Problem with a leak in my well water system - help me diagnose?

[jennigrey]

Okay, tell me if I am barking up the wrong tree here.

Here are the details of the layout of our water system:

First of all, we live in a mobile home. The mobile home itself is level, but the site is