Setting Well Pressure

/ Setting Well Pressure #1  

beowulf

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Location
Central California Foothills
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Kubota L3410 HST, J Deere riding mower
Background: Our well was put in about 31 years ago. About 22gpm - well depth at 450' and pump set at about 430'. I am guessing it is a fairly standard set up. Bladder tank, relief valve, pressure switch, service disconnect. We replaced the pump about 10 years ago, otherwise no other attention has been needed except to file the pressure relief switch contacts from time to time (and once to clean out a nest of ants), and to change the service disconnect after I discovered to my great surprise it did not shut off the current (that is another story).

Anyway, because I recently had to file the pressure relief switch contacts twice within a month, I decided to inspect and then replace the very old pressure relief switch. I did that, and all again works well except that it seems the pressure to the house and far-out-lying bibs is a bit less. It seems to be shutting off at about 55 lbs.

So my questions: What pressure is recommended for this set up? (I vaguely recall it is supposed to have, or did originally have, a 40 to 60 lb low to high range range). Also, I think the new switch came set at an 80 lb shutoff before I monkeyed with it to turn it down - thinking that was too high - but maybe not?
Is the pressure setting related to the particular bladder tank we have, or independent of that?
I know you can set the low and high ends of the cycling, but don't recall which of the two spring set ups is for which and which way to turn to make those adjustments (CW or CCW). No instructions found with the new switch, and can't read the label inside the pressure switch cover. But I have played around with this to set pressures, but a quick reminder here would be helpful. Otherwise I will play around with the switch to figure it out.

Thanks for any help.
 
/ Setting Well Pressure #2  
I think most people run a 30(on)-50(off) psi range; or a 40-60psi range. Switches are commonly sold as one or the other. I run a 30-60 psi range just to limit the number of start/stops.

Ask yourself: Is the "low" pressure you notice in the house all the time (even when ballast tank is fully charged, highest pressure) or is it just before pump turns on (at its lowest pressure). This may determine what setting you want to adjust.

The big spring/nut adjusts BOTH the turn on and turn off pressure (i.e. the span stays constant, your just sliding the range (limits)). Turning CW raises the limits. (Example turning CW you can raise the cut on/off from 30/50 to 40/60; the span between the on/off stays at 20psi.)

The little spring/nut adjusts the span. Turning it CW increases the span (or thinking of it in another way: turning it CW raises ONLY the cut-off pressure. (Example: turning this CW you can raise the cut on/off from 30/50 to 30/60, the span is now 30 psi)

With no water pressure, the air in your ballast tank should have a precharge of 2 psi less than your cut-on pressure. (Example: If cut-on is set to 30 psi, your ballast tank air should be 28 psi. This is measureed / adjusted when the water pressure is zero.

Cut off pressure should always be at least 5 psi less than the pump dead head pressure.
 
/ Setting Well Pressure
  • Thread Starter
#3  
Coby, thank you for being so thorough and providing so much relevant information - explained perfectly. It is exactly what I needed. I am going to copy and print this and put it in my "well file" so I can refer to it in the future. I am not sure I would have ever figured it all out this precisely by trial and error. Thanks again.
 
/ Setting Well Pressure #4  
I think most people run a 30(on)-50(off) psi range; or a 40-60psi range. Switches are commonly sold as one or the other. I run a 30-60 psi range just to limit the number of start/stops.

Ask yourself: Is the "low" pressure you notice in the house all the time (even when ballast tank is fully charged, highest pressure) or is it just before pump turns on (at its lowest pressure). This may determine what setting you want to adjust.

The big spring/nut adjusts BOTH the turn on and turn off pressure (i.e. the span stays constant, your just sliding the range (limits)). Turning CW raises the limits. (Example turning CW you can raise the cut on/off from 30/50 to 40/60; the span between the on/off stays at 20psi.)

The little spring/nut adjusts the span. Turning it CW increases the span (or thinking of it in another way: turning it CW raises ONLY the cut-off pressure. (Example: turning this CW you can raise the cut on/off from 30/50 to 30/60, the span is now 30 psi)

With no water pressure, the air in your ballast tank should have a precharge of 2 psi less than your cut-on pressure. (Example: If cut-on is set to 30 psi, your ballast tank air should be 28 psi. This is measureed / adjusted when the water pressure is zero.

Cut off pressure should always be at least 5 psi less than the pump dead head pressure.

Pretty much what you said

Recommended ranges for residence:

30-50
40= 60

The 20 PSI difference is the optimum for pump performance and max tank delivery between on/off

Pressures over about 65 are not recommended for residence as that is hard on fixtures...of courswe that has been it as far back as I know. Modern fixtures probably wouldn't be botheree.

30-50 is what I run but doesn't run impulse sprinklers well down near shut off

To adjust pressure swith. Usual is for one tall screw and one short, Tall screw moves the range up/down, short I'm not sure about - might expand the range..

To set pre-charge, 2 psi below cut in: Shut off pump and run water until it quits running (lowest fixture), Add air to 2 psi below the cut-in.
 
/ Setting Well Pressure #5  
Pretty much what you said

Recommended ranges for residence:

30-50
40= 60

The 20 PSI difference is the optimum for pump performance and max tank delivery between on/off

Pressures over about 65 are not recommended for residence as that is hard on fixtures...of courswe that has been it as far back as I know. Modern fixtures probably wouldn't be botheree.

30-50 is what I run but doesn't run impulse sprinklers well down near shut off

To adjust pressure swith. Usual is for one tall screw and one short, Tall screw moves the range up/down, short I'm not sure about - might expand the range..

To set pre-charge, 2 psi below cut in: Shut off pump and run water until it quits running (lowest fixture), Add air to 2 psi below the cut-in.
I think one screw limits the upper (cutout) range, the other the lower (cutin) range.
 
/ Setting Well Pressure #7  
Coby, thank you for being so thorough and providing so much relevant information - explained perfectly. It is exactly what I needed. I am going to copy and print this and put it in my "well file" so I can refer to it in the future. I am not sure I would have ever figured it all out this precisely by trial and error. Thanks again.

Here is what you might do!
Copy the info, and tape the note (in permanent magic marker) to the side of your bladder tank.
Or....what I did: just wrote the info (in permanent magic marker) on the side of the bladder tank.
 
/ Setting Well Pressure #8  
I added a pressure gauge to the input of the hot water heater so I could see that everything was copacetic from inside the house:

P6240004.JPG
 
/ Setting Well Pressure #9  
I added a pressure gauge to the input of the hot water heater so I could see that everything was copacetic from inside the house:

View attachment 535214

Why do you want to know the inlet water pressure for your hot water tank?
Would you suspect it to be different than your cold water pressure throughout the building, or are you just trying to confirm what your overall house pressure is?
If you turn on any faucet, and the flow is weak, you will know that you have a pressure problem.
I can't see that reading the house inlet pressure is going to give you much useful pump/tank information.
 
/ Setting Well Pressure #10  
I can't see that reading the house inlet pressure is going to give you much useful pump/tank information.
The gauge is on the other end of the line from the tank at the well, that is outside a long way away. It shows me the pressure in the pressure tank and that everything is working right. If the pressure slowly drops when we aren't using water, there is a problem, like a leaking toilet flapper, fill valve or outside hydrant.

I also have a light at the well, that can be seen from the house, it comes on when the pump runs.
 
Last edited:
/ Setting Well Pressure #11  
The instructions to those pressure switches are confusing. If you don't mess with the small adjustment screw the difference between on and off will stay at 20 PSI. If you already messed with the little adjustment screw, just loosen it all the way. That will be about 17-20 PSI between on and off. Then make all your adjustments with the larger adjustment screw. Tightening it down will increase the pressure, lefty loosy will decrease the pressure setting. The most common setting is 40/60.

Filing points in the pressure switch is not good. There is a contact surface that you are destroying. I would get a new switch. Ants can get in a switch and mess up the contacts, but most of the time the contacts are burned from cycling on and off too much. When i see burned pressure switches or pressure switch band widths opened up to 30/60, I know the person is having problems with the pump cycling, which is what destroys most pumps.

The pump should never cycle while running sprinklers. Not only do the sprinklers not shoot out far enough at the lower end of the pressure cycle, but the pump is being cycled to death. A constant pressure valve like the Cycle Stop Valve would keep the pressure at a constant 50 PSI while running sprinklers or showers, instead of the pump continually cycling between 40 and 60. This not only keeps the spray pattern perfect but makes the pump, tank, pressure switch, and everything else last much longer.
 
/ Setting Well Pressure #12  
Filing points in the pressure switch is not good. There is a contact surface that you are destroying. I would get a new switch. Ants can get in a switch and mess up the contacts, but most of the time the contacts are burned from cycling on and off too much. When i see burned pressure switches or pressure switch band widths opened up to 30/60, I know the person is having problems with the pump cycling, which is what destroys most pumps.

Please verify that your bladder tank has not failed and is causing short cycling. If it's original to the system, it may no longer be functioning properly.
 
/ Setting Well Pressure #13  
I think one screw limits the upper (cutout) range, the other the lower (cutin) range.

Nope, tall moves the range but doesn't change it. I was the unpaid maintenance man for the community well for several years until I driledl my own to get out of that job.
 
