CSV Questions

I've been reading up on Cycles Stop Valves and have a few questions.

1. The CSV is a trademark/name for a constant pressure valve? Yes/No?

2. ValveMan has a financial interest in selling CSVs? Yes/No? I'm not saying this is bad, if true. I just want to be informed.

3. With a 30/50 PSI pressure switch, would you use a 40 PSI CSV, or would it be better to use a 50 PSI CSV and raise the cutoff pressure a couple of pounds?

4. I have read the statements at cyclestopvalves.com regarding pump life. While I understand why starts are bad for a pump and reducing them will extend a pump's life, it is not clear to me why the longer run time doesn't erode the impeller faster and wear out the bearings earlier, thus partially or wholly negating the reduced number of starts. Why isn't this discussed?

Anyone care to comment?

RedClay said:

I've been reading up on Cycles Stop Valves and have a few questions.

1. The CSV is a trademark/name for a constant pressure valve? Yes/No?

2. ValveMan has a financial interest in selling CSVs? Yes/No? I'm not saying this is bad, if true. I just want to be informed.

3. With a 30/50 PSI pressure switch, would you use a 40 PSI CSV, or would it be better to use a 50 PSI CSV and raise the cutoff pressure a couple of pounds?

4. I have read the statements at cyclestopvalves.com regarding pump life. While I understand why starts are bad for a pump and reducing them will extend a pump's life, it is not clear to me why the longer run time doesn't erode the impeller faster and wear out the bearings earlier, thus partially or wholly negating the reduced number of starts. Why isn't this discussed?

Anyone care to comment?

Click to expand...

1. yes.

2. He is the inventor and manufacturer. The CSV web site is his too. The CSV has been around for about 20 years IIRC and again IIRC, it has been sold all over the world.

3. If 30/50 psi is good for your household, and you aren't going to remodel adding more water use, use the 40. Otherwise go with the 50 and adjust the air pressure in the tank to 39-38 psi and the switch to 40/60.

4. Water pumps are made for continuous running and starts are much harder on a pump than running for X minutes until you shut off the water or reduce the flow to less than 1 gpm. Do you have something in your water that would eat impellers etc.? If so it will eat them no matter if the pump cycles much more frequently without a CSV or much less frequently with one but the pump runs longer.

I see the main advantage of the CSV is in systems that have periods where the pump should run constantly, but also have times when you want to use a pressure tank.

For example: A house with a large sprinkler system.
The CSV allows the pump to run continuously when the sprinkler is running while still allowing the pump to turn off when little or no water is needed.

Theoretically a screw type pump and a VFD(variable frequency drive) would be more efficient, but currently available systems are not as efficient. VFD's are also still a lot more expensive than the CSV.

*grins* Give it 5 years. It's just a matter of time and VFD's will be back*evil laugh*

>4. I have read the statements at cyclestopvalves.com regarding pump life

That is a hard question, but I don't see anyone arguing that it will reduce pump life in terms of gallons used.

Using a CSV with a REALLY small tank COULD shorten the life of the pump.

The life expectancy is likely to increase as long as you use the same size tank since the pump would reduce the number of cycles while only running a tiny amount more.

Note: The "tiny" tank problem is really bad in the so called "tankless" systems.

Edit:
Disclosure statement: I do some work in the power electronics area and have an interest in promoting power electronics, VFD's, Electric cars, UPS's, Power Inverters, and most electronics.

Thanks for the info, but I still have a question about pump longevity. According to http://www.cyclestopvalves.com/geninfo_3.html, current production pumps are built to fail. Here's the relevant quote:

"Since the 70's, companies have continually shortened the length of motors and replaced lifetime ball bearings with short-lived bushings. Pumps have been changed from having heavy duty brass impellers to all plastic. These changes were not made for the better but, rather to shorten the expected life of pumps and motors."

So why would longer run times cause pumps with "short lived bushings" and "plastic impellers" to last longer? It seems completely counter intuitive.

When considering the life of a pump you might want to consider the manufacturer's recommended minimum flow. Any control device that throttles the flow will cause the pump to operate at point outside the recommended operating range of the pump.

Throttling the pump below the rated/recommended range with a control valve reduces the efficiency and increases the pressure at the discharge of the pump and in the pipes between the pump and the valve. In some cases the peak pressure is greater than the rating of pipe used in the well.

Here are some typical values for the Goulds GS series submersible pumps.
It takes a little less power to run the pump at low flows but the efficiency is much lower. Efficiency will be near 10% or less for pumps operating at 1 GPM.

5 GPM pumps. Recommended range 1.2 to 7.5 GPM
HP / PSI at 1 GPM
0.5 /169
0.75/222
1.0/277
1.5/365

7 GPM pumps. Recommended range 1.5 to 10 GPM
HP / PSI at 1 GPM
0.5 /130
0.75/169
1.0/221
1.5/294

10 GPM pumps. Recommended range 3 to 16 GPM
HP / PSI at 1 GPM
0.5 /91
0.75/130
1.0/160
1.5/234

Pumps are made in two parts; the motor, and the wet end.

Cycling (on/off) eventually kills the motor because there are just so many cycles before they die.

