Pete C.: Thanks to you and the others for your replies. I checked
into this Lakos sand separator recommended by one of the responders,
it's very affordable at 330.00. But of course it does nothing to save
the impeller from sand abrasion. THe problem is the well guy told
me what the depth of water table is, 60 ft., and he told me what the
drawdown is: 15 ft. while pumping 15 gpm. But what I would like to
know is what total depth of well is, and what depth the pump is at.
Is there a way I drop a line with a small weight attacked and
determine these two things? It's a 4 in. well, and I am thinking if I
drop a weighted line down into it, it would just land on top of the
submersible, since there is probably not much clearance between the
pump and the well casing. I am thinking the well might be 100 ft.
It certainly has to be something more than 75 ft, as the submersible
must be below 75 ft.

I am wondering if I might raise the pump a little...or lower it, and
get into an area where it will be sucking less sand. Perhaps the pump
is at a level where the strata is just very loose sand, or there could
be corrosion holes in the screen of the well casing ringht there.
Do I need to set up an A-Frame and use that wil pulley to pull out
or change position of the pump? THe former owner of the property left
a massive A-frame of 3in pipe on property.

It is funny that no one makes a submersible with a stainless steel
impeller....for just such situations where the well is pumping sand!
At least the well guy said there isn't any such thing available.

I should add that the well water looks perfectly clear, and the water
is sweet. But if you let a cup of water stand for a few hours, you can
see some extremely fine sand particles at bottom.

Yes, I installed a quality whole house filter at the outlet from the
pressure tank. Actually replaced the old/shot one.

We had a power failure the other day, and I ran a 5 KW 115 V generator
to run the fridge and a few other things, but because the well pump is
220V, we had no way to flush the potties. I need to build some
elevated storage. I am thinking about buying some 10ft x 6 in. fence
posts set in sonotubes, to make an elevated support for a 500 gal.
plastic cistern. Hopefully the pump is still in good enough shape to
provide the needed head pressure to fill it. That way if the
electricity fails, I can open a valve below the cistern to keep the
water flowing in the house.

I have an idea to take the well off-grid, by replacing the 220V AC
pump with a 12V one which is solar-powered, and utilizing a bank of
batteries. But PV panels are still pricey, and 12V submersibles are
quite pricey, too, liike 2 or 3 times as much.







On Tue, 16 Mar 2010 10:06:21 -0600, "Pete C."
wrote:


geronimo wrote:

I moved into a rural home which has a water well. I have no info
at all on what type of pump is in the well, or its age. All I do know
is that it is submersible, and it produces 15 GPM. The well guy said
the water level is at 60 ft. and the draw-down was to 75 ft. It is
only a 4in. well. Its producing a little very fine sand. It has a
20/40 pressure switch. THe well guy said it has only a 20 gal.
pressure tank, and he says I should replace it with a 50 gal. tank.

I plan to replace the tank with 50 gal as recommended soon, and I
learned that 20/40 pressure switches can be raised to regulate 30/50
by turning large nut clockwise. It already cycles for only about one
minute each time it comes on, so I know I need to go to a larger tank
before trying to raise the pressure. The only reservation I have about
this is with the pump. Is there any risk to the longevity of the pump
by going to a higher pressure once 50 gal tank is installed?

First off, realize that as you increase the operating pressure the
amount of useable draw-down decreases and pump cycles will be more
frequent. A larger tank will better accommodate higher operating
pressures.

If you are getting sand, be sure to install a decent whole house filter
sump with a basic sediment filter cartridge to keep the sand from
clogging faucet aerators, and damaging faucet and toilet valve seats.
Since the filter normally gets installed downstream of the pressure
tank, be sure there is a drain valve installed at the tank, so you can
drain it now and then to flush out accumulated sand which reduces
useable tank volume.

There isn't much to know about the pump in the well, they're pretty
simple. Depending on the brand, quality, water quality, lightning in the
area, etc. pump life can range from around 7 years to 14 years or more.
Since your well is fairly shallow, it isn't terribly difficult to
replace the pump, I've replaced a couple on similar depth wells.

The operating pressure doesn't have a lot of effect on pump longevity,
water quality such as iron to buildup on the pump screen and sand to
abrade the impellers are more significant factors. Short cycling from
too small a pressure tank and/or too small a hysteresis will also reduce
pump life.

Another note, is that if you have the space available and your existing
pressure tank is in good shape, you do not need to replace it, you can
simply add another tank in parallel. Just be sure to balance the air
charge between them so they work together.