7 month old 600' well has silt and sand still?????

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Valveman

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One check valve would have been fine. Two or more check valves can cause water hammer, but I think it will be fine just filling a storage tank. But I do not think the check valves have anything to do with the dirty water.
 

jon chilpigian

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That would probably explain why my pipes hammer hard on this well when it kicks off?
I agree with you. But on the other hand I'm glad that they are at least doing something instead of telling me there's no problem..... lol
 

Valveman

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That would probably explain why my pipes hammer hard on this well when it kicks off?
I agree with you. But on the other hand I'm glad that they are at least doing something instead of telling me there's no problem..... lol

Water hammer on pump shut off is caused by completely different problems than water hammer on pump start. The spring in a spring loaded check valve is suppose to pull the check closed the moment the flow stops moving forward. If the check is closed before the water reverses direction, no water hammer occurs. And if a spring loaded check valve does not close before water reverses direction, it can be because there is enough debris in the check valve to make it drag or close too slowly. Since you have a dirty well, I am pretty sure that is why you hear/see water hammer on pump shut down.

Although you really don't need one on a system that just fills a storage tank, a CSV can help solve water hammer problems on pump stop. This is because the CSV reduces the flow to 1 GPM or 5 GPM (depending on the size of pump and CSV) before the pump shuts off. At 1 or 5 GPM the flow rate is so low that the check valve is in a barely open position when the pump shuts off. So instead of slamming closed from the fully open position, the check valve only has to close from a barely open position when the pump shuts off, which eliminates any possibility of water hammer.

Having two or more check valves in line can cause water hammer on pump start.

If a train were traveling through a tunnel at high speed, and you dropped a huge boulder at the exit of the tunnel, the train would crash into the boulder. The resulting shock wave would be transferred all the way back to the last car in line.

The same way when a pump starts moving water up the pipe and the water hits a closed check valve, the shock wave gets transferred all the way down to the thrust bearing. This is why you don't want more than 1 check valve in line. When 2 or more check valves, one at pump and one at top of well are used, this shock wave can shatter a thrust bearing. If/when the bottom check leaks back just a little or closes slower than the top check, there is no pressure for the pump to start against. This lets the flow below the upper check start moving quickly. When this water crashes into the upper check valve, it is like a train crashing into a boulder. The shock wave bounces back, causes tremendous water hammer, and can shatter the thrust bearing.

With only 1 check valve at the pump, the pump starts against full system pressure and lift. It is even better when it starts against an almost closed CSV as well. The "almost closed" part of the CSV does not block the full system pressure from the pump and lower check. This makes the pump start at 1 GPM or 5 GPM instead of 20 GPM or 100 GPM, depending on the size of the pump and CSV. We already know that the amps drop dramatically on most pumps when pumping against a closed or almost closed valve. This means the pump is not drawing much if any load. So starting the pump against a closed or almost closed valve makes the motor think there is not even a pump attached. This is a mechanical soft start for the motor. This all happens in a fraction of a second. As soon as the pump starts, the CSV starts opening to let more than 1 GPM or 5 GPM through. Then the load on the motor starts to increase smoothly along with the flow rate. As long as there is not another check valve or closed valve for the water to crash into, there is no shock wave, no water hammer, and no damage is done to the thrust bearing.

This is why the longest length of the smallest wire possible makes a good soft starter. Since the pump starts with full system pressure and head against it, the motor doesn't see a load, and starts up really easy and fast. Although that usually doesn't hurt anything, using the smaller wire to "starve" the motor of a little of starting current, makes the mechanical soft start from a CSV even softer.

All pumps will do this regardless of there size. But the damage is more evident and harder on larger pumps the same way cycling is harder on larger pumps.
 

Valveman

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Yes, they can be sometimes. That explains why valveman had troubles with thrust bearings on his old school systems and we don't.
http://franklinaid.com/2012/03/14/why-motors-fail-part-2/

Although I have seen a few thrust bearings shatter from water hammer, this is not the most typical way we see thrust bearings destroyed. Water hammer will shatter the carbon shoes in a thrust bearing. Overheating just melts the carbon shoes down to a nub. Overheating is caused by insufficient flow going past the motor.

Overheating can be because the well is feeding from the top while the thrust bearing is the lowest part of the motor. A flow inducer or shroud over the pump/motor can solve this problem. A shroud forces the water over the motor before it goes into the pump, regardless of where the water comes into the well.

Overheating can also be because the pump is deadheaded. Deadhead can occur if the pump is running against a fully closed valve, a frozen pipe line, or if the pump is too small for the depth of water and just can't get water to the top of the well or shut off the pressure switch.

But most of the thrust bearing failures we see are from cycling the pump on and off. The Kingsbury type thrust bearing does not have any water lubricating between the plate and shoes until the motor is up to 50% of full speed. Although this happens very quickly, every time the pump starts there is a fraction of a second the bearing is running dry. The more times the pump starts, the more time accumulates that the bearing spends running without lubrication.

Also when a pump is cycling on and off, the motor doesn't have time to completely cool down before the pump starts again. The warmer the bearing is when the pump starts, the more damage is caused by the fraction of a second where there is no bearing lubrication.
 

PumpMd

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As long the motor is off for at lest 1min on 4in pumps and 15mins on 6in pumps, it has proper cool down for the motor. The reason why this person is seeing water hammer is because the pump installer didn't install the check valves right, believe me I know because we take that water hammer out of our systems all the time. Your top check valve is going to take the load, so if the check valve is above water level you can tell when it goes bad because you will get air out of your faucets, this let's you know that it needs to be replaced. If your water hammer comes back, that lets you know a check valve is bad and needs to be replaced.

Did the pump installer tell you where they placed their check valves at in the well? I would not let leave the checks valves out on this one because the water draining back will make the motor spin backwards causing damage to the thrust bearing.
 
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Valveman

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For small pumps 1 minute of off time is mandatory. 2 minutes is better because the motor has more time to cool down. But even 2 minutes isn't enough time for the internal parts like the thrust bearing to cool all the way down to water well temp. This is especially true when the pump is cycling on/off continually for long periods of time and accumulating heat with each start and run part of the cycle. Depending on how hot the motor gets and the actual temp of the well water, it could take 30 minutes to an hour of sitting to cool all the internal parts.

Same thing for larger motors, 15 minutes is just the minimum time, but still not enough to cool all the way down. The longer a pump stays off, the cooler it will be on startup.

With a CSV the pump doesn't cycles on and off while you are using water, it only lets the pump shut off when you have finished using water. So there should be plenty of time for the internals of the motor to cool all the way down before water is needed and the pumps starts again.


Yes with multiple check valves the top check takes most of the load. The reason why the bottom check leaks back is because it doesn't have enough of the load or pressure on it to keep it closed well. The bottom check will always work better if it has the entire load or pressure holding it closed, as when there is only one check valve in the system. Air should not get into the lines, no matter where the check valves are located. But when air does get into the lines, it is because of the negative pressure created by the extra check valves up top that are not needed. With the top check holding and the bottom check leaking back, the massive negative pressure below the upper check will draw air in through the threads on the couplings.

When the pump starts, the water at the bottom comes flying up and crashes into the other check valve(s) like a freight train crashing into a boulder on the tracks placed every 200 feet or so. Crash, crash, crash, causes a thump, thump, thump. And for every crash and thump the water hammer causes shock waves that travel all the way to the thrust bearing in the motor, because all the check valves are now open. You won't be having to take water hammer out of your systems all the time, and you won't see the damage water hammer causes, if you only use one check valve at the pump.

Yes if the check valve(s) fail the pump will spin back when shut off, which isn't good. But the check valve is less likely to fail if it is the only one in the system. Also the check valve is less likely to fail if it is just barely open when the pump shuts off, as it would be when using a CSV.

In the cotton fields in my area check valves are rarely used, as we want the lines to drain back when the pump shuts off. You can hear the pump whining as it spins backwards until the water has emptied back in the well. Although this spinning back is not good for thrust bearings, it is less damaging than the shock wave that happens when you have too many check valves in the system.

The picture below shows what can happen when check valve(s) fail and the power is off or the pump doesn't start. The massive negative pressure can suck a tank in like a smashed beer can. Notice the extra blue check valve going into the tank. This extra check valve did not stop the destruction, it more than likely caused the failure.

Tank5.JPG
 

Ballvalve

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Seems like that would have to be a fairly deep well with both the pump check valve and the blue one failed, also with absolutely no use or leaks on all the outlet plumbing. Then, since this is a plain tank, if it had a schrader valve and air maker system, that should have relieved any vacuum[?]

