pumps tend to have a high current in-rush, so bigger is better in terms of wire.

For a 10A draw and 2% or less voltage drop, 12ga wire is only good for 70' at 120VAC. For a 10A draw at 240VAC, 12ga wire is good for 140'.

If you can find out the HP of the well pump, it will allow you to calculate out the proper wire size. Usually if it is a submersible pump there should be a tag on the well casing that states the pump hp and voltage.
 
Where is Julian? For a fee LeeMajors might dig it for you. He bought my 18” trencher Tuesday. Digging by shovel will be a nightmare. Shane is in Denver.

Edit: I thiught Julian was near charlotte but it’s in Guildford County. Rent a Barreto.
 
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Should I be concerned with what caused a buried electric cable to fail? Home was built in mid 70s so at most the wire is 45 years old which should be no big deal.
 
DogFather said:
Should I be concerned with what caused a buried electric cable to fail? Home was built in mid 70s so at most the wire is 45 years old which should be no big deal.
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I have a fountain pump connected with wire in conduit. It failed before 20 years, and it’s under the road so I’m thinking about pulling the fountain and planting a tree.

Don’t forget to call before you dig. Also, I’d dig a few feet by hand to get away from the other lines near the house and to figure out if you have conduit and at what depth. I can’t imagine pulling up 100’ of 12/2 and wrapping it up in a trencher would be any fun. doing it with a live wire is decidedly not fun.

You should also drop a trace line in the trench 6 or 8” above the new conduit.
 
Burt Gummer said:
True value is who I rent small stuff like that from
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Just tossing this out there in case it helps anybody save a few bucks and/or not rush a job. Looks like TV is open half days on Sat and closed on Sun.

The Sunbelt Rental close to me is closed on Sat & Sun. So you can pick something up after noon on Fri, not return it until noon on Mon, and only get charged for 1 day. Or at least that’s how it worked for the log splitter I rented sometime in the last couple years.
 
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