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?
Don't think raising pressure will be a problem. Think my max is 60 psi. Not sure you need the bigger tank unless the old one is bad. Also, if your getting some sand or residue, would be a good idea to install a sediment filter.
No. The sand will be far more an issue on pump life if there's enough you can see/feel it...the larger tank may exacerbate that problem slightly by longer run times if it tends to produce more sand as the well is pumped. If, conversely, the well characteristic is such that it cleans up (altho that's fairly unusual I think) w/ time, it could be of little difference. Of course, it all depends on just how much there is.
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.
Interesting... we've got a top-side motor/pump and a submerged jet (80' well), and the moter/pump date from the late '70s, so it's already over
30 years old (the well's newer though - 1986 IIRC - and replaced an earlier 50' well on the property.
The only time we get any debris out of ours is if the water's shut off at the main valve for any length of time - maybe they all do that (it's the first house I've lived in with a private well), or maybe ours is getting toward end of life (I believe 24 years isn't bad at all for a well, and certainly no complaints at 30 for the pump...)
Topside jet pumps are a bit more tolerant of sand in the water and iron buildup than submersibles since submersibles have smaller impellers, tighter spaces and run at higher RPMs.
Don't know about this but I was once told if you can flush the toilet twice and the pump doesn't come on its big enough. This is one of those rules of thumb I picked up somewhere about 30 years ago. With low flush toilets maybe it should be 4.
I agree with dpb without a doubt a larger tank will increase the sand problem. I would add a filter, but still that's ofter the pump so it won't help the pump any.
If it were mine, I'd try to run it dry. Or at least let it run 4 or 5 hours with enough faucets open so that it isn't cycling on and off. Hopefully the outdoor spigots will take care of that. My ex father in law worked most of his life for a water company. When ever a well isn't producing enough, or it has dirt, they try their best to run them dry. What happens is the tiny cracks in the rock were the water comes from sometimes cleans itself free of the sand and sediment. It's sure to get a bunch of sand when you do this, but once it clears up again in a day or two, it may have less sand than now.
If sand/soil/cloudy water is a problem even when it hasn't been used for a day or two, they normally raise the pump 10 or more feet to hopefully keep the sediment below the pump. You could have enough sediment so it has filled in and reached the bottom of the pump, but your well isn't deep enough to raise the pump much so that isn't an option.
Boy, after reading this, don't ever come near my well...
You have no clue of why there's sand in OP's well, nor why it's a problem here (and there's no hope of running this well dry w/o a pump larger than will fit in the hole but one could surely stir up and suck up a whale of a lot of sand and ruin it forever that way... :(
On second thought, I suppose sand spells a lot more trouble than silt from shale or other rock. I do stand by the comments if it had been rock, trying to run it dry. Ever see a very large stream of water running down the road coming from a pump house of a water company? I have many times, and I found out why.
For info: We operated two standard 3 bedroom homes (four people) for some 15 - 20 years with shallow well pumps set at 20 and 40 lbs/ sq.inch. with no problems whatsoever. Although do seem to recall that we did not have a dishwasher at that time. Now (last 25 - 30 years or so) are on municipal water with somewhat higher pressure. No problems when changing over to municipal water using same taps/appliances etc.
That's not a bad though, actually. With that shallow a well, you could probably raise the pump about 1 1/2 to 2 feet and get away with it, if it didn't put it too high to suck enough water. That's likely to be enough to get away from the silt deposits for several yeas. Long term, it's probably going to be neccessary to have the well pumped in a manner that will draw out the sediment; there could be a LOT Of it down there. Depending, it's possible the well is deeper than was measured last due to the sediment building up too. It's not that expensive to do: And is cheaper today than it will be a few years from now.
As long as the pump can keep up with whatever the max demand is, then the only benefit to a larger tank will be less startups. Maybe you will get longer pump life with less startups, but I haven't really seen any actual data that shows that. Also, before moving up from a
20 something tank to a 50, I'd make sure the current one has the proper air charge in it. You can find info on what is should be from the manufacturer's website or use figures for a similar tank if you can't find yours. It's possible the tank has too little air and you can greatly decrease the cycles just by adding air.
Going from 20/40 to 30/50 pressure should be fine and within the capability of the pump. It's actually closer to typical than the 20/40
The way I understand it the longer the pump runs when it cycles the better, a minimum of 2 minutes. The reason is the startup heats the pump, and it cools off as it runs. The way to accomplish this is more storage / pressure tank capacity. As to sand, what you want is a separator like
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that is a little pricey, but you can find them used. They need no cartridge, instead the silt settles out and is flushed with a purge valve
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.
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