Do I need a well pressure tank?

[Yar02169]

Hello-

I use my well and pump just for irrigating my lawn and upsetting my neighbors with a green lawn. I've detected a leak near my pressure gauge, so my plan is to rebuild that part of the system. I'm wondering if I need the pressure tank. The current tank is a baby, maybe 4 gallon or so. I have yet to get the system working on the automatic timer, and I would like to blame the tank for not being adjusted properly. I'm trying to figure out why I have a tan in the first place. When a solenoid opens, pressure drops, pressure switch turn on pump. When time is up, solenoid stops flow, pressure raises and switch shuts off pump.
Does the tank act as a surge protector when the solenoid closes, acting like a safety cushion for the pvc piping? When I water, the pump will cover 5 zones, each zone running for at least a half hour. With no short term water usage, do I really need the tank? I'll trust you guys, so if you say I need it, I'll rebuild and use it, even if I think the tank is ugly and not needed.

Thanks!

 

[DonL]

Irrigating a lawn may be band in many areas soon. It is around here now.

Your application sounds like a small tank will work using one of Valveman's systems.

I would say Yes, You do need a small tank. None may not be so good, but it may work.


Good luck.

 

[Sponsor]

 

[LLigetfa]

If you rely on a pressure switch to turn on the pump then you need a tank with a proper air charge.

 

[DonL]

If you use it just for "I use my well and pump just for irrigating my lawn and upsetting my neighbors with a green lawn."

Ask your neighbor what you need. If they report you, you may have no water.


If You want Bragging rights ? Then get his wife. And watch out for those bullets.


Sorry but I call it like I see it.


And Please correct me if I am wrong.


Why would you want to upset your neighbor ? You should help each other.

 

[Yar02169]

Wells, and irrigation systems, are a rarity around my neck of the woods. Water is cheap and plentiful, but using water to take care of your lawn also means your paying a sewage bill that your not 'donating' to. They won't be banned anytime soon around here (Boston).

I guess I'm wondering what the purpose of the tank? I now for a home-use system, it lessens the amount of pump runs. In my case, is it needed? What happens if I don't use a tank?

 

[DonL]

Wells, and irrigation systems, are a rarity around my neck of the woods. Water is cheap and plentiful, but using water to take care of your lawn also means your paying a sewage bill that your not 'donating' to. They won't be banned anytime soon around here (Boston).

I guess I'm wondering what the purpose of the tank? I now for a home-use system, it lessens the amount of pump runs. In my case, is it needed? What happens if I don't use a tank?

You did have the purpose of the tank correct.

But pissing off your neighbor is not correct.

 

[Yar02169]

In that case, I shouldn't need a pressure tank. It will turn on and run at a minimum of an hour, maximum 2.5 hours. The only thing the baby 4 gallon tank does is sit there and maybe provide some two gallons of down-flow before the pump turns on via the pressure switch. When the watering is done, the solenoid shuts, pressure builds, and the pressure switch shuts the pump off.

Even if I happen to open the hose faucet, the pressure drops and the pump turns on. Shut the faucet off, and the pressure switch will shut the pump off.

Am I missing something, or is there actually no reason for a pressure tank in this use? The pressure switch does all the work, the pressure tank just delays the pump start, correct? I have no intention of rinsing my hands, which is probably the reason for the pressure tank in home use.

As for the neighbors, there's always one jerk that has the greenest lawn, and I strive to be him. ;-)

 

[Valveman]

Even if I happen to open the hose faucet, the pressure drops and the pump turns on. Shut the faucet off, and the pressure switch will shut the pump off.

With a 4 gallon tank that only holds 1 gallon of water you probably already have a Cycle Stop Valve in the well or somewhere you can’t see. The sprinkler system maybe matched to the pump and using enough water to keep the pump running, but without a CSV that pump would cycle on/off like crazy while you are running the garden hose.

the pressure tank just delays the pump start, correct

Without at least a gallon in a pressure tank, the pump would come back on every time your system leaks a thimble full of water. A small leak, a drippy faucet, or a solenoid valve that doesn’t quite close off will cycle your pump to death quickly.

You could do away with the pressure switch and start or stop the pump with the pump start relay in the sprinkler controller. But then you can’t use a garden hose unless one of the sprinkler zones is on and the pump has started.

When using a pressure switch a pressure tank is very important. When using a small pressure tank a CSV is very important.

 

[Yar02169]

Thanks valveman, your explanation is helpful.

I don't have a csv in the system at all (do I need one?). The system does operate very nicely, no cycling or anything, even with a hose. I was thinking that if I redo things to look better and eliminate a known leak, the fewer connections the better in preventing future leaks.

I guess I'll do the rebuild with the tank figured in.

I do have another possibly silly question. The tank, gauge and pressure switch are above the pump. Is there need to be a bleed to get air out of the branch when the pump runs? Will it be an air lock or will the air somehow purge out of there? As long as I'm re-configuring, I might as well do it right.

 

[Valveman]

Do you have a submersible pump or an above ground jet pump?

 

[Yar02169]

It's a jet pump set up. The picture shows the current set-up (don't envy my Flo-Tec). I plan to arrange it differently so that there's easier access to the pressure switch, but it would more or less look the same. My thought is that air is and will be trapped in the branch.

 

[Valveman]

That pump can't build enough pressure to cycle, even while running just a garden hose. But if you don't have a good tank, it will cycle every time you lose a few drops of water.

 

[Yar02169]

The pump does the job without any complaints.

Will trapped air in that branch cause the pressure switch, or the air tank to act strange? Might as well change it up if there's a better way.

 

[Valveman]

Trapped air is only a problem if it starts spurting out your faucets.