Adding tank to existing system to extend cycle time

Users who are viewing this thread

TheOldMan

New Member
Messages
2
Reaction score
0
Points
0
Location
Florida
I have a 1.5 hp submersible pump system with a bladder tank. The distribution system is 1.25 PVC from well head to manifold and tank. Domestic water is 1" to home and outbuildings. 1.5" PVC to lawn irrigation and outdoor hose bibbs. We grow approx. I acre garden, and have been irrigating with a 3" trash pump from an older 4"well from back of property. Suction side of that system is 2"-20' down well with foot valve. Electricity is 500' from that well. Decided it would be better to irrigate from existing domestic well. We irrigate with t-tape, utilizing pressure regulating valve @15psi, .34gpm/100' of tape, approx. 6000' of tape total. We inject fertilizer into the t-tape (fertigation) so will install pressure vacuum breaker between garden and rest of system. Well should supply about 28gpm, total draw s/b about 21gpm.
In order to stop rapid cycling of the pump, thereby shortening it's life, I have acquired a 120 gal vertical fiberglass tank (retention tank?) That came off a domestic water chemical injection system that failed. Looks like a Well Mate UT. Bottom of that tank has a tee w/2 1"ball valves. Top has a 1.25 fpt fitting. I am assuming that by adding an additional 100 gals of pressurized water would add run time between on/off cycles of the pump. Info that I have gleaned off the web, when used as a retention tank, water comes in at the bottom - one valve - other one for drain, and water is taken off the top incorporating an atmospheric vacuum breaker, to feed the using system. Since the intent here is to use the tank for pressurized storage rather than retention for chemical mixing, a better piping scheme would seem to be to bring water into one side of bottom tee and out the other side to the irrigation system, and block off the top outlet, once the tank was full. This is where I get lost. As the water was used, the level in this tank would fall. Everything I read indicates that these tanks will not withstand vacuum, so AVB would have to be installed in the top plug to keep the tank from imploding. If one does that, and the tank starts to fill, it would compress the air in the top that was admitted by the vacuum breaker, and you no longer have a storage tank but more likely another pressure tank. I think that defeats my purpose. I'm researching cycle stop valves, but would like to incorporate this tank, since I have it, and am curious. Thanx in advance for any help and advice.
 

Valveman

Cary Austin
Staff member
Messages
14,599
Reaction score
1,296
Points
113
Location
Lubbock, Texas
Website
cyclestopvalves.com
I believe you are thinking too hard about this. A Cycle Stop Valve will work with the bladder tank you have. Then you can use the water at any rate above 1 GPM without cycling the pump. Even if you need a new tank, a little 4.5 gallon size tank is all you need with a CSV.

You won’t be able to use a bleeder or air injector system with that retention type tank, so it will stay waterlogged and worthless as a pressure tank. You can’t use an air injector system with a bladder tank, and you must use an air injector system with a non-bladder tank, so they don’t work well together.

I don’t see any use for that retention tank except to take up space. Sorry!
 

Reach4

Well-Known Member
Messages
38,796
Reaction score
4,412
Points
113
Location
IL
As the water was used, the level in this tank would fall. Everything I read indicates that these tanks will not withstand vacuum, so AVB would have to be installed in the top plug to keep the tank from imploding. If one does that, and the tank starts to fill, it would compress the air in the top that was admitted by the vacuum breaker, and you no longer have a storage tank but more likely another pressure tank. I think that defeats my purpose.

How would you get the water out of that storage tank? Gravity through tubing to a nearby drip system?
 

TheOldMan

New Member
Messages
2
Reaction score
0
Points
0
Location
Florida
Adding tank

How would you get the water out of that storage tank? Gravity through tubing to a nearby drip system?
The tank would be part of the pressure system, upstream of the pressure reducing valve and irrigation manifold.
Valveman - wouldn't adding this alve in line give me an extra 100 gallons of water before turning on the pump? What I've read here, is that the pvc piping system expands somewhat under pressure and adds to the amt of water prior to cycling on - wouldn't this tank do the same thing?
 
Last edited:

Valveman

Cary Austin
Staff member
Messages
14,599
Reaction score
1,296
Points
113
Location
Lubbock, Texas
Website
cyclestopvalves.com
The tank would be part of the pressure system, upstream of the pressure reducing valve and irrigation manifold.
Valveman - wouldn't adding this alve in line give me an extra 100 gallons of water before turning on the pump? What I've read here, is that the pvc piping system expands somewhat under pressure and adds to the amt of water prior to cycling on - wouldn't this tank do the same thing?

No! As I explained earlier, IF you could keep the right amount of air in that 120 gallon tank, it would only deliver about 30 gallon if water. 90 gallons of the tank must be filled with compressed air to work as a spring to push out the 30 gallons. And even IF you could keep the right amount of air in the tank and get 30 gallons of draw down, it is not going to last but 1 1 /2 minutes when using 20 GPM on the drip system. It is more important that the pump doesn't cycle WHILE running water than it is for the pump to wait 1 1/2 minutes to come on, and that is where the CSV does its job.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks