Who's Lying? Well Pump & Tank

[Leejosepho]

The good news is tightening the screw to adjust cut-in to 50 and cut-off to 70 and adding the extra 10psi to the tank via bicycle pump DEFINITELY increased my water pressure outside.

Does that mean you now have satisfactory pressure even at the low end of a cycle?

The bad news, the pump is cutting on every 30-35 seconds now instead of once every minute when I run outside sprinklers. This did this with two or three separate hoses running.

Until you are able to use as much water as the pump will deliver, at a pressure that is less than the shutoff pressure of the pump, you will not be able to solve the problem.

Like several of us have said, you need larger pipes, spigots and hoses or whatever to be able to release and deliver a volume of water sufficient to keep the pump running. Or, here is where a CSV could hold a constant 60-or-so psi if that is enough pressure to push enough water through the plumbing and accessories (hoses, etc.) you already have.

 

[DumbOnPlumbing]

Larger Pipes, Etc.

OK, sorry I've lost track of all the different advice from the posts. I really wasn't ignoring them, the thread has just gotten so long.

Below are two photos of what I think you're describing Bob NH. Please let me know if you see any red flags in my interpretation.

Are you saying put the 1" new outside pipe at #1 or at #2 on the diagram?

I would need a four hose connector coming from the new 1" lead, right?

Thank you all again very much. Will get the parts I need from the home improvement store and then see if this is something I can tackle on my own or not. Seems straightforward.

-Mark

 

[Sponsor]

 

[Wet_Boots]

The four-hose connector might not be enough. If that tank is sitting against an exterior wall, you could bring the PVC line to the outside, and repeat your testing without any hoses connected. If you are pumping 12 gpm, then it will be possible that even five sprinklers on five separate hoses won't flow enough water for steady operation.

The higher you adjust the cutoff pressure, the less flow you'll have, at the point just before the swicth shuts off.

 

[Bob NH]

I would tee off the line (1 or 2) that is closest to the line coming in from the pump.

The 1" Tee off the existing line (I assume it's 1") should go outside. From there, install additional 1" tees off that line to give you as many connections as you want. PVC tees are not expensive and the 1" size is more rugged than 3/4".

You can then reduce those down to 3/4", or HD may have tees with 3/4" threaded outlets. You can put a hose adapter on each one with a separate valve, or you can operate all of them from one outside valve. I would use PVC ball valves off the tees.

The 4-in-1 hose connection that you show is too much of a restriction to assure the total flow that you need.

When you run the 1" line outside you can test it by opening that line to make sure that it can discharge the full capacity of the pump.

After that, all you need to do is make sure you have enough hoses and sprinklers to handle the flow.

 

[DumbOnPlumbing]

New Diagrams

OK, What I think you're saying is this...

Any reason I couldn't Tee off right at the top before the water even travels down to the tank?

Also, any idea how this might effect inside water pressure while the 4 or 5 outside spigots are running?

Thanks for all your help, even on the 4th of July. Happy 4th!

 

[Valveman]

And then once you figure out just how large of lines, and how many hoses it will take to keep the pump from cycling, you will ALWAYS have to run this many lines anytime you irrigate. Then to answer your last question, when you are using all the water the pump will produce outside, the pressure will continue to drop when you turn on more water in the house.

This is EXACTLY why a CSV is important. You wound not then need to add anymore lines, hoses, faucets, and sprinklers. The CSV would allow you to run only one sprinkler at a time if you desire, without the pump cycling. It would also still allow you to run as many sprinklers as the pump can supply, or any amount down to just the one sprinkler, as you desire. Then because you are not maxing out the ability of the pump, the pressure in the house would also be constant no matter how many faucets are needed. Sprinklers on or not, once you have experienced a constant pressure shower compared to a shower while the pump is cycling, you will never go back.

 

[Bob NH]

OK, What I think you're saying is this...
Any reason I couldn't Tee off right at the top before the water even travels down to the tank?

Also, any idea how this might effect inside water pressure while the 4 or 5 outside spigots are running?

That setup will work fine. You can tap off before it gets to the tank, as long as there is no check valve between the place you tap off and the tank.

