Pressurized water tank bad?

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Good point. I think you can identify a tank with removable bladder by the flange. Some tanks have a diaphram that was inserted before the two halves were welded together.
 
LLigetfa said:
Oh, as for this thread topic, here is a good explanation by valveman of the CSV.
http://www.terrylove.com/forums/showthread.php?40558-Advice-on-Bladder-tank/page2

In that thread he also makes the claim that if you don't have a CSV, you get unacceptable pressure changes when showering, which is absolute nonsense. I've had a number homes on wells. The only one that gave me any issues showering had a 20/40 jet pump, and the real issue turned out to be a restriction in the plumbing, not at the well.

I've yet to see an unbiased authority pronounce the CSV to be a good thing. I have seen a study refuting most of his claims, but that was done by a tank manufacturer, so it's no good either.
 
WhitePine said:
In that thread he also makes the claim that if you don't have a CSV, you get unacceptable pressure changes when showering...
The problem with a subjective term such as unacceptable is that what you find as acceptable, I might not. Keep in mind that unacceptable WRT showering, is a more recent phenomenon with the advent of all these water conserving fixtures mandated by agencies that believe wasting water is a crime. Give me an old fashion shower over most of these modern ones any day, especially when you get into the big box store models. If you want a decent shower these days you need to go to a good specialty plumbing supply and deal in the back room like it was some sort of contraband.

As for consuming more electricity, that has been refuted. A jet pump or submersible is not a positive displacement pump like you might see with a hydraulic log splitter. On a log splitter, holding pressure back would surely make the motor work much harder to the point of stalling. On a jet pump, allowing more water to flow through it makes it work harder. Very different principles that old school pumpmen cannot wrap their mind around.

Holding back flow does increase the pressure between the well and the CSV and the pump needs to be right-sized with the piping. This point is not being very well conveyed, probably since they don't want to talk of the elephant in the room. The CSV never holds back all of the flow.

Wearing out a pump is more likely from frequent starts than constant running.

I grew up on a farm with well water. My father didn't have any mechanical aptitude and so I was the pumpman, mechanic, and electrician, etc.. I've been a DIYer all my life and lived on several well systems in that time.
 
Sorry but I don't buy the refuted part. Refuted by whom? The guy selling the stuff?

I know very well that is not a positive displacement pump. It doesn't matter. The fact is the pump runs longer with the CSV than it would without it. If the pump is running, it is consuming electricity. The excess electrical energy is converted to heat. He claims that by by reducing the number of starts, it saves electricity, because the start windings are not employed as often. But that's not necessarily so. As I recall, the tank company tests (wish I could find them again) found that there was little difference in the average number of starts between a CSV equipped system and a conventional system. That makes sense to me as a long time well user.

Anyway, it seems there has been no independent testing done, which I find telling. If independent testing has been done, and it had determined that there were real merits to the CSV, then I'm sure the company would be pointing long and loud to those test results. Since they aren't, I remain skeptical of the device's merits.
 
There are some old school nay sayers that think a pump draws a given amount of amps and that the same pump throttled back by flow restricting would draw the same or more amps. The fact is that the current a pump draws is roughly proportional to the flow rate, so when the pump is flow rate limited, it actually draws less current than when it's moving more GPM. That was what I meant.

You seem more concerned about the overall cost of operation in terms of electricity consumed. In that regard, no, I don't think a CSV regulated pump uses any less electricity overall but I also don't think it uses much more. IMHO, it is a very small price to pay for constant pressure. The alternative would be to build a 200 foot tall water tower.
 
LLigetfa said:
There are some old school nay sayers that think a pump draws a given amount of amps and that the same pump throttled back by flow restricting would draw the same or more amps. The fact is that the current a pump draws is roughly proportional to the flow rate, so when the pump is flow rate limited, it actually draws less current than when it's moving more GPM. That was what I meant.

You seem more concerned about the overall cost of operation in terms of electricity consumed. In that regard, no, I don't think a CSV regulated pump uses any less electricity overall but I also don't think it uses much more. IMHO, it is a very small price to pay for constant pressure. The alternative would be to build a 200 foot tall water tower.