/ Setting Well Pressure #15  
The instructions to those pressure switches are confusing. If you don't mess with the small adjustment screw the difference between on and off will stay at 20 PSI. If you already messed with the little adjustment screw, just loosen it all the way. That will be about 17-20 PSI between on and off. Then make all your adjustments with the larger adjustment screw. Tightening it down will increase the pressure, lefty loosy will decrease the pressure setting. The most common setting is 40/60.

Filing points in the pressure switch is not good. There is a contact surface that you are destroying. I would get a new switch. Ants can get in a switch and mess up the contacts, but most of the time the contacts are burned from cycling on and off too much. When i see burned pressure switches or pressure switch band widths opened up to 30/60, I know the person is having problems with the pump cycling, which is what destroys most pumps.

The pump should never cycle while running sprinklers. Not only do the sprinklers not shoot out far enough at the lower end of the pressure cycle, but the pump is being cycled to death. A constant pressure valve like the Cycle Stop Valve would keep the pressure at a constant 50 PSI while running sprinklers or showers, instead of the pump continually cycling between 40 and 60. This not only keeps the spray pattern perfect but makes the pump, tank, pressure switch, and everything else last much longer.

wI agree with the filing. Pressure switches are cheap, not worth tinkering with.
 
/ Setting Well Pressure #16  
The instructions to those pressure switches are confusing. If you don't mess with the small adjustment screw the difference between on and off will stay at 20 PSI. If you already messed with the little adjustment screw, just loosen it all the way. That will be about 17-20 PSI between on and off. Then make all your adjustments with the larger adjustment screw. Tightening it down will increase the pressure, lefty loosy will decrease the pressure setting. The most common setting is 40/60.

Filing points in the pressure switch is not good. There is a contact surface that you are destroying. I would get a new switch. Ants can get in a switch and mess up the contacts, but most of the time the contacts are burned from cycling on and off too much. When i see burned pressure switches or pressure switch band widths opened up to 30/60, I know the person is having problems with the pump cycling, which is what destroys most pumps.

The pump should never cycle while running sprinklers. Not only do the sprinklers not shoot out far enough at the lower end of the pressure cycle, but the pump is being cycled to death. A constant pressure valve like the Cycle Stop Valve would keep the pressure at a constant 50 PSI while running sprinklers or showers, instead of the pump continually cycling between 40 and 60. This not only keeps the spray pattern perfect but makes the pump, tank, pressure switch, and everything else last much longer.

Cycle Stop Valves are a recent thing. Wells ran for years and years with the old system and most systems out there still do. What kills pumps is 'short cycling' - not enough precharge air being he most common cause.
 
/ Setting Well Pressure #17  
The gauge is on the other end of the line from the tank at the well, that is outside a long way away. It shows me the pressure in the tank and that everything is working right. If the pressure slowly drops when we aren't using water, there is a problem, like a leaking toilet flapper, fill valve or outside hydrant.

I also have a light at the well, that can be seen from the house, it comes on when the pump runs.

I have a light.....in the house ..... that tells me when the pump is running.
 
/ Setting Well Pressure #18  
What kills pumps is 'short cycling'.

Yep and that is exactly what a Cycle Stop Valves keeps from happening, hence the name. And your right the old pressure tank only systems are very reliable, as long as you don't run small amounts of water that cause the pump to cycle. And now that there is a way to stop the pump from cycling no matter what you do, pressure tank systems are even more reliable. And I have been using them for 25 years, there is nothing recent about them, or me either anymore. :)
 
/ Setting Well Pressure
  • Thread Starter
#19  
OP - update:
Confirmed that my pressure switch was set to a 40 start-60 cut off range. But still had some unexplained recycling - i.e., no water running yet pump was recycling when it should not have done so. I thought it might be that the check valve was letting water back into the well but then learned that there is a second check switch down line in the well. So, maybe that is an issue, maybe not.

Then turned power off and using the bib at the pump, completely drained the bladder tank and checked the pressure at the tank - only about 7 - 10 lbs. Hooked up a compressor and recharged the air in the pressure tank to 37. Closed the bib, turned the power on and it started up- filling the tank and then shut off at 60. It now, with no water being drawn down, stayed at 60, i.e., no more of the recycling I saw before.

Thanks to the posts here warning me about the risk to the pump with recycling, as that caused me to go back and try to figure it out. So far, all is well, but I have no idea exactly why the lack of air in the tank would cause recycling when there was no water being drawn down. If we were using water, even with a problem bladder, I assume the pump would give us water to the house but would just keep recycling. Not understanding the dynamics of all this bothers me so will likely keep thinking about it.
 
/ Setting Well Pressure
  • Thread Starter
#20  

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