You could even tap off before the pipe from the well comes into the house as long as there is no check valve between that point and the tank.

If you connect enough hoses to operate the system below shutoff pressure when there is no inside usage, then you will not get significant pressure drop inside when you add internal demand.

Most internal uses (showers, toilets, washing machines) are short time relative to an irrigation cycle. I doubt that you will notice the effect.

The number of hoses you need to turn on will depend on the length and size of hoses, and the capacity of the sprinklers attached to the hoses. You will find out what that is the first time you turn them on.

 

[Wet_Boots]

And then once you figure out just how large of lines, and how many hoses it will take to keep the pump from cycling, you will ALWAYS have to run this many lines anytime you irrigate. Then to answer your last question, when you are using all the water the pump will produce outside, the pressure will continue to drop when you turn on more water in the house.

This is EXACTLY why a CSV is important. You wound not then need to add anymore lines, hoses, faucets, and sprinklers. The CSV would allow you to run only one sprinkler at a time if you desire, without the pump cycling. It would also still allow you to run as many sprinklers as the pump can supply, or any amount down to just the one sprinkler, as you desire. Then because you are not maxing out the ability of the pump, the pressure in the house would also be constant no matter how many faucets are needed. Sprinklers on or not, once you have experienced a constant pressure shower compared to a shower while the pump is cycling, you will never go back.

If she didn't have enough sprinkler pressure with a 40/60 setting, then clamping it down to 60 with a CSV won't help much. Pump will be happy. Lawn won't.

If the pressure tank has a 100 psi rating, it would be possible to raise the pressure switch setting higher than 50-70, without risk of damage. Strictly for cheap, you can try it, and do another test (without any hoses connected)

 

[Leejosepho]

The number of hoses you need to turn on will depend on the length and size of hoses, and the capacity of the sprinklers attached to the hoses. You will find out what that is the first time you turn them on.

Overall, this night help a bit here as a point of reference:

I finally got my backyard pool cleaned and filled yesterday. My outside spigots each have their own 1/2" PVC supply lines, and the spigots have about a 3/8" orifice at the valve seat. With 3/4" X 50' hoses connected to each of two spigots, my 1/2 hp submersible pump ran continuously at just under 55 psi and I got 1000 gallons of water at the rate of about 10 gpm.

I suspect having all my spigots on a single 1/2" line would have given much different results.

 

[Bob NH]

I suspect having all my spigots on a single 1/2" line would have given much different results.

It would also make a lot of difference whether you have nozzles on the ends of the hoses, or if they were flowing free with no restrictions.

In the case of the sprinklers, they will cause restrictions so that much of the pressure loss will be at the sprinkler heads instead of in the pipe and hoses.

 

[Valveman]

If you connect enough hoses to operate the system below shutoff pressure when there is no inside usage, then you will not get significant pressure drop inside when you add internal demand.

Most internal uses (showers, toilets, washing machines) are short time relative to an irrigation cycle. I doubt that you will notice the effect.

Of course you will see the pressure drop in the house when you are using all the pump can produce to run the sprinklers. It may be for a very short term but, it is the term that YOU are using the water in the shower that the pressure will be lower. The sprinklers may not notice the pressure drop but, you will.

 

[Valveman]

If she didn't have enough sprinkler pressure with a 40/60 setting, then clamping it down to 60 with a CSV won't help much. Pump will be happy. Lawn won't.

She is seeing the low pressure on the sprinklers BECAUSE the pump is cycling between 40 and 60 PSI. With a 50/70 pressure switch setting and a 60 PSI Cycle Stop Valve, the sprinklers will always be at 60 PSI, which is 30% higher pressure than if it is allowed to cycle at 40/60. You could rent out a room to an engineer, so he can make sure you always have exactly the correct amount of lines and sprinklers running to keep the pump from cycling. Or you can use a CSV, and use water anyway you want, and have great pressure for the house and the sprinklers.

