Sudden Low Pressure from Submersible Pump

[Reach4]

Does the discharge pipe in the air-over tank go all the way to the bottom of the tank?

Air discharge, no.

A 2 HP pump is big. When you pull it, note the waterline on the pump. That can help you select a better size pump for the new one. A 7 to 1o gpm pump is right for most houses.

I have never tried to pull a pump. Getting a pro in for a day, and have water at the end of that day is good.

 

[Liam DuBoise]

Air discharge, no.

I'm not positive that it is a 2-HP pump - that is what's on the labels on the house sub-panel and the control box.

I am now very suspicious of this air-over-water tank; I think maybe it is piped in wrong...? It only makes sense in my head if the discharge to the house is through one of the fittings on the bottom of the tank. I drew a diagram of how it is piped in:

 

[Sponsor]

 

[LLigetfa]

What you show is not a hydro-pneumatic (air over water) tank but rather a contact/settling tank. If there is iron, it gives it time to precipitate. If there is sediment, it gives it time to settle to the bottom where it periodically needs to be purged.

 

[Liam DuBoise]

OK...so I've pulled all of the drop pipe and the pump. The drop pipe turned out to be 1-1/2" galvanized, will the pump set at a depth of 62.0'. The pump is a 2 HP Franklin Electric. The drop pipe had a fair amount of corrosion from about 35'-60'. Did not find any holes in the drop pipe, so am I correct in assuming the pump should be replaced? Is there a way to test it? I would guess that it has been pumping since @ 1997. Many thanks...

 

[Reach4]

so am I correct in assuming the pump should be replaced?

Yes, but not with a 2 HP pump. You could get a 2-wire 1/2 HP pump. Also you should replace the drop pipe. If you have a well person do the replacement, get threaded schedule 80 PVC. If DIY, polyethylene pipe is easier for DIY.

 

[Liam DuBoise]

Yes, but not with a 2 HP pump. You could get a 2-wire 1/2 HP pump. Also you should replace the drop pipe. If you have a well person do the replacement, get threaded schedule 80 PVC. If DIY, polyethylene pipe is easier for DIY.

Thank you... Everything was covered in thick, iron gunk. So you think a 2 HP pump is way too powerful, and 1/2 HP should be good? The depth of the pump was 62', don't know the depth to water, but judging by the look of the drop-pipe, I would say about 35' to the water. The distance to the house is 110', 2-story house. Water is pushed through a settling tank and a two-cylinder softener... Also, one of my neighbors has been talking a lot about flexible drop-pipe; what do you think about this?

 

[Reach4]

Look at this table, and see what you think fits. 1/2 hp 10 gpm seems suitable to me.

Note that what matters is the depth to water.

http://www.pressure-drop.com/Online-Calculator/ can tell you pressure drops at various flows.

Thank you... Everything was covered in thick, iron gunk. So you think a 2 HP pump is way too powerful, and 1/2 HP should be good? The depth of the pump was 62', don't know the depth to water, but judging by the look of the drop-pipe, I would say about 35' to the water. The distance to the house is 110', 2-story house. Water is pushed through a settling tank and a two-cylinder softener... Also, one of my neighbors has been talking a lot about flexible drop-pipe; what do you think about this?

That's what I was referring to when I referred to polyethylene pipe. Think your neighbor might help?

If you do that, you would probably want 160 psi working pressure rating. You would use two worm gear clamps (with the gears on opposite sides) on each of the stainless or brass barbed fittings.

 

[Liam DuBoise]

OK, I get it now... polyethylene pipe like this?
https://www.aquascience.net/endot-industries-submersible-poly-pipe-200psi-1-diameter

My neighbor was talking about this stuff, I think:
http://wellhose.com/

Not likely to get any physical help with this project...

Is the diameter of the drop pipe an issue?

 

[Reach4]

OK, I get it now... polyethylene pipe like this?
https://www.aquascience.net/endot-industries-submersible-poly-pipe-200psi-1-diameter

Yes. HDPE stands for high density polyethelene.

My neighbor was talking about this stuff, I think:
http://wellhose.com/

I know nothing about that.

Is the diameter of the drop pipe an issue?

1 inch SIDR pipe should be up to the task. The fitting on a 7 gpm pump I think is usually 1 inch NPT and 1-1/4 on 10 gpm. Check tho. You can adapt.

The pump will usually have a check valve, but you can add another right above the pump.

 

[Valveman]

At that depth the poly pipe would be fine. I would use 125# or 160# in 1" or 1 1/4" with extra long barb fittings and two hose clamps on each. If you use a lot of water and need 25+ GPM the 2HP is what you need. If the water is for house use only a 1/2HP, 10 GPM pump is all you need.

 

[Liam DuBoise]

Sounds like a plan. Do I need to disinfect the well before installing the new pump?

 

[Reach4]

Sounds like a plan. Do I need to disinfect the well before installing the new pump?

I would sanitize after, but you could get the chlorine strips and pH strips or meter on order. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing write-up. It has bottom feeding wells mainly in mind, but most of the ideas would translate to others.

 

[Liam DuBoise]

I would sanitize after, but you could get the chlorine strips and pH strips or meter on order. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing write-up. It has bottom feeding wells mainly in mind, but most of the ideas would translate to others.

Thanks again! I'll post how it goes with some photos. I have a nearby supply of water from my much deeper irrigation well (5 HP).

 

[LLigetfa]

Do I need to disinfect the well before installing the new pump?

Not unless you already contaminated it. Just wash down the pump, pipe and wire with a bleach solution as you lower it in. Of course wash your hands too.

 

[Liam DuBoise]

Not unless you already contaminated it. Just wash down the pump, pipe and wire with a bleach solution as you lower it in. Of course wash your hands too.

I measured the depth to the water, it is 35'. The depth to the bottom of the well is 65'. The bottom of the pump was set at 63'. Should I set the pump any higher, or ust set it at the same depth?

 

[LLigetfa]

Set it at the same depth.

 

[Liam DuBoise]

Set it at the same depth.

I found this PE pipe locally: https://www.aquascience.net/endot-industries-submersible-poly-pipe-200psi-1-diameter

Think this will be OK? No problem going from the 1-1/4" discharge on the pump to the 1" PE?

 

[Valveman]

200# pipe is hard to work with, but will be fine. Just need to heat the ends to get the barb fittings in.

 

[Liam DuBoise]

So, I'm making progress. The fittings arrived and I got them on the 200# drop pipe, spliced the wires, and ran the pump on recirc in a big bin full of water for a couple of hours. Everything looked good.

New issue: I started lowering the new pump/drop pipe into the well yesterday, and the pump jammed about 8 feet down. Took serious effort (with a fair amount of panic) to pull it back out.

Any suggestions?

Thank you!

 

[Reach4]

New issue: I started lowering the new pump/drop pipe into the well yesterday, and the pump jammed about 8 feet down. Took serious effort (with a fair amount of panic) to pull it back out.

Describe the well casing. Diameter? Depth if you know?

Look down the hole. In the day, direct the sun's light down the well with a mirror. At night, shine a bright light down. Do you see a restriction of some sort? It might be that could be cleaned off.

You should not put a full size 3.9 inch "4 inch" pump down steel casing. There are slimline/trimline 4 inch pumps that are a tad smaller. I have a trimline pump down my 4 inch steel casing. I think I would go to a 3-inch (SQ) pump if I get my pump replaced.

Depending on the restriction, a 3 inch pump may be worth considering despite having bought a new 4 inch pump.