Pressure tank gauge drops to zero before pump cuts on

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Stude60

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My problem started after I changed pressure tanks, no problems prior to change. This is what happens.
When the gauge pressure drops from 60 to 40 psi, right before the pump starts the gauge pressure drops to zero. In a few seconds the gauge starts to climb and shuts the pump off @ 60psi. If you are using water when the gauge hits 40, the water stops flowing for a second or so. The pressure tank is charged at 38 psi. The gauges are new. What I have done and observed. I turned power off to pump. Connect hose to bottom tank drain. As I drained the water and watched the gauge pressure drop, when the gauge pressure hit 40 psi it fell immediately to zero. Turned power back on and pump started and pumped to 60 psi and shut off. At this point pressure holds steady, no drop. I am pushing water out slowly through a hose starting at 60 psi and it flows steady until it hits 40 psi, then it is instantly no more flow and straight to zero. If it was still water in the bladder @ 40 psi would it not continue a slow drop on the gauge. Anyone have any ideas ?
 

Reach4

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Jet pump? If so, move the air precharge to 35 or 36.
 

Reach4

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With the water pressure 40 or above, the air pressure should be very close to the water pressure. If it is not, the calibration on your air pressure gauge and/or water pressure gauge is off.

Another possibility is that your pressure switch is slow to respond to low pressure by turning on the pump. That could be due to a clogged nipple or pressure switch.
 
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Stude60

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Thanks Reach4. Tomorrow I will check air pressure against gauge pressure reading. I will remove pressure switch and check nipple and pressure switch for clogging . I will post my findings.
 

Wondering

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Thanks Reach4. Tomorrow I will check air pressure against gauge pressure reading. I will remove pressure switch and check nipple and pressure switch for clogging . I will post my findings.
I have a 40/60 switch also. I just run my tanks with 35 PSI. I figure if something is a little off you have more allowance with 35 plus it's only 3 PSI from the recommended 38 psi. No problems so far.
 

Stude60

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It turned out to be a slow responding pressure switch. Thanks for all the help.
 

Stude60

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Yes, the nipple was packed full of sediment/rust. I ended up running a drill bit through the nipple.
 

25td419

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Now that makes sense to me. Was the pressure switch mounted in the upright position? That is usually best when you have sediment.[/QUOTE
I am having same problem and replaced switch and pressure still drops to 0. Where do I find the nipple to see if it’s clogged
 

Reach4

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I am having same problem and replaced switch and pressure still drops to 0. Where do I find the nipple to see if it’s clogged
The little pipe that connects to the pressure switch is called a nipple. That is usually "1/4 inch NTP" (MIP) , which is 0.54 inches OD.
brass-everbilt-brass-fittings-802409-64_145.jpg


It is best to have that made from brass or stainless steel to avoid rusting.

https://www.osha.gov/SLTC/etools/oilandgas/glossary_of_terms/glossary_of_terms_n.html says

nipple
n: a tubular pipe fitting threaded on both ends used for making connections between pipe joints and other tools.​
 

25td419

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When you replace the pressure switch just ream out or replace the nipple that it is screwed onto.
Thanks for reply. The first time we replaced it we didn’t empty bladder tank and water sprayed in the air. Would this indicate it’s not clogged?
 

Reach4

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Thanks for reply. The first time we replaced it we didn’t empty bladder tank and water sprayed in the air. Would this indicate it’s not clogged?
I think it indicates the nipple was not clogged after the spraying incident.

Speaking of pressure tanks, you should flush out sediment on periodically. The period varies. Annually is good for most wells, but wells with much sediment, adjust the period based on what you see.

To flush the sediment,
  1. Turn off the power to the pump. Run the pressure tank empty using the drain valve near the input of the pressure tank. Usually you want to use a hose to direct water and sediment to a good place. Note colors and solids coming out toward the end of the flow.
  2. Close the drain valve, Turn the power to the pump back on for maybe 6 seconds. Turn the power back off. Again drain the water and sediment.
  3. Repeat #2 until no sediment comes out.
  4. Check/adjust the air precharge with the water pressure zero. Usually you want 2 psi below the actual pressure switch cut-on pressure for a submersible pump, and 5 psi (or whatever it takes to avoid a pressure stutter when the pump turns on).
  5. Close the drain valve, and turn the power to pump back on.
 

25td419

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I think it indicates the nipple was not clogged after the spraying incident.

Speaking of pressure tanks, you should flush out sediment on periodically. The period varies. Annually is good for most wells, but wells with much sediment, adjust the period based on what you see.

To flush the sediment,
  1. Turn off the power to the pump. Run the pressure tank empty using the drain valve near the input of the pressure tank. Usually you want to use a hose to direct water and sediment to a good place. Note colors and solids coming out toward the end of the flow.
  2. Close the drain valve, Turn the power to the pump back on for maybe 6 seconds. Turn the power back off. Again drain the water and sediment.
  3. Repeat #2 until no sediment comes out.
  4. Check/adjust the air precharge with the water pressure zero. Usually you want 2 psi below the actual pressure switch cut-on pressure for a submersible pump, and 5 psi (or whatever it takes to avoid a pressure stutter when the pump turns on).
  5. Close the drain valve, and turn the power to pump back on.
I will do this when I get back. Do you think that could cause problem. I can shower and won’t run out or do a load of laundry. But if I run laundry then hop in shower the water cuts off to zero for a minute then kicks back on
 

25td419

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I think it indicates the nipple was not clogged after the spraying incident.

Speaking of pressure tanks, you should flush out sediment on periodically. The period varies. Annually is good for most wells, but wells with much sediment, adjust the period based on what you see.

To flush the sediment,
  1. Turn off the power to the pump. Run the pressure tank empty using the drain valve near the input of the pressure tank. Usually you want to use a hose to direct water and sediment to a good place. Note colors and solids coming out toward the end of the flow.
  2. Close the drain valve, Turn the power to the pump back on for maybe 6 seconds. Turn the power back off. Again drain the water and sediment.
  3. Repeat #2 until no sediment comes out.
  4. Check/adjust the air precharge with the water pressure zero. Usually you want 2 psi below the actual pressure switch cut-on pressure for a submersible pump, and 5 psi (or whatever it takes to avoid a pressure stutter when the pump turns on).
  5. Close the drain valve, and turn the power to pump back on.
I will do this when I get back. Do you think that could cause problem. I can shower and won’t run out or do a load of laundry. But if I run laundry then hop in shower the water cuts off to zero for a minute then kicks back on
Check/adjust the air precharge with the water pressure zero. Usually you want 2 psi below the actual pressure switch cut-on pressure for a submersible pump, and 5 psi (or whatever it takes to avoid a pressure stutter when the pump turns on).
Does this mean with no water in tank
 

Reach4

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I will do this when I get back. Do you think that could cause problem. I can shower and won’t run out or do a load of laundry. But if I run laundry then hop in shower the water cuts off to zero for a minute then kicks back on
That symptom could be various things. To know what to blame, you would want to know whether the pressure switch was sending power to the pump, and the pump was not delivering water, or if the pressure switch had a delayed closing (turn-on).

If what you describe is predictable, I would suspect that either the well is running out of water, or the pump motor is shutting down due to overheating.

Where is your pump? Down the well (submersible) or up top?
Does this mean with no water in tank
Yes. Zero water pressure results in no water in the tank, unless the tank has failed.
 
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