The wet end could all but care less how many times they start or stop. Or how many gpm they are producing. BTW, it is much easier to replace the motor of a submersible pump than replace the wet end of the same pump. And the motor usually costs more.

Gould's doesn't make motors, although they are involved in motors since Franklin and wet end manufacturers had a falling out, and they decided to not supply them with motors (the oldest and most widely used pump motor ever) and bought a pump manufacturer (Jacuzzi IIRC) for their own pump manufacturing.

Yes, not every house or business should go with a CSV, but those with the need are much better off with one than not; assuming they don't like the idea of their pump failing prematurely (even if the wet end has bushings). And most of the nay sayers never have seen a CSV in operation and usually are the only ones against them. And as we see, most of the nay sayers are engineers looking at pieces of paper produced by others than the constant pressure devices; and some are competitors with variable speed pumps etc.. It's kinda like all the scientists telling us all life required sunlight so the ocean floors were devoid of life, until they were proved wrong just 25-30 years ago.

I would just like to add that the CSV does work and is the right choice for applications where the flow rate is high and predictable. (like sprinkler systems)

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The only scenario that i can think of where a CSV might shorten the life of the pump is one where there is small continuous water use that is lower than the CSV's minimum flow rate. This would result in the pump running longer with the same number of on/off cycles.
The best option in this scenario would be a larger tank.

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Me and ValveMan may argue about VFD(variable frequency drive) vs the CSV, but right now the CSV is still better unless you are up in the 100Hp range.

I've worked on some transistor based city sewer lift station VFD's and back then the units were huge. Now days they are the size of a desktop PC.

Prediction: The trend is continuing in hybrid and electric cars and eventually it will be cheaper to combine a hockey puck sized VFD with a small High frequency AC motor to create a VFD/pump unit that would be entirely down the well. It will take 20 years for high frequency ceramic motors and tiny VFD's to be on the market.

So the cheapest option for now is the CSV.

PS: I may be a "engineering type", but I have real world experience complete with a very educational set of failures.

CSV, try it you'll like it!

Most of the nay sayers never have seen a CSV in operation and usually are the only ones against them.

Almost always use a CSV if you want to prevent the pump from cycling and give you a constant pressure. The women love constant pressure!

Porky

Hi RedClay
I would say that the few small valves that are sold because of forum questions, in no way justifies the time I spend answering questions. I already sell tens of thousands of these valves every year to pump installers, irrigation specialist, municipalities, green houses, tree farms, feed lots, car washes, and the list goes on. I only answer questions on forums to straighten out the misconceptions that people have about pumps, valves, and VFD's.

Pumps might as well be magic to some people, as they do not understand how they work. Even people who think they understand pumps, have incorrect conceptions about how they react to being throttled with a valve or slowed down with a VFD.

It also amazes me that very few people understand that pumps, as well as most other things, are built with "planned obsolescence" in mind. Less durable materials, including bearings, are now being used. The motors are much shorter and have less "meat" in them, than in the old days. The target design life for a pump is an average of 7 years. They are still designed for continuous duty, and will last longer if run that way, than if cycled on and off. The bearings and bushings are basically frictionless when up and running. A lot of things happen on start up to cause friction and wear, even with VFD's or soft starts. So the less number of times a pump starts, the longer it will last.

Many people, including pump engineers, will spout off about "minimum recommended flow rates". These are only "recommended", and not law. Pump men who have had to deal with low producing wells all their life, know that pumps will last a long time when throttled back to the ½ or 1 GPM that the well will produce. Especially when compared to cycling the pump on and off to extract ½ or 1 GPM from a well. It has been my experience that a pump throttled back to 1 GPM and running 24/7, will outlast a pump in a high producing well that cycles on demand, by about three times to one.

I actually started with VFD controls about 20 years ago. And yes back then they cost $5,000 and were the size of a small car. Now you can get one for a couple hundred bucks and they are only the size of a shoe box. It makes sense to most people that slowing the RPM of a pump would use less energy. It is "counter intuitive" and therefore does not make sense to most people, that choking a pump back with a valve will reduce the power consumption as much a varying the speed. This is one thing that takes someone with real pump experience to understand. Anyone who talks about valves "burning energy" and a VFD being more efficient, does not truly understand pumps. We discovered almost 20 years ago, that the valves we were using as a bypass when the VFD's failed, were just as efficient and much more reliable than the VFD.

We started out many years ago, replacing VFD's with valves, and we still replace VFD's everyday. Even though VFD's are smaller and cheaper than years ago, there are still many problems with VFD's that mother nature won't let anyone fix. Harmonics, voltage spikes, resonance vibration, low flow rates, and many other problems exist with VFD's that are not present with Valve control. Our best customers are ones who have already been through the VFD phase and like the "constant pressure" but, hated the complications and unreliable water supply from a VFD.

I predict that Bill Arden is right, that in a short time the VFD will be incorporated into the motor itself, so we don't have any choice of purchasing it or not. This is just one more way of forcing "planned obsolescence" on the public. Then we will be forced to replace our pumps as often as we replace our computers. We will be replacing our pumps every 5 to 7 years as the manufacturer likes, and the public will not even remember that pumps should last 30 years. Gone are the days of one pump system lasting multiple generations. It is impossible to save enough energy to pay for 5 or 6 pump systems, compared to having one pump system last 30 years. Of course manufactures want you to think they are doing things to save energy, when in reality, they are doing things to keep your cash flowing into their pocketbooks.

