Pressure Tanks in Series

[markinnc]

Our well pump failed and it cost $2,700 to replace (ouch). The technician put in a 3" 3/4HP 10 GPM Grundfos SQ10 - 290 replacing a 4" 1 1/4 HP Fairbanks Morse. The old pump and a Well-X-Trol 302 86 Gallon pressure tank were installed in 2006.

I am uncomfortable having an old pressure tank and am exploring adding a second tank in series. The Amtrol website tank sizing tool reports a 44 gallon tank is correct for this 3/4 hp 10 GPM pump. Research indicates that a larger tank is better in general. So my tentative plan is to install a 44 gallon tank in series as a fail safe and to create a larger reservoir.

Does the new tank benefit from a pressure relief valve and drain or is it functional to do a simple t into the existing water line? I understand both tanks need to be charged at the same pressure. Other considerations?

When the old tank eventually fails would it make sense to add a second 44 gallon tank to replace the 302 to further extend system life and redundancy? If not can I leave the bad tank hooked up?

Am I overthinking this? What is the actual risk that the pump will get damaged when the old tank eventually fails if I monitor system behavior?

Thank you!!!

 

[Valveman]

I have not recommended a larger pressure tank for over 30 years. Sure cycling on and off is what caused pumps to fail. But a larger tank just reduces the number of cycles somewhat, it doesn't eliminate them. Manufacturers recommended tank sizing is to just get the equipment to last past the warranty period. They don't want it to last any longer than that or they would recommend a Cycle Stop Valve. A Cycle Stop Valve will work with a very small pressure tank and make the pump last many times longer than planned by the manufacturer. Oh. and BTW, the CSV will deliver such strong constant pressure to the house that you will no longer need soap in the shower. Lol! Can't so any of that with a large pressure tank. The CSV will work with any size tank. If your tank is still good, use it. The Cycle Stop Valve eliminates so many pump cycles that it will even make the diaphragm in that old tank last many more years.

 

[markinnc]

Thank you for your point of view. This response does not address a conventional system and installing a CSV is controversial from what I have seen online.

 

[sarg]

Just to mention ...... I followed Valveman's guidance several years ago now. No regrets.

And as just another opinion .... what you are pondering is far from "conventional". By the time you pay for the additional T fittings and "plugs" for a second tank you've spent more than the CSV would cost to gain minimal value added. (All your controls --pressure switch etc. would be on the second tank only ) A 40 gallon tank holds about 13 actual gallons of water .... is 13 more gallons worth the expense ?
If you're uncomfortable with the existing "old tank" .... just replace it

 

[Valveman]

Thank you for your point of view. This response does not address a conventional system and installing a CSV is controversial from what I have seen online.

My response does address a conventional system. Adding a CSV solves the only problem associated with a conventional system, which is cycling. All the literature from pump and tank manufacturers suggest ways or tank sizes to mitigate or reduce the cycling problem. But they don't want you to use a Cycle Stop Valve and actually solve the cycling problem, or you may never have to purchase another $2700 pump or tank in your lifetime.

Thanks Bannerman. When something sounds too good to be true, it usually is. The Cycle Stop Valve is an exception to that rule. But it doesn't make it easy to sell when it works so well it sounds like Snake Oil. Lol! Only people who have never seen one work or have no idea how pumps actually function would say anything negative about a CSV. It is certainly not controversial to anyone who has a CSV as you can see from a few hundred of the most recent reviews here. Reviews – Cycle Stop Valves, Inc

With a 30 year track record and a company that stands behind their product, satisfaction is guaranteed. You can either listen to the fake news on the Internet, or do some real research. If you don't want strong constant pressure or your pump to last a long time, then don't add a Cycle Stop Valve. Your pump man will appreciate it.

