Well Pump Expansion Tank

   / Well Pump Expansion Tank #11  
Looks like a double cap on the Schrader valve. That other part should unscrew the same as a cap on the stem of a car tire. As was said, with most VFD constant pressure systems you want the air charge 30% less than the water pressure set point. It doesn't really matter how large the tank is when using a VFD. The slight drop in pressure needed to energize the pump means the pump will come on after using a cup or two of water no matter how large the tank is. That is just one of the many problems associated with a VFD constant pressure pump. The tank bladder probably went bad because of the VFD as well. The tank bladder doesn't move far but is continually moving a little as the VFD never really locks into a set constant pressure. Changing it out to a CSV constant pressure system will make your life easier and save a lot of money over continually replacing those expensive electronic VFD controllers. The Cycle Stop Valve is designed to make pump system last longer while delivering strong constant pressure. The VFD systems are designed to make money for the installer and pump manufacturer.

Sub Well with PK1A.png
 
   / Well Pump Expansion Tank #12  
@Valveman
I agree with your post, I installed plenty of VFD's that later gave customers problems.
Not much money to be made in Cycle stop valve installations when compared to a VFD install.
 
   / Well Pump Expansion Tank #13  
@Valveman
I agree with your post, I installed plenty of VFD's that later gave customers problems.
Not much money to be made in Cycle stop valve installations when compared to a VFD install.
I know right? And thanks! The CSV was invented to replace VFD's and big pressure tanks in 1993. We were using CSV's to solve the problems of VFD's back then, and CSV's are still solving the problems with VFD's today. The big pump manufacturers labeled the CSV a "disruptive" product in 1994. I had no idea what that was. I soon learned manufacturing a product that makes pumps last longer and use smaller tanks will get you shunned by the entire pump industry. Thirty something years later I am still fighting the same battle. Still trying to keep people from falling for the VFD hype.

I have become a real conspiracy theorist. If they will go to such extremes to hide the facts about pumps, what else are they lying about? "Planned obsolescence" is the number one design criteria in manufacturing, used to keep people purchasing the same products over and over again. For less than 10 bucks a Cycle Stop Valve could be manufactured into and just become a part of most pumps. You should have seen the look on the engineers face when I explained this. Making the Cycle Stop Valve come already installed as a part of every pump would basically put many pump manufacturers out of business. Pumps would no longer cycle themselves to death, which would reduce the number of pumps sold by maybe 90%. Large pressure tanks would no longer be needed, cutting production of tanks by probably 90% as well. Variable Frequency Drives or VFD's would only be needed on a tiny fraction of pump installs with unusual applications, taking billions of dollars out of the pump industry overall.

Adding a Cycle Stop Valve to every pump application would save pump owners billons of dollars, and that is not acceptable to the pump industry. Makes me wonder if they are also hiding the cure for cancer and many other things as well. :mad:
 
   / Well Pump Expansion Tank #15  
So far I've had the VFD going 10 years with zero issues. The bladder tank is also fine. I'm just installing another VFD on a different house that's why I bought it new tank for it
I just had our pump and controller replaced two weeks ago. The last VFD controller and pump was replaced on 2009/10 (can’t remember). It was a one phase power unit; the new one is three phase, so I’m hoping at least to see lower power usage. But my 2hp pump is at 660’ so it works pretty hard. We did install 4 check valves in the pipe at equal distances along the pipe, so it stays charged between demand.
 
   / Well Pump Expansion Tank #16  
I just had our pump and controller replaced two weeks ago. The last VFD controller and pump was replaced on 2009/10 (can’t remember). It was a one phase power unit; the new one is three phase, so I’m hoping at least to see lower power usage. But my 2hp pump is at 660’ so it works pretty hard. We did install 4 check valves in the pipe at equal distances along the pipe, so it stays charged between demand.
You sure on those numbers? According to Oakville, a 2 hp pump is going to run down to about zero flow at just 600 ft. You're 10% deeper than that, and probably looking for nearly 10 gpm for most residential requirements. I'd guess 2 hp might be good down to 475 ft for that, but no deeper.

At 660 feet, I think you'd want at least 3 hp, if not more for a larger house or property with plumbed out buildings or any irrigation.
 