VFD's have been around for more than 30 years. During this time they have been saying that in the next few years all the bugs will be worked out. I don't think they will ever be able to get rid of all the VFD bugs. There will just come a time when we accept it, and start thinking that shelling out the bucks to replace a pump system every few years is normal. With enough money spent on marketing, we as sheep, won't even turn our heads while being led to slaughter.

valveman said:

"planned obsolescence"

Click to expand...

The last I head the transistor based VFD i worked on is still pumping city sewage. So the problem is not necessary the technology, but the manufactures and customers not demanding a 15 year manufacturer warranty.

(begin rant)
I also get annoyed at that "planned obsolescence" has been designed into everything. I bought thee flat panel monitors a little over a year ago. Two of them died just after the warranty and WorstBuy said they weren't even worth sending in to be repaired. I took them apart and found two bad capacitors in one(samsung) and two bad transistors in the other(dell). I repaired both of them in less than 6 hours(not inducing waiting for parts to arrive) and this makes me wonder why... why... why does the world buy into this whole throw-away lifestyle.
(end rant)

Hi Bill
I am afraid that VFD's are also being made with "planned obsolescence" in mind. Those old transistor based systems are lasting longer than the manufacturer wants them too. So now, even Allen Bradley, who I think makes one of the best VFD's, has redesigned their units to cost less but, not last as long. For instance, they use to have a power pack for each of the three phases. Now they are making a single power pack to work for all three phases. This cuts cost and makes them more competitive with the millions of other companies that are doing the same thing. Although, it increases heat, decreases dependability, and makes these systems not last as long. We are told to plug in 17 years as the average life of a VFD, which would make these systems actually save some money and energy. However, from one company who sells VFD's, they say the average life is less than 8 years, and does not last long enough for a pay off.

http://www.powerqualityanddrives.com/payback_analysis_vfd/

I hear from other people who work on VFD's, that the actually life expectancy is really only 3 to 4 years. This means even though they have become cheaper, that you will spend more money on VFD equipment than you will ever save in energy.

(Now my rant)
"Planned obsolescence" is a closely guarded secret in nearly all corporations. It is discussed at the highest level and hidden from everybody at the lower levels. It is adamantly denied if you ask about it but, it is built into nearly everything we purchase. To further confuse anyone who might overhear, it is usually referred to as a "fluid system". This has nothing to do with water. It simply means that the products are flowing out, and the cash is flowing in, "fluidly".

This can be a real "tar baby" once you buy into it. Companies want a repeat sell so they put very little quality into their products. We believe quality is not longer attainable, so we shop for the lowest price. The lowest price requires companies to put even less quality into their products so, the vicious circle continues. It is all being done so slyly, that most people do not even realize it is happening, and will brand you a Domesday sayer if you mention it.

Think about it this way. If they made a mouse trap so good that it would render all mice extinct, people who make mouse traps would go out of business. So they want to make a mouse trap that sort of works but, not too well. Then you think you are doing the best you can, and continue to purchase more mouse traps. This not only cost the consumer much more money but, I believe it is the biggest waste of energy and natural resources of all time. A 57 Chevy may only get 20 miles per gallon but, has never had a repair in it's million mile lifetime. This would save considerable energy and money over a car that gets 30 miles to the gallon, and has been replaced 5 to 7 times in a million mile lifetime. The manufacturer wants you to think that getting 30 miles per gallon is saving so much energy, that you should be glad to purchase a new car every 100,000 miles. In reality, the new car would have to get 60 miles per gallon to make up for only lasting 1/10th the amount of time as the 57 Chevy. A "fluid system" for the manufacturer, is a "tar baby" for the consumer.

I installed a CSV1Z 3 years ago to prevent well pump cycling during lawn irrigation. My sprinkler system irrigates ~6000 square feet (6+ zones) and delivers ~7GPM over a 80 minute run time, 3-4 days a week.

The pressure switch is set at 40-60psi. Bladder tank pressure at ~38psi. Original 14 year old Red Jacket submersible and

Yield (gal/min) 12
Depth (feet) 298
Level (feet) 70

CSV1Z installation took about an hour. Fine tuning the CSV took about 15 minutes.

We consume ~115,000 gallons per year for a family of 4. Majority of water consumption during short summer.

The CSV works PERFECTLY. On demand, the well pump will kick in at 40psi, build pressure until the CSV1Z set point (56psi) and hold 56psi for the duration of the lawn irrigation, including between zone changes.

Added benefit is during long showers water pressure is constant 56psi.

If you're on a well system and lawn irrigate regularly, the CSV make perfect sense.

Boy would Rancher be mad if he could see that testimonial!

bob...

I have always said that the reason we don't see more of these testimonials for the CSV is because people who have a CSV, don't have problems, so they don't go back to the forum. With the many thousands of CSV's that are installed each year, "No news, is usually good news".