I would think that pump current is dependent upon both flow rate and head pressure. I put an ampmeter on my pump leads and let it run through a complete cycle. Although the flowrate decreases as the pressure in the the tank builds up the amperage remained the same (as remember, I may need to do the test again).

I'd also be concerned about cooling the pump motor. I've heard that the water flowing past the motor, which is usually mounted below the pump, cools the motor.

Edit: when my well pump does die I plan to install a variable speed unit to address these issues.
 
The two negatives that I see are increased power costs to some degree and increased impeller erosion. The latter could be a big deal if there are a significant amount of suspended solids in the water, especially for pumps with plastic impellers.

On the other hand, I don't see any real benefit either. For average household use, I'm pretty sure the device does not significantly reduce the number of pump starts. In fact, the use of CSV and a small tank, as is now being advocated, may just lead to an increased number of starts.

And as I said earlier, I just don't see any problems with pressure fluctuation on a properly operating and adjusted 30/50 or 40/60 PSI system. I've lived with them for a long time, both with standard and low flow fixtures. We have never had an issue with it.

In most of the places I have lived with a well, all the neighbors were also on wells. I have never heard any of them complain about pressure issues with their wells. Standard systems just plain work.

In agricultural/horticultural applications with heavy watering demands, it would be a different story.
 
I have a friend with the same original problem and putting some air in the well tank valve did the trick.
Mine has also not needed anything in the last 5 years either, however.

Another friend who worked on water wells in his youth suggested a well pump switch with a lever on it that shuts off the pump if pressure gets too low. I added it because it seemed like a reasonable cost improvement. When the power goes off, however, and the water has been run during the outage, the switch has to be reset.

After reading about some water treatment threads on here in the past, I can only say that I am greatful that my water is good enough that I don't have to become knowledgable about all the technology required for reasonable quantity and quality drinking water.
 
Ja, +1 on the low pressure shut-off. Worth the minor pain to reset it and save from burning up the pump. These switches with the low shut-off need to be tested from time to time. I was surprised to find out mine stopped working after my wife drained the tank during a power outage and when the power came back on, the pump started. There is space for the diaphragm to move and this space can fill with rust and mineral over time. That can also cause the pressure switch to not come on at the usual preset. I finally change mine out when it would drop to 18 PSI before coming on. A new switch with low shut-off was less than $20 at Menards.

Also don't trust what the pressure gauge says, especially if it's old. It could be built up with the same rust and minerals. I now have a second gauge on the top of my bladderless air volume tank and I also installed a shraeder valve so I can compare the pressure with a tire gauge.
 
I drained the system and added air to 18 psi (2 psi below the cut in) It seems to be holding pressure. Closed the Faucets and turned it back on. Ran brown water for a bit but has cleared up. I figured I stirred up some sediment when I charged it. So now with the cold water wide open to the tub and kitchen sink I went back down to monitor the gauge. The cut in pressure now reads 25 psi and 40 off. It is taking about 3 to 4 min to get back down to 25psi. How long should it take? Also I rechecked the air valve and now reads 35 psi on the tire gauge. I had it set to 18 when the tank was drained. Is that normal or do I let air out now.

Thanks, Steve
 
Don't worry about how long it takes to drop. That will depend on how many taps you have open and what their total flow is. Instead, you should worry about how long it takes to bring the pressure up from the low to the high. It should take at least one minute. The pump needs to run a little while to cool the start winding. If it takes less than a minute, you need a bigger tank.

To measure the pump time, open a faucet until the pump kicks on. Immediately close the faucet and time the pump. One minute or longer is the rule.

The pressure you are reading is normal. You can only measure the tank pre-charge when the system is off and the tank is drained.
 
Thanks a bunch the posts have been very educational as I had none in this subject. I guess time will tell if the charge holds. It is a Duracell DP-82 tank and seems to me quite large. Does the 82 represent gallons? In the double wide I used to have before I bought my house was a little blue tank I assume would be 14 gallons. The place had 2 full baths, 2 sinks and great pressure with that little tank. In this house we have 1 full bath and kitchen sink. So why the good pressure with the smaller tank with more potential faucets running in the old place to less pressure with a larger tank and less possible faucets to use. I forgot to mention washers for both places. Also I was trying to locate that nut to turn to increase the cut in pressure but not sure what that is. There is nothing looking like a nut but there are 2 round "thingy's" one on the vertical pipe and one right under a spicket on the horizontal pipe.
 