There must have been a specific set of odd circumstances lining up to cause this. Seen this often or has anyone else seen this before? Although this link below makes it very clear the power of vacuum, although these are not pressure tanks from the look of them. From some blogs on the web, guys have used standard well tanks to 27" of mercury vacuum safely. http://sache.org/beacon/files/2007/02/en/read/2007-02-Beacon-s.pdf

on edit: looks like only about 40' of water gives 30" of vacuum in mercury. Seems like we should be seeing a lot more flat tanks.
 
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jon chilpigian

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Here's an update to the update. I have been running straight off the well bypassing the storage for the last 2 weeks and I have noticed a big difference in the quality of water coming out of my faucets.. So this weekend I cleaned out my storage tank of all sand and started to fill the tank from the well. I now have Water flowing as soon as the well pump kicks on. I filled about 2000 gallons into the tank and there is sand and the water is a little murky. But there is not as much sand (at least it seems there isn't) and I can see the all the way to the bottom (barely). It's not clear, but before I couldn't see down past a foot it was so murky. Unfortunately I can tell I'm still going to have to clean my tank once in awhile but it definitely is better than what it was. Any suggestions on where I should go from here? Should I call them out again? Or just add some filters and take is as it is?
 

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Here is a pic of a standpipe or water tower that had the same problem. This happened at a state roadside park during an ice storm. I think the well head and the vent froze and as people were using water in the restrooms the vacuum imploded the tank.
Stand pipe collapse 3.jpg
 

Valveman

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Here's an update to the update. I have been running straight off the well bypassing the storage for the last 2 weeks and I have noticed a big difference in the quality of water coming out of my faucets.. So this weekend I cleaned out my storage tank of all sand and started to fill the tank from the well. I now have Water flowing as soon as the well pump kicks on. I filled about 2000 gallons into the tank and there is sand and the water is a little murky. But there is not as much sand (at least it seems there isn't) and I can see the all the way to the bottom (barely). It's not clear, but before I couldn't see down past a foot it was so murky. Unfortunately I can tell I'm still going to have to clean my tank once in awhile but it definitely is better than what it was. Any suggestions on where I should go from here? Should I call them out again? Or just add some filters and take is as it is?

If 2 weeks of running hard made that much difference, I would just run it another couple of weeks.
 

jon chilpigian

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Hello everyone, It's 4 months and things were a little better but instead of emptying my tank every month, I'm doing it every 2 months. But it gets better. On 6/20/16 it has been exactly 1 year since the well was drilled and now it's tripping the well motor breaker because the amperage is running high. i know motors can go bad but with all the sand and silt problems would think something caused the motor to go bad? So the well company is coming out tomorrow to pull the pump and I'm guessing replacing it and this time I told them I want a Sub K filter installed also. They said no problem and they are charging me $750 just for the separator. No labor to put it on of course. Does that sound fair? And what's your opinion on all these problems? Should I look for or do something while they have the pump out for a second time in one year? Also I had to replace an above ground check valve also due to something in water made the rubber seal swell up and get dislodged from the valve.

Thank you again
Jon
 

jon chilpigian

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Yes, just got home and seen the invoice and it says they replaced the pump, relay box, and put on the sub k filter. I figure I will let it run for a week or so and then let it drain down enough where I can see the bottom. That way I will be able to tell if there is still a lot of sand coming up still.
Does anyone have any other suggestions as far as adding a filter to the house? I was just going to put in a 20 inch big blue to help out with the silt. Still getting a lot of rust-colored water coming up to the house.
 

Reach4

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Yes, just got home and seen the invoice and it says they replaced the pump, relay box, and put on the sub k filter. I figure I will let it run for a week or so and then let it drain down enough where I can see the bottom. That way I will be able to tell if there is still a lot of sand coming up still.
Does anyone have any other suggestions as far as adding a filter to the house? I was just going to put in a 20 inch big blue to help out with the silt. Still getting a lot of rust-colored water coming up to the house.
I like the big blue, or maybe two in series. With 2, you would put a courser filter first followed by a finer filter.

If you have much sediment that is on the larger size, take a look at twist2clean. Really easy to clean out. That would be the first thing after the pressure tank. Then a Big Blue.
 
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