   / Well Pump Expansion Tank #17  
You sure on those numbers? According to Oakville, a 2 hp pump is going to run down to about zero flow at just 600 ft. You're 10% deeper than that, and probably looking for nearly 10 gpm for most residential requirements. I'd guess 2 hp might be good down to 475 ft for that, but no deeper.

At 660 feet, I think you'd want at least 3 hp, if not more for a larger house or property with plumbed out buildings or any irrigation.
I saw the old pump and the new pump, both 2hp. And the flow of the new pump is very good. Maybe the check valves are the answer? It’s a 3 phase Franklin submersible and it’s putting out 9-10 gpm at the house. The well is 680’ total and the pump is at the bottom of 33 20’ pipe sticks.

Edit: I do irrigate all summer and run lawn sprinklers, but one circuit at a time.
 
Last edited:
   / Well Pump Expansion Tank #18  
A 5 gpm, 1 hp pump stops pumping at about 660', so a 2 hp should do just fine depending on the series. 3 phase motor will run better, but will not reduce power consumption, might even be a little worse because of the phase conversion from single to three phase.
Check valves should be installed every 200'. Sounds like your installer did a great job and used top of the line equipment.
 
   / Well Pump Expansion Tank #19  
We did install 4 check valves in the pipe at equal distances along the pipe, so it stays charged between demand.
Not sure but I thought I read somewhere that installing more than one check valve wasn't a good idea. Wish I could remember but it was something to do with one locking up the next one due to pressure being trapped against a closed valve...or something LOL.
 
   / Well Pump Expansion Tank #20  
I saw the old pump and the new pump, both 2hp. And the flow of the new pump is very good. It’s a 3 phase Franklin submersible and it’s putting out 9-10 gpm at the house. The well is 680’ total and the pump is at the bottom of 33 20’ pipe sticks.
Maybe the Oakville table I referenced is not typical. It was just the first I found.

Maybe the check valves are the answer?
Check valves are probably a necessary evil at your depth, but they definitely don't help to compensate for pump capacity. You get a small pressure drop across each check valve, equivalent to the spring pressure divided by bore cross-section, probably just 0.5 PSI. Their function is to avoid system bleed-down, with larger vertical drops (higher pressure at pump).

A 5 gpm, 1 hp pump stops pumping at about 660', so a 2 hp should do just fine depending on the series.
Yep. But he has a 10 gpm pump. Remember, HP is just an ability to do work, that work being the product of both pressure and flow. For a given size motor, you can only achieve higher flow by transitioning to an impeller design that will cost you in pressure.


Not sure but I thought I read somewhere that installing more than one check valve wasn't a good idea. Wish I could remember but it was something to do with one locking up the next one due to pressure being trapped against a closed valve...or something LOL.
I ran into this problem in my last house. What happens is that all check valves have a small leak-down rate. But if one farther down has a higher leak-down rate than one up higher in the system, the result is it pulls a relative vacuum on the line. The pressure switch up top doesn't see this, since it's isolated from the line by a check valve up top. But when the pump kicks on, it's slamming fresh water up into this vacuum, and "bang!"

The system where I observed this had only one check valve up top, just upstream of the pressure switch, as the whole system was only 150 - 200 feet deep. It made a hell of a racket, every time the pump kicked on. I had a well specialist come take a look at it, as my knowledge is just general plumbing (we didn't have wells where I grew up), and it took him about 8 seconds to look at the system and tell me to remove that check valve up top... not necessary. After that, everything behaved well, but I wouldn't know what to do with a 600 ft. deep well.
 
Last edited:

Tractor & Equipment Auctions

PT PTO Driven Canal Pump (A47307)
PT PTO Driven...
2003 Vermac Towable Sign Board (A46683)
2003 Vermac...
2015 Dodge Grand Caravan SE (A46684)
2015 Dodge Grand...
2018 Generac MLT6SM-STD3 6kW Towable Light Tower (A45336)
2018 Generac...
2012 Hyundai Veloster Hatchback (A46684)
2012 Hyundai...
2019 Generac MLTS-1 2.4kW Towable LED Light Tower (A45336)
2019 Generac...
 
Top