We're having a bit of trouble with our well and water pressure, and I'm hoping you all might be willing to help us troubleshoot.

This is a residential home with a well and a tank with a 40/60 pressure switch. The home is around 20 years old, the pressure switch and gauge have been replaced in the past, and I believe the well pump and pressure tank have never been replaced. Tank pressure is at 38 psi. No water is running in the house. The pressure switch engages at around 40 psi, runs for about 12 seconds until it reaches 60 psi, then disengages. Over about 22 seconds, the pressure drops from 60 psi to 40 psi, and the process repeats. This has been happening for a couple of weeks now and would, at times, drop completely to 0 psi, though that hasn't been happening the past few days. Shutting off the water to the house does not change this cycle. (We have been cutting off the pump when water is not in use to reduce load on the pump.)

Pressure tank and switch

We have had two people out to troubleshoot the system (that's two opinions, and I guess posting here would be a third). Both folks watched the cycle, shut off the water to the house to rule out anything there, then went out to the well head and listened for water rushing back in. Neither heard anything, so they both concluded that there must be a break in the line between the well and the house. Does that sound right? Should we expect them to do any more troubleshooting (like pulling the pump) before having the line replaced?

The two things that give me pause are the following. I believe I have noticed surprisingly warm water coming from an outdoor spigot, even though the weather is cool here now (though I don't know what that might indicate). And, we haven't noticed any particularly wet spots in the yard, and I guess I'm surprised that the pressure could drop so quickly without leaving such evidence of a rupture.

Finally, we're interested in exploring our options and, of course, reducing cost as much as possible. Are there straightforward ways of locating the line between the well and the house? Would finding the rupture just include looking for wet areas in the yard? If found, is it reasonable to just dig up the area around the rupture and patch it? Failing all of that, if we have a professional run a new line, how much should we expect to pay in Virginia (assuming the well head is about 75 feet from the house)?

We appreciate any thoughts you all might be willing to provide.


Do you have a valve on the line from the well that is before the pressure tank? If so, try this test.

Wait for the pump to run. When turns off, shut the valve. If the pressure tank holds, then the problem is on the well side of that valve. If it doesn't then you have a big leak in the house plumbing somewhere. (Imagine a broken line in a crawl space...)

Next check depends on the well hookup.

Most 20 year old houses have a pitless adapter. Take the cap off the well. Often there is either a iron pipe even with the top of the casing. Sometimes you will have to bring your own. The top of the adapter is threaded, I think for 1" ID iron pipe. You will want sufficient length of pipe to reach to the adapter and also a T connector and a couple of 6" nipples. Put the T on one end of the pipe, and the nipples in the side branches. This prevents dropping the whole pipe string down the well.

Before you start, but after you have taken the cover off do a cycle of the well. Listen for water escaping around the pitless adapter. Listen also for water from a cracked riser pipe. You may be able to shine a flashlight down the well if you have a really bright one.

Turn off power to the well.

Screw the other end of the T into the pitless adapter.

There will also be a cable, usually about 3/32 or 1/8 This connects to the spring latch on the adapter. Often there is a safety rope too. This is connected to the pump, and is used to rescue the pump if the riser pipe breaks. Tie it to something solid.

Drill a hole in a a couple feet of 2x6, corresponding to the outer diameter of the riser pipe. If you have no clue, drill holes of 1" 1.25" and 1.5" Make the holes about 4-5 inches apart. Not critical. Run the board through a saw so that you now have half holes. Cut a few scraps of wood.

Get help for this next step. With the T bar pipe in the adapter, pull the latch, and pull up the pipe until the adapter is above the top of the well. Put the two half boards on either side of the riser, and attach the scraps to the board with screws. This will keep the pipe from dropping back into the well.

Open a tap in the house so that the pressure tank is below the cutin pressure.

Now turn on the well. Water should gush out of the adapter. As soon as you have good flow turn it off. Should only be a few seconds. Walkie talkies or cell phones make coordination easier.

Wait a while. If your pump was cycling on a 30 second round, waiting a minute is lots.

Put your hand firmly over the opening in the pitless adapter and turn the pump on again. If the water dropped in the well, there will be a slug of air in the riser pipe, you will feel it push against your hand before the water comes out. 1"line runs about 30 feet per gallon of water. If your well is 100 feet to the top of the water, you will have about 3 seconds of air before the water hits your hand.

If the water is immediate, (only a couple of inches of air in the top of the adapter) then the well is fine.

If there was a slug of air, then the foot valve in the well needs replacing. Or you have a big crack in the riser pipe. Pull the entire riser string, replace the foot valve or the riser pipe and put everything back together.

If there was no slug of air, then you have a problem between the well and the pressure tank.

Note that a failed gasket between the pitless adapter and its fitting in the casing would also account for this. Replace the gasket just 'cause.


Wow! This actually helped someone.

If you replace a well pump, and you are using more than residential quantities of water (You have a tap running for more than an hour a day) give thought to a VFD drive pump. VFD pumps use a 3 phase motor. The controller box turns residential single phase into 3phase, and also adjusts the frequency. This allows the pump to start slowly, which is easier on the pump and on the well. It can also be set to approach the cutoff pressure slowly, by reducing rpm. The one I looked at for my well was rated at 10 gpm, but could self throttle down to 1 gpm. This means that the pump doesn't cycle as often, which keeps the water level in the well bore more constant. Rising and falling water levels tend to wash sand and mud out of the side walls.

  • Sherwood, please excuse my rather late reply. Your troubleshooting steps were enormously helpful and got us to understand that the issue was, in fact, in the well. Because the house is nearly 20 years old and we had the pump out to replace the foot valve anyway, we replaced the pump too. We did this all at a fraction of the cost quoted by two companies (both of which failed to accurately diagnose the problem). So... thank you! – cjg Nov 19 '19 at 18:50
  • You're welcome. I hope you kept the old pump. It's nice to have a spare you can put in on a long weekend. (You just try to get a well contractor on a weekend...) – Sherwood Botsford Nov 20 '19 at 11:09
  • We did keep the old pump, as I had some ideas about how to put it to good use. Having it around as a spare is a great thought, and something I hadn't considered (though I'm hoping it would have occurred to me if we experienced another failure). In any case, thanks again! – cjg Nov 21 '19 at 14:06

Since you shut off the outlet to the house and it drains down your foot valve has probably failed or is getting sticky. I have seen this more often on jet pumps where the foot gets stuck open slightly or the jet has corroded. If a submersible I have seen the line crack several times , some cut corners and don’t install a torque arrestor each time the pump kicks on the motor jerks and over time cracks the line. These are the 2 types of leak back problems I have seen with the output isolated. Since it is intermittent I would run a couple outside faucets full open for a couple of hours to flush the well out sediment may be building and causing it to stick, note after a hard draw down the water may be brown when you allow it to refill, this is normal just run until clear, this shows that you did disturb the silt and may clear the problem but be prepared if a jet the foot and jet it self may be close to need replacement, if a submersible the pump and possibly the line may need replacement.

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