Well Drilled - Results

[Pettrix]

So, I would guess that your actual well (the hole in the ground) is 500' deep and that your casing is also 500' deep. I would also think, by your description, that it is the well casing that has the perforations in it. With that in mind, I would then conclude that your drop pipe holding the pump extends down to 480' and that the drop pipe does NOT have perforations.

Correct!

 

[check]

What we call "Rock Wells" are drilled in rock or hard material all the way down. With this kind of well you only have to case at the surface like 50'-100' down. Then the rest of the well is open hole. Some people even set the pump below the casing down in the open hole. But technically you should never put the pump below the casing so the flow goes past the motor and so you don't get the pump stuck under the casing when you try to pull it up Sand or gravel wells would collapse and not stay open. They are cased to the bottom and perfs are used in the water bearing strata on the way down. But the water still needs to come to the pump from below to keep the motor cool. So normally you would set the pump above the highest perforations or use a cooling shroud on the pump/motor.

13 years ago we had our well drilled, and only the first 50 feet or so had pipe. The rest was pretty much solid granite all the way down to 400 feet. The pump is at 385 feet, and the static level is something like 20 feet. Never had a problem since, but I would like to get one of those constant pressure set ups, as I don't like it when the pressure waxes and eaned during a shower or while doing the dishes. Meanwhile, the pipe is 6 inches, and so we have scabs of water, enough to fill up a whole hot tub.

 

[Valveman]

13 years ago we had our well drilled, and only the first 50 feet or so had pipe. The rest was pretty much solid granite all the way down to 400 feet. The pump is at 385 feet, and the static level is something like 20 feet. Never had a problem since, but I would like to get one of those constant pressure set ups, as I don't like it when the pressure waxes and eaned during a shower or while doing the dishes. Meanwhile, the pipe is 6 inches, and so we have scabs of water, enough to fill up a whole hot tub.

I could help you with the constant pressure thing, but I would like to know the horsepower and gpm of the pump if you have it.

 

[check]

I could help you with the constant pressure thing, but I would like to know the horsepower and gpm of the pump if you have it.

5 GPM, 1/2 HP

 

[bigdeano]

13 years ago we had our well drilled, and only the first 50 feet or so had pipe. The rest was pretty much solid granite all the way down to 400 feet. The pump is at 385 feet, and the static level is something like 20 feet. Never had a problem since, but I would like to get one of those constant pressure set ups, as I don't like it when the pressure waxes and eaned during a shower or while doing the dishes. Meanwhile, the pipe is 6 inches, and so we have scabs of water, enough to fill up a whole hot tub.

If you ever have to pull that pump, you probably don't have to put it that deep. Do you know how much the water level draws down when you're pumping? There is a lot of friction resistance in 385' of pipe. You could probably get higher flow if you set it shallower, unless the water level drops way down.

 

[Pettrix]

Some areas do things differently, but that is still pretty weird.

If you set the pump at 480' and the water is coming into the well anywhere above that, the motor will not get the cooling it needs. With perf like that the water could be coming in anywhere up to 280'. You cannot fit a shroud in 4.5" casing, but you could have in 5".

Water is coming in from ALL those areas, over 260 feet of water inflow, water is found 505 feet (bottom of well) up to 220 feet (Static water level). Water is constantly coming into the well casing area from ALL those levels (220-500 feet).

BTW- They will install a pump shroud/torque arrestor.

Why wouldn't the pump get the cooling it needs if it is sitting in 500 gallons of water and constantly submerged with with at all times?

 

[Pettrix]

In 1993 I went back and replaced every VFD I had installed with a CSV, and I have never looked back.

Now having said all of that, the pump system in this thread is not a very good candidate for a CSV. A 2HP, 13 GPM pump with a static water level of 220 will have a backpressure of 192 PSI when using a CSV. And while a 192 PSI backpressure is not a problem for the pump and/or the well pipe and the CSV would work fine, it is a little more backpressure than we like to handle with a CSV.

I would have tested the well, figured out the actual pumping level, and set the appropriate pump so as not to have that much backpressure. When you don稚 know how much or from how deep the well will produce, installing an extra large pump at the deepest setting is the only option. But even then, it is only a 13 GPM pump, so I would have just put in a couple of 80 gallon size pressure tanks and had a system that cost less and was more dependable than a VFD.

Also with 4.5" casing the VFD needs to be set up for the pump to flow a minimum of about 5 GPM required for motor cooling. So you would need a little larger tank, as the pump should be cycling on/off when using less than 5 GPM.

Working between 5 GPM and 13 GPM isn't much variation for a VFD or a CSV, which is another reason I would have just used a couple of tanks and no VFD.

OK, so if it would really "cost less" than a VFD. Quote me an honest quote for installation of a standard NON-VFD pump motor, 480 feet of PVC drop pipe, 6 or 8 gauge wiring, stainless check valves, CSV, and two 80-gallon pressure tanks? Labor + parts

 

[check]

If you ever have to pull that pump, you probably don't have to put it that deep. Do you know how much the water level draws down when you're pumping? There is a lot of friction resistance in 385' of pipe. You could probably get higher flow if you set it shallower, unless the water level drops way down.

Unfortunately, the inflow is only about 1.5 gallons per minute, so we wanted it down as low as possible in order not to run out of water upon heavy usage.

We also have an iron filter, a water softener, two 10 inch "big blue" filters, and a UV light, so we are asking the pump to push through a lot. The pipes are Pex, and unfortunately the plumber only had a half-inch manifold when we put the Pex in. So, we do not have three-quarter inch pipe going into the HWT.

 

[Pettrix]

Unfortunately, the inflow is only about 1.5 gallons per minute, so we wanted it down as low as possible in order not to run out of water upon heavy usage.

We also have an iron filter, a water softener, two 10 inch "big blue" filters, and a UV light, so we are asking the pump to push through a lot. The pipes are Pex, and unfortunately the plumber only had a half-inch manifold when we put the Pex in. So, we do not have three-quarter inch pipe going into the HWT.

You only get 1.5GPM at 385 feet?
That's surprising in Toronto Canada but it's hit and miss with water tables in most areas. I've seen 100GPM in desert areas and 2GPM in areas that area lush with water and vegetation. It's a strange thing

How big is the drop pipe? 1.25 inches?
The longer the pipe and smaller the inner diameter, the more resistance one gets.

 

[check]

You only get 1.5GPM at 385 feet? That's surprising in Toronto Canada but it's hit and miss with water tables in most areas. I've seen 100GPM in desert areas and 2GPM in areas that area lush with water and vegetation. It's a strange thing How big is the drop pipe? 1.25 inches? The longer the pipe and smaller the inner diameter, the more resistance one gets.

The well is at the cottage, which is 2.5 hrs. North of Toronto, up in the Canadian Shield. Drop pipe is 2", and the driller told me you could never predict water flow when you drill. For example, we also had him drill at another cottage we own, about 500 yards away. There, he got 15 gallons per minute at 45 feet!