 

[markinnc]

I came to this forum to get information from independent people not to purchase a particular solution from a vendor. However, I am open minded and am currently doing the research and am thinking critically. One criticism that made sense to me is that a CSV turns on every time I wash my hands or flush the toilet. Apparently, a larger tank with a conventional pressure switch reduces cycles. Do you have data to support verbal cycling claims? Please bear in mind, I operate from a trust but verify methodology.

Based on research to date it appears cheaper and effective to T in a second tank as a fail safe than to replace a working system. Are you willing to help me complete an objective straight up cost benefit analysis between the four possible solutions? I am willing to explore a CSV again. FYI, my background is financial and I often use financial models to make decisions.

Logically, I can choose from one of the four solutions below in a probable ascending cost order. Maybe the long term cost of CSV is in fact best but this isn't a brand new install and home ownership expectancy is a personal investment consideration.

Do nothing

Add a second tank in parallel

Replace Tank & some or all of existing valves

Install a CSV

 

[sarg]

"One criticism that made sense to me is that a CSV turns on every time I wash my hands or flush the toilet"

You clearly do not understand the function of a CSV.

READ= Basic Operation of a Cycle Stop Valve – Cycle Stop Valves, Inc

 

[markinnc]

That is why I posted here, I am a DIY homeowner seeking support in making an independent decision. The statement should have said pump turns on. So what specifically am I missing? Why does your picture have what looks to be a conventional pressure switch in the system? Isn't that component eliminated?

 

[sarg]

Why does your picture have what looks to be a conventional pressure switch in the system? Isn't that component eliminated?


NO ... Please read >>> Basic Operation of a Cycle Stop Valve – Cycle Stop Valves, Inc

 

[MicEd69]

Why does your picture have what looks to be a conventional pressure switch in the system? Isn't that component eliminated?

Not to be mean, but if you do not understand that a pressure switch is required for ANY well system, then your statement "a CSV is controversial from what I have seen online" is simply believing "online" comments without understanding basic well systems.

I'm a Registered Professional Engineer and Major Project Manager that have handled $160 and $175M projects in refineries, chemical plants, and agricultural facilities. So, I have experience in mechanical/fluid systems as well as financial considerations of installations.

I applaud you desire to fully understand the mechanical/fluid system operations of a well before you make a decision. I would just caution you on believing everything you read on the internet. Sometimes things do not make sense to those who think they have very logical minds. There are even plumbers on this forum who do understand or perhaps believe a CSV system will improve equipment lifespan as well as provide constant pressure to the house.

 

[sarg]

And be aware it took several "years" to sorta understand and I still don't have it all figured out.

 

[Valveman]

I came to this forum to get information from independent people not to purchase a particular solution from a vendor. However, I am open minded and am currently doing the research and am thinking critically. One criticism that made sense to me is that a CSV turns on every time I wash my hands or flush the toilet. Apparently, a larger tank with a conventional pressure switch reduces cycles. Do you have data to support verbal cycling claims? Please bear in mind, I operate from a trust but verify methodology.

Based on research to date it appears cheaper and effective to T in a second tank as a fail safe than to replace a working system. Are you willing to help me complete an objective straight up cost benefit analysis between the four possible solutions? I am willing to explore a CSV again. FYI, my background is financial and I often use financial models to make decisions.

Logically, I can choose from one of the four solutions below in a probable ascending cost order. Maybe the long term cost of CSV is in fact best but this isn't a brand new install and home ownership expectancy is a personal investment consideration.

Do nothing

Add a second tank in parallel

Replace Tank & some or all of existing valves

Install a CSV

I came to this forum to give accurate information to those who have been led astray by ill-informed independent people or flashy high dollar marketing campaigns by big manufacturers. I understand reviews can be made up as well. So, all of the hundreds of our most recent reviews have pictures to prove they are all from different "independent" people.

I also understand the misconception that the small tank with a CSV means the pump comes on for every toilet flush. With 55 years of pump experience, several patents to my name, I have spent the last 30 years trying to understand all the benefits of the Cycle Stop Valve. When we first started in 1993, we thought all it did was stop the pump from cycling, so we called it a Cycle Stop Valve. Now we understand that almost everything about a pump system benefits from a CSV in some way.