The pressure switch adjustment will vary by brand and model. My Square D has two springs. One is the differential and the other the high cutout.
 
I'm not familiar with that brand, so I don't know what the 82 means. Typically, bladder tanks are rated as equivalents to larger conventional tanks. A "36" gallon bladder tank, for example, will be smaller than a conventional 36 gallon tank. while providing equivalent performance. They are also simpler to hook up, since they don't become water logged or require an air control device.
 
Ahahh the nut and spring is under the switch cover like was mentioned previously. Thanks, Found em. As of this am pressure was constant and only felt the pump come on once during my shower. Knowing my luck I should just leave well enough alone but I always crave more pressure. I have showered in places before and when getting out thought to my self " wow that was a great shower I feel so refreshed" I want that to be my shower.

Again thanks for your help and advise :)

Steve
 
It might be flow too. Newer fixtures are low flow by law (I think).
I have the same feeling about the shower at my relatively new place.
On the other hand, maybe it also puts less strain on the well, which in my case is 450' deep and had been hydro-fracted.
 
velvetfoot said:
It might be flow too. Newer fixtures are low flow by law (I think).
I have the same feeling about the shower at my relatively new place.
On the other hand, maybe it also puts less strain on the well, which in my case is 450' deep and had been hydro-fracted.

I have heard ;-) that low flow shower heads sometimes have a reflow problem. :)

It's probably just a rumor, though. :eek:hh:
 
Sounds like you have got some of this under control. but, for what it is worth. Your not really suppose to have to "recharge" your pressure tank. It is Ok to do, but it means you to have a leak. Usually means you have a pin hole in the bladder. You will be able to use the tank like this until the bladders gets waterlogged (Water on top of the bladder where it doesn't belong). Or it means your loosing air through a valve somewhere (usually the sniffter valve <-- haha, I can't remeber the name. might be chaffer valve. Air tube type valve anyway.)

A tank with a bladder is a pressure tank. No bladder is just a holding tank, which gives you more storage. Takes longer for the pressure to drop, longer to build up. How long depends on your pumps ability to pump and you wells ability to produce.

You can increase the pressure consistancy at you fixtures by increasing the diameter on the supply lines (depending on what is there). 3/4" pipe carries twice as much water as 1/2", 1/2" alomost twice as much as 3/8". Over pressurizing the systems with your pressure switch will obviously create more prussure but can create problems if your not carefull. If you not sure of the age of your plumbing you may have older valves or other weak spots that will fail quicker with higher pressure. (Think old washing machine hoses).
 
murph said:
A tank with a bladder is a pressure tank. No bladder is just a holding tank, which gives you more storage. Takes longer for the pressure to drop, longer to build up. How long depends on your pumps ability to pump and you wells ability to produce.

That is not correct. Closed tanks, be they bladder type, diaphragm type, or conventional are all pressure tanks. The fact that they are designed to hold water at a pressure above atmospheric makes them pressure tanks (or vessels) by definition. All pressure tanks store water to some degree.

A water storage tank, is open to the atmosphere (vented) and requires at a minimum a downstream pump.
 
A new tank was definately the right move here. I had the same issue about five years ago and a new tank solved the problem. A plumber told me to use a 40/60 pressure switch.
 
WhitePine said:
A water storage tank, is open to the atmosphere (vented) and requires at a minimum a downstream pump.
Not to put too fine a point on it, but if said tank is elevated enough, no pump is required. A 100 foot tall water tower should give you around 40 PSI AGL.
 
LLigetfa said:
WhitePine said:
A water storage tank, is open to the atmosphere (vented) and requires at a minimum a downstream pump.
Not to put too fine a point on it, but if said tank is elevated enough, no pump is required. A 100 foot tall water tower should give you around 40 PSI AGL.

I have friends who use nothing but elevation to get their water pressure. Their tank is high up a hillside, fed by a spring up there. Free water and free water pressure is a good deal.
 
So to get back to the original post... Should the tank be replaced or does it have life left to "milk"? Since re-charging the bladder over a week ago the pressure remains constant and showers are much more enjoyable.( by that I mean a more constant pressure) I haven't had the chance to try and adjust the pressure yet to like 30/50. When thinking about it everything that takes air eventually needs it..tires etc.. is this no different?
 