 

[Wet_Boots]

She is seeing the low pressure on the sprinklers BECAUSE the pump is cycling between 40 and 60 PSI. With a 50/70 pressure switch setting and a 60 PSI Cycle Stop Valve, the sprinklers will always be at 60 PSI, which is 30% higher pressure than if it is allowed to cycle at 40/60. You could rent out a room to an engineer, so he can make sure you always have exactly the correct amount of lines and sprinklers running to keep the pump from cycling. Or you can use a CSV, and use water anyway you want, and have great pressure for the house and the sprinklers.

I don't buy your assumption. Sometimes you need more than 60 psi supply pressure, and no large pressure drops from added valves or devices. There isn't anything to prevent the manufacture of an inline plastic CSV with 70 or 80 psi outlet pressure. I say she can keep bumping up the pressure switch settings, and retesting for cycling. I expect the only practical limit is how high a standard pressure switch can be adjusted to, since somewhere around 80 psi cutoff, the spring will just about be fully compressed.

Once the homeowner exhausts the possibilities of higher supply pressures, then more expensive solutions can be examined. There still might be a balance point she can find, without doing anything more. And, to repeat, her testing would be done without any hoses connected to the outdoor faucets.

 

[Valveman]

It is not an assumption, it is a fact. 60 PSI constant is much stronger pressure than 40/60 cycling. 60 PSI constant is also stronger pressure than 50/70 cycling which gives you an "average" 60 PSI. The standard Square D pressure switch will max out at about 75 PSI anyway. And any pressures higher than 70, will make the faucets and shower seals leak, not to mention there should be a pressure relief somewhere, set at 75 PSI which would pop off.

Even a 60/80 switch setting would not reduce the volume produced by a submersible pump by very much. It would however, reduce the amount of available draw down in the pressure tank and could cause the pump to cycle on and off even more.

Then even if the system can be "balanced", it will have to be balanced EXACTLY the same way every single time you run the irrigation. No variations allowed. The CSV will allow you to vary anything, anytime, anywhere, and always have good pressure in the house.

 

[Wet_Boots]

I believe what the homeowner said. That the sprinkler performance was better with a 50-70 setting. I'd want to see what 60-80 might show, if only to eliminate higher pressure settings as a solution. For my own work, sometimes the standard Square D switch is replaced by the next size up, to get a higher range of operation. As for relief valves, I see 100 psi valves these days. But it's worth looking at.

It may very well be that nothing can get enough flow through those 1/2-inch copper lines to prevent rapid cycling. You know, I hope there aren't any long undersized hoses in the outdoor setup. I always love it when someone thinks that a 1/2-inch hose will lead to better sprinkler performance, because "the water's running faster" through the smaller hose.

Nothing whatsoever in home plumbing is subject to spontaneous leaking at pressures under 100 psi, so no worries there. However, high pressures can lead to noiser plumbing when valves close suddenly, like on some washing machines. Once or twice, I've had to balance wells at operating pressures in the 85-90 psi range, and I installed a pressure reducer for the rest of the home plumbing. (talk about constant pressure )

 

[Valveman]

Even if you can squirt enough water through ½" pipe to keep the pump from cycling, you still have to use exactly the same number of hoses and sprinklers every time. If it takes 8 sprinklers to keep the pump from cycling, then you ALWAYS have to run 8 sprinklers. You can never run 7 sprinklers, or 2 sprinklers, or the pump cycles itself to death. I use to try to "balance" the system and tell the homeowners they always have to run 8 sprinklers at a time. Then I realized after having to warranty countless pumps that were cycled to death, that a home owner is not going to always drag out 8 hoses and 8 sprinklers every time they need to irrigate. Especially when they realize that while running 8 sprinklers, they have low pressure in the house. They always end up using less sprinklers, because it is easier and leaves them better pressure in the house. As I have said many times, you can "engineer" and "balance" your irrigation system to exactly match the pump, or you can just use a Cycle Stop Valve. This will let you run any number of sprinklers you want, and still have constant pressure in the house.

Any pressure higher than 75 PSI in the house, and the one handle faucets start leaking in short order. The solenoid valves on the cloths and dish washers cause a water hammer thump. Even the toilet valves will thump when they close. Jacking the pressure up to 60/80 or higher decreases the draw down in the pressure tank.