First off, if you are worried about the small tank, use the CSV with the existing WX302 tank. That 86 gallon size tank only holds 20 gallons of water. Without adding a Cycle Stop Valve the pump will cycle 15-20 times a day to refill that pressure tank, supplying 300 gallons the house uses everyday. Adding a Cycle Stop Valve to the existing "conventional" tank would decrease the number of cycles per day from 15-20 to probably 6 or 8 times.

Here I was ready to type for another hour and Mark called me. Had a long conversation. Hope I answered his questions. Still glad to explain anything we haven't covered. Just let me know. I appreciate the call.
Cary

 

[sarg]

Adding a Cycle Stop Valve to the existing "conventional" tank would decrease the number of cycles per day from 15-20 to probably 6 or 8 times.

Mr. Austin --- I understand when there is a continual draw & the CSV maintains a steady input PSI ..... but how does the above work ?

The usage draws the water from the pressure tank ( no matter the size ) and when it reaches the start pressure the pump is turned on. The pump runs ( no usage draw ) until the tank pressure reaches the off pressure and the tank is full. The pump will not activate again until the water is used from the tank and the psi hits the start pressure. Without continual usage how does the CSV diminish the cycles ? ( Assuming just intermittant water usage )

 

[markinnc]

Cary Austin was terrific on the phone. I appreciate and respect people who have spent their careers in this field. Candidly, I could only take in a fraction of the knowledge offered. During the conversation, I did learn 3 very important things.

1. I can use a cycle sensor Cycle Sensor Pump Monitor – Cycle Stop Valves, Inc to protect the pump in the event of a pressure tank failure. I am primarily seeking to protect my pump investment and this is the cost effective fail safe solution.

2. A CSV works in conjunction with a pressure tank so the pump does not turn on for small uses of water... This seems to be a common confusion online. I also better understand how a CSV works in conjunction with and extends the life of well water equipment.

3. I respect Mr. Cary Austin as a leading industry professional! Thank you sir!

I also thank everyone else for their help! Confusing stuff for a newbie :>)

 

[Twowaxhack]

Without continual usage how does the CSV diminish the cycles ? ( Assuming just intermittant water usage )

Excellent question.

 

[sarg]

A CSV works in conjunction with a pressure tank so the pump does not turn on for small uses of water

And now I have another question -------- How ?

 

[markinnc]

A CSV works in conjunction with a pressure tank so the pump does not turn on for small uses of water

And now I have another question -------- How ?

In our conversation I defined small uses like toilet flushing or washing hands. Cary stated these activities use less than the cycle capacity of the pressure tank. If I understood correctly, the CSV runs only when the pressure switch is triggered. I still need to read the link you provided earlier. We will need Cary or another expert to verify these statements.

 

[Valveman]

Adding a Cycle Stop Valve to the existing "conventional" tank would decrease the number of cycles per day from 15-20 to probably 6 or 8 times.

Mr. Austin --- I understand when there is a continual draw & the CSV maintains a steady input PSI ..... but how does the above work ?

The usage draws the water from the pressure tank ( no matter the size ) and when it reaches the start pressure the pump is turned on. The pump runs ( no usage draw ) until the tank pressure reaches the off pressure and the tank is full. The pump will not activate again until the water is used from the tank and the psi hits the start pressure. Without continual usage how does the CSV diminish the cycles ? ( Assuming just intermittant water usage )

You are exactly correct. When there is no more usage, the CSV lets the tank fill and the pump shut off. Even with a large (20 gal draw) pressure tank, without a CSV, any use of water more than 20 gallons will cause an additional cycle.

But during the day if there are 4-5 uses of water that are more than 20 gallons, A CSV will eliminate 4-5 cycles by just keeping the pump running until you are finished using water.

