Pros, please check me on this before I buy a new pressure tank - THANKS!

[Yi Ma]

"Well Pressure Tanks store water from your well and reduce wear on your pump by avoiding the necessity of your pump switching on and off constantly as people in your house use sinks, showers etc. Also well pressure tanks help to keep the water pressure constant in between operations of your pump. If you don’t have a good well pressure tank and you are having a shower, you may well feel the temperature of the water suddenly increase and burn you if someone flushes the toilet! This is due to the water pressure of the cold water supply dropping when someone else uses cold water."

Well I will offer a couple of corrections. First a pressure tank does not "avoid the necessity of your pump switching on and off constantly as people in the house use water". Switching on and off constantly is what a pressure tank CAUSES the pump to do. The larger the pressure tank, the less if cycles on and off, but it still continues to cycle constantly while water is being used. So well pressure tanks do not keep the pressure constant. The pressure is constantly changing from 40 to 60 while you are using water. Then even if you have a good pressure tank, you will still feel the temperature in the shower suddenly increase and decrease as the pressure constantly changes from 40 to 60 and 60 to 40 over and over.

A Cycle Stop Valve set at 50 PSI would keep the pressure at a constant 50 while water is being used. This keeps the pressure steady at 50 for as long as you are in the shower or using water anywhere, which eliminates the sudden changes in pressure and temperature when someone flushes a toilet or uses water elsewhere. But then you would only need a 4.5 gallon size pressure tank, as the CSV makes the water go right past the pressure tank directly to the shower or faucets, which makes a large tank completely unnecessary.

"The larger your tank, the better, in terms of minimizing on-off cycling of your pump."

If using a larger tank is better in terms of minimizing on/off cycles, and it is, then using a CSV to completely eliminate on/off cycling is even better.

"A larger tank also will cut your electricity bill, as there is a current surge each time the pump is turned on and reaches operating speed."

It only takes a regular pump a fraction of a second to get to operating speed. So you could start a pump 300 times per day and you would not be able to see a difference in the electric bill from a pump that started 20 times a day using a larger tank. But there is a slight increase in energy consumption for pumps that cycle on and off a lot. That being said, a CSV will completely eliminate cycling when water is being used for long periods of time. So using a CSV and small tank to keep the pump running constantly would use less starting energy than a system with any size pressure tank that continues to cycle on and off.

I still use 86 gallon WX302 pressure tanks, but only to run large pump systems like in post #7 where with a CSV it supplies water to a city with 20,000 people. Big pressure tanks for use in single houses have become obsolete, as there are now much better ways to eliminate, not just reduce the pump cycling.

Hi Valveman,
Thank you very much for replying in such detail! I will adjust the article accordingly.

 

[Craigpump]

Yeah some pumps will last that long. But it is in SPITE of all that cycling, certainly not BECAUSE they are allowed to cycle excessively.

Common sense tells you that the fewer times you turn on a light bulb, activate a car starter, turn on a TV or radio, the longer they will last.

Why would a pump be any different?

Same with a tank, the fewer times you stretch the diaphram, the longer it will last.

Granted, there are a few exceptions to the rule, but those are the exceptions and not the rule.

 

[Sponsor]

 

[Valveman]

Hi Valveman,
Thank you very much for replying in such detail! I will adjust the article accordingly.

Thanks for updating your blog, and for mentioning Cycle Stop Valves. However, I still see a few incorrect statements in the blog. I will quote and correct them for you as follows in bold.

"Well Pressure Tanks store water from your well and reduce wear on your pump by avoiding the necessity of your pump switching on and off constantly as people in your house use sinks, showers etc. Also well pressure tanks help to keep the water pressure constant in between operations of your pump."

Well pressure tanks are designed to minimize the number of on/off pump cycles while you are using water, and are not designed for storage. They accept excess water from your pump when the rate being used is less than the pump produces. Without a properly functioning pressure tank, the pump would be switching on and off every second, which is extremely bad for the pump. The larger the pressure tank, the longer the pump runs before the tank is filled to 60 PSI (pump stop), and the longer the pump is off when it is being drained to 40 PSI (pump start). With a pressure tank system, the water is never held at a constant pressure. As water is being used, the pump is continually cycling on/off between 40 and 60 PSI, The larger the tank, the less the pump will cycle. The less the pump cycles, the better it is for the pump.


"With a storage capacity of up to 32 gallons" with a 119 gallon size tank, "this Amtrol Well X-trol stand tank has received rave reviews from online customers"


"The good quality diaphragm in this tank will help keep constant pressure in your water system."

The good quality diaphragm in this tank will make it last longer as it flexes up and down with each pump cycle.


A 119 gallon size pressure tank "has got a volume enough to accept 32 gallons."


“Unlike the Amtrol tank that has a diaphragm to keep the water under constant pressure,”

The wording “to keep the water under constant pressure,” should be removed.


"Although this tank is a 19 gallon tank, Flotec claim it has a performance equivalent to a 44 gallon diaphragm tank."

This is not possible. They may say a 19 gallon tank has the same performance equivalent to a 42 gallon galvanized tank, but it will be the same as a diaphragm tank.

 

[RinFt Worth]

Valveman,
I stumbled across this thread as I was researching the replacement of a well pressure tank at my home.
Current tank setup is an 81 gal and about 12 years old. I live in Ft Worth TX and have been told our wells are about 400 ft deep around here (Im not the original owner so I am not certain). The tank and 40/60 pressure switch are in the garage. The well is in the back yard about 50 ft or so behind the house. There is a "Big Blue" type sediment filter in the garage just prior to the pressure tank. I have been using a pentek spun rope type filter element in this.

I am interested in the cycle stop valve and have a couple of questions-
1. I see a couple of different designs available on Amazon. Is the valve in the link what I should be looking for?
https://www.amazon.com/CYCLE-VALVE-...d=1466544363&sr=8-4&keywords=cycle+stop+valve
or is this a better option?
https://www.amazon.com/PSIDE-KICK-C...d=1466544363&sr=8-2&keywords=cycle+stop+valve
What do you usually install at a single family home with 4 people and an irrigation system?

2. If I were to install something such as this - what size tank do I go with?

3. My well pump pressure relief is a 75psi valve and is at the top of the well connections - I learned about this valve not long after moving in when it kept opening and spewing water out. After some troubleshooting I figured out that the big blue filter element was clogged enough that very little water was able to get past it - thus opening the pressure relief valve. As part of my troubleshooting I installed a pressure gauge at the well and when the pump is on there is about 90 psi coming out of the well. It seems to me that a CSV would cause my pressure relief valve to open every time the pump was running. Is this accurate? How should I plumb around this?

Thank you for any help/advice you can give me.
Rick

 

[Valveman]

Since you are replacing the pressure tank you will need the Pside-Kick kit that comes with a new pressure tank, CSV, pressure switch, and all the other stuff needed. It even includes another pressure relief valve, which is installed in the correct location, after the CSV. You will just need to remove the pressure relief valve at the well head, as the PRV needs to be after the CSV, as it is in the Pside-Kick kit.

You should also move the filter to the pipe after the Pside-Kick kit. You never want to put a filter before the pressure tank/pressure switch for reasons you described earlier. It is a good thing the pressure relief popped off or the clogged filter would have burned up the pump. That cannot happen when the filter is installed in the correct location after the tank and switch.

And here is where you will want to get your Pside-Kick kit.
https://cpkits.com/products/pk1a