You could just watch it and see what happens. No sense spending money if you don't need to, but.........

Be sure to check the pump's run time when you change the pressures. Might not be a bad idea to do it now. That alone could dictate a new, larger tank. There is no guarantee that the system was installed with a correctly sized tank in the first place.
 
“My water pump is “short cycling†from what I have read, the bladder usually goes bad rather to add air. Would you agree?â€
“Short cycling isn’t just an annoyance, but will reduce the pump’s longevity if it isn’t taken care of.â€
“Running less than one minute will not allow the start windings to cool properly.â€
“Wearing out a pump is more likely from frequent starts than constant running.â€
“Your not really suppose to have to “recharge†your pressure tank. It is Ok to do, but it means you to have a leak. Usually means you have a pin hole in the bladder.â€
Cycling causes nearly every problem with conventional pressure tank systems. Cycling wears out your pump, motor, pressure switch, start capacitors, starting relay, and check valves. Cycling even destroys the bladder in the pressure tank, as it goes up and down with each cycle, and breaks like bending a wire back and forth.

“only felt the pump come on once during my shower…. but I always crave more pressure…. I have showered in places before and when getting out thought to my self †wow that was a great shower I feel so refreshed†I want that to be my shower.â€
“My in-laws shower has so much pressure. It is almost worth the drive to NJ just to use it!â€
Anyone with a pump system can have better pressure than “city waterâ€. You lines could be too small, there could be restrictions, or just a bad showerhead. But if you can tell when your pump comes on or goes off because of the change in shower pressure, then your pump cycling on and off is the main reason you have low shower pressure.

“he also makes the claim that if you don’t have a CSV, you get unacceptable pressure changes when showering, which is absolute nonsense.†“Standard systems just plain work.â€
Sure they work. But, you have simply learned to live with varying pressure in your shower, because you haven’t experienced a better way. This is like thinking your own bed is the most comfortable in the world, then lying on a new mattress and having that “OMG!!!†feeling. Once you experience “constant pressure†you will never go back.

“I’d also be concerned about cooling the pump motor.â€
“The two negatives that I see are increased power costs to some degree and increased impeller erosion.â€
“For average household use, I’m pretty sure the device does not significantly reduce the number of pump starts.â€
CSV will not cause “impeller erosionâ€, “overheat the motorâ€, and it “significantly reduces the number of pump startsâ€. “I’d be concernedâ€, “negatives that I seeâ€, and “I’m pretty sureâ€, means your just guessing. Which is how these myths, rumors, or untruths get started.

“Be sure to check the pump’s run time when you change the pressures. That alone could dictate a new, larger tank. There is no guarantee that the system was installed with a correctly sized tank in the first place.â€
As Lligetfa said, a larger tank will only….
“stretch out the time factor. The agony of low pressure is just extended. A CSV on the other hand, will give you much more time at the higher end with true constant (steady) pressure and less time at the lower end. The smaller the tank, the less time you suffer through low pressure.â€


You said…â€The fact is the pump runs longer with the CSV than it would without it.†Then you said… “The pump needs to run a little while to cool the start winding. If it takes less than a minute, you need a bigger tank.â€
Wait a minute! So the CSV causing extended run time is a good thing? Instead of cycling on and off every minute or two, the CSV will keep the pump running as long as the shower or any faucet is open. Then it still has to refill or top off the pressure tank at 1 GPM before the pump shuts off. Why would you need a larger tank? To confuse you even more, the reduced amps caused by the CSV, means the motor is de-rated, not making as much heat, and doesn’t need as much time or flow to cool.

“Holding back flow does increase the pressure between the well and the CSV and the pump needs to be right-sized with the piping. This point is not being very well conveyed, probably since they don’t want to talk of the elephant in the room. The CSV never holds back all of the flow.â€
No “elephant in the roomâ€. This is exactly what makes a CSV work so well. Our entire web page is dedicated to this subject. We give maximum inlet pressures and differential pressures for each valve model. We have countless articles explaining how to figure backpressure, that it makes the pump work easier, draw fewer amps, and reduces the amp draw. There is even an animation with a back pressure gauge. I don’t know how to be more clear.
 
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