This chart, made by one of my customers, shows using a larger tank with a CSV will reduce the cycle somewhat compared to a CSV with a small tank. Only shows a 20 gallon tank (5 gallon draw) but it scales up with even larger tanks. But also notice the CSV with the small tank cycles about the same as a larger tank without a CSV.

 

[Valveman]

A CSV works in conjunction with a pressure tank so the pump does not turn on for small uses of water

And now I have another question -------- How ?

Well, even the 4.5 gallon size tank lets you use 1.2 gallons of water before the pump is started. That size tank will cause the pump to start for a 1.6 gallon toilet flush. The 10 gallon size tank holds 2.4 gallons of water, and will let you flush a toilet without a pump start. However, it is not a problem for the pump to start after using only a gallon or two or water. What is important is the pump does not cycle on and off WHILE water is being used. With the CSV filling the tank at 1 GPM rate, a tank that holds 1 gallon of water becomes a mechanical timer to keep the pump running for another 60 seconds after a toilet finishes filling or the shower is turned off. During that 60 seconds if you or someone else in the house opens a tap, the pump just continues to run to supply the new demand, and then starts the 60 second time delay again. This doesn't help much at 2AM when a single toilet is flushed. But during peak hours of the day it keeps the pump running for 30 minutes, an hour, or even longer as everyone in the house is getting ready for the day or cleaning up after a long day. Without the 60 second time delay from the CSV the pump would have shut off and cycled back on several times during the same period.

Plus, the time delay keeps the pump running while the toilet tank is filling and then for another 60 seconds after the toilet has finished filling. So, if you stood there and flushed the toilet a thousand times a day, the pump would only cycle once as the CSV would keep the pump running 24/7 until you stopped flushing. If you stood there and waited a couple 2-3 minutes after each toilet flush before flushing again, the pump would cycle on and off. But it would be on for 2-3 minutes and off for 2-3 minutes. Which, even with a small tank is less cycling than when using tank manufacturers recommended tank size for 1 or 2 minutes of run time.

To be such a simple valve the CSV has a complicated explanation. Having been fascinated with pumps and studying them extensively since the first one I saw in 1968, I still learn something new everyday. It has taken me 30 years so far to understand all the benefits of the Cycle Stop Valve, and I am still learning new things everyday. The CSV is even harder to explain to people who do not have the many years of pump experience that I have. As Mark found out, I can talk for hours on this subject and still never really get very deep into the specifics. Lol!

I appreciate you guys making me type this out as best as I can. But it is even harder to explain in writing and takes a lot of typing. I want to pass on what I have spent a lifetime learning, so I try. I have eaten, lived, and breathed pumps for many years. It was all I could think about. But now being somewhat retired, all I want to do is play with my granddaughter or clear brush with my little bulldozer. Lol! Thanks for asking the questions. Cary

 

[Ludington]

I think it depends on your specific situation and water use. If you use a cycle stop with a small pressure tank, and you have someone that washes thier hands every 10 minutes (my wife does this, wants no chance of spreading germs or cross contamination when cooking) your pump is going to cycle more than if you have the larger 80 gallon tank. This (in my opinion) is for users that have long run cycles and small tanks (sprinkler systems, long showers , whatever)
My particular situation , you would think I would benifit (I run a geothermal heat pump from my well) it draws roughly 25 gallons each time it turns on.
I have monitored it, and my well runs once for each cycle. And if it happens to be a day where it's not running, my pump will run once or twice. So, for me, I do not believe it buys me anything. It could save a cycle or 2, but to me it just adds another point of failure. But again, that's my situation, everyone needs to evaluate your own water use and if there is a benifit.
I think having 2 80 gallon tanks is a bit overkill, but if it makes you have less anxiety ... I have read someplace well pumps are built to do 250-300 cycles per day. It may have even been stated by valveman. The way they make pumps these days, I also read that 10 years and your lucky.