Using pressure reducing valves on the house lines does give constant pressure in the house but, the pump is cycling while this is happening. Also, pressure reducing valve do what is called "creep". That means in a static, or no flow condition, even though the pressure reducing valve is set at 50 PSI, the pressure on the house will "creep" up to 80 PSI, or the same as the pump system maximum pressure. So when you open a faucet, you get a burst of high pressure before the pressure reducing valve brings the pressure back to 50 PSI.

People have been trying to "engineer" and "balance" around needing a Cycle Stop Valve for years. Wouldn't it be better to just learn how to utilize the tools that are available, instead of spending so much time trying to figure a way around them? You can also drive a nail with a rock, and then you wouldn't need any "speciality" tools. But a hammer is the best way to drive a nail, and a CSV is a best way of controlling pumps. Using the right tool for the job makes every bodies life easier.

 

[Wet_Boots]

I think we're headed in the same general direction, but I'd be advising the enterprising questioner to try the zero-cost options first. Evaluate the results, and move from there.

As much as you love your CSV, it is not a fits-all solution, not until a higher outlet pressure is available in the low-loss versions. I continue to encounter situations that require high-pressure operation and balancing of flows. Sometimes, such a situation can arise from a replacement pump of higher horsepower than the original, and a re-replacement of the pump is not an option.

I spent too much of my life in a town with 100+ pressure (and no reducers) to place much faith in any flat statement that faucets et all will self-destruct at high pressures. They will wear out faster, no doubt, but washing machine hoses aside, explosions aren't in the picture.

As for a pressure reducing valve allowing the pressure to 'creep' above its set value, please link us a page from some reliable third party that explains this phenomenon, as it is something I have never personally observed. And since I use PRVs in places where the street pressure could blow apart some of the plastic plumbing (valves in particular, poly hydrant lines, as well) I believe I would have known about this 'creep' before now.

 

[Valveman]

Boots, just do a search for (creep pressure reducing valve). I have a few valve engineering books that talk about it but, I would have to scan. Valve manufacturers don't like to admit it but, there are plenty of "creep resistant" patents and materials on the market to give you some good reading. Maybe when the valve is new, creep is not much of a problem. Just think about what happens when the seat wears a little, or a chunk of rust gets under the seat. Don't count on a pressure reducing valve to keep high pressures off piping systems. A pressure relief after the pressure reducer helps but, it can also stick closed after months of non-use. All the valve classes I have attended talk about creep and how best to try and prevent it. It is not if, but when.

 

[Wet_Boots]

If a PRV is defective, then it won't seal 100 percent, and you could get that creep, but I never, ever, have done pressure readings on PRV-equipped homes, and seen more than what the set point of the PRV was. This includes unoccupied homes, with nobody using any water, and with expansion tanks to hold some excess pressure for me to observe.

Obviously, seats can wear, which is why large supplies should be reduced through more than one PRV set up in a ladder array. But if the phenomenon was common with new equipment, there could be a lot of unhappy homeowners with burst plumbing, with street pressures exceeding 150 psi.

But in any event, PRV creep, whatever the statistics on it are, is irrelevant to using the devices in home plumbing. Lower pressure is desired, so a PRV goes in, and I get to balance a well in the mid-80's, and make up for very-expensive-to-replace plumbing that became undersized when a 1/2 HP pump got replaced with a 3/4 HP pump.

 

[Bob NH]

I'm looking forward to the report from the original poster when those multiple ball valves get connected. The sprinkler performance with the 50/70 switch setting will be great and the only question will be how many hoses can be run at the same time on the pump.

The question about varying house pressure is really insignificant if you think about it.

The only thing where variable flow would matter is the shower. They are all supposed to be controlled at 2.5 GPM per head. All of them have a little rubber insert that works like a Dole flow-control valve. The standard is that a legal shower head must deliver not more than 2.6 GPM at 80 psi or less.

Because of the flow-control characteristics of the shower head you will see virtually the same flow over the full range of a normal pressure switch.

You will get more variation in toilets, dishwashers, washing machines, and faucets, but it makes no difference in performance.