Egon
Epic Contributor
Your water source is cracks in the bedrock?
Well Drilled - Results
- Thread starter Pettrix
- Start date
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Your water source is cracks in the bedrock?
Valveman
Platinum Member
Well I stand corrected on one count. I just checked and you can get a 4" shroud in 4.5" casing. But boy is that a tight fit. However, that does solve one of your problems as that will force water past the motor even though the pump is being fed from above. The tight fit of the shroud might make it tricky to pull and set the pump, but the tight fit is a good thing for cooling the motor.
With a 4" shroud on a 3.5" pump, the motor can get adequate cooling with flow as low as 1.2 GPM. Being submerged in water isn't enough to cool the motor. There has to be .5 feet per second flow past the motor. Even if the pump was set in a huge lake or a well that is 10 feet in diameter, the motor could overheat without a shroud. If there is no natural flow past the motor from the lake or big well, you can be pumping nice cool water while the water around the motor is boiling and overheating the motor. For this reason a shroud is actually more important in a large diameter well than a small diameter well. That is only if the pump is set above all perforations. If the pump is set down below any perforations, a shroud is as important as it is when installing the pump in a lake.
A 4" shroud in 4.5" casing is such a tight fit that if you drop something like a pebble the size of a pellet down the well, the pump may never come out of the well. But it will allow for proper motor cooling when setting the pump below the perforations.
However, the shroud will not help if you have cascading water. If I found water from 220' to 500', I would only perforate maybe 40' at the bottom. Then I would gravel pack the annular space between the 6.5" hole and the 4.5" casing. The water from 220' could flow down the outside of the well through the gravel and enter at the bottom perforations without cascading in the well and churning up the water.
If the water from up high is weak and just slowly runs down the side of the casing, it may not cause the churning effect. But if there is a little stream or two pouring in from up top, it can really stir up the water and make the pump lose prime. Or if you do not pump the well hard enough to draw the pumping level down below maybe 400', there should be enough depth of water to stop the churning before the water gets to the pump. If the driller has done this in that area before, he probably knows which way the water enters the well and should be able to make it work.
Valveman
Platinum Member
Well if you want to compare to a VFD system you would need a CSV1A/3gpm and a 44 gallon size tank. The 44 gallon tank would also be needed with the VFD system, so that is a wash. The CSV1A/3gpm would be about $200. I am guessing the larger wire, a single phase motor, and a deluxe motor control box would cost an extra $1000. Then you could deduct the price of the VFD controller, which I am guessing at $1200 to $2000. So because of the long length of large wire there probably isn't much difference in the price of the VFD and CSV system.
But the smaller wire is how they lock you into replacing the VFD controller a time or three. Sure they may warranty it if it quits in the first 5 years. But 5 years and 1 day later the cost will be all yours. And the VFD will shorten the life of the motor. So even though the up front cost will be about the same, over a 20-30 year life, the VFD system can cost many thousands of dollars more than a normal single phase system, which is exactly why people who make their living selling pumps push the VFD system.
Using a couple of 80 gallon tanks and no CSV would cost a bit more, but would probably last as long as the CSV system.
Now don't get me wrong. In spite of the extra cost in the long run, there are many advantages to a VFD system like being able to use smaller wire. It will also deliver constant pressure to the house or sprinklers, and will work with a very small tank the same as a CSV system. It is just that I believe the old saying, "when there are more than one way to accomplish the same job, the simplest way is always the best way".
Valveman
Platinum Member
With a pump that small you have to figure out if the "pressure waxes and waned" because the pump is cycling on and off while using water, or if the pressure just stays low because the pump cannot produce enough flow. If the pump is cycling on and off while showering, simply adding a CSV1A will fix that and give you strong constant pressure to the house. If the pump is not cycling, and the pressure just stays low while showering, then you need a larger pump AND a CSV to give you the volume and constant pressure needed.
OP
Pettrix
Platinum Member
I talked to the pump driller and he said that in 30+ years he has NEVER lost a pump due to a torque arrestor and/or pump shroud in a 4.5" well casing.
He also stated that the wells require the PVC casings because wells can collapse and fill in with sediments. He said the things they do in other states is not the same as here. Geology changes and what works out east doesn't work out west. The PVC casings are a safety measure to prevent collapsing of the well which would require abandoning and drilling another $8k well + $6k well pump. Costing the homeowner $14k in a lost well vs a PVC pipe casing for a few hundred dollars.
He also stated that the wells require the PVC casings because wells can collapse and fill in with sediments. He said the things they do in other states is not the same as here. Geology changes and what works out east doesn't work out west. The PVC casings are a safety measure to prevent collapsing of the well which would require abandoning and drilling another $8k well + $6k well pump. Costing the homeowner $14k in a lost well vs a PVC pipe casing for a few hundred dollars.
OP
Pettrix
Platinum Member
So a non-VFD setup with the two 80-gallon tanks, etc. would be around what? parts & labor $6k?
Qapla
Veteran Member
I fully understand how drilling a well in the SW Desert area of the country is different than it is here - I can still hear the words of the guy who drilled our well over 40 years ago when I asked him why 'that exact spot' he chose from the location where we wanted the well. "Hey, this is Florida - poke a hole anywhere and you are going to hit water," then, as he looked up towards the sky, "This is where I can stand up my truck!" The well was going in a wooded area.
Valveman
Platinum Member
30 years ago the VFD would have cost and extra $10,000, but I would have tried to talk you into it anyway, telling you how cool they are and how much energy they save. Which would have been a lie as I learned later that VFD's do not save energy and do not make pumps last longer. Just like cell phones and calculators, VFD's have gotten a lot cheaper over the years, but they still can't save energy or make pumps last longer.
The cost difference depends on how much your installer charges for pressure tanks and/or a VFD. He probably charges $1000-$1200 a piece for those tanks, which you can get for 500 a piece. He also probably charges $1200-$2000 for a VFD, which you can get for probably $300 from driveswharehouse.com.
But even if there is no difference in up front cost between these two systems, I guarantee you will pay 2-3 times as much over the next 20 years to keep the VFD system working. And even though VFD's do not save energy, they are still cool, as constant pressure is cool anyway you do it.
bigdeano
Platinum Member
You can just put a pressure regulator after the pressure tank like I did. Been working fine for 16 years.
Valveman
Platinum Member
That gives you constant pressure in the house while the well pump is still cycling itself to death. You can get away with that if you don't use much water, like for irrigation. Try that with a heat pump, drip system, or just varied flow irrigation and you would have bought 4 new pumps in 16 years.
The CSV gives you the constant pressure in the house AND keeps the pump from cycling. Saving the pump from all those cycles is what the CSV was designed to do. The fact that is also gives you constant pressure in the house like a regulator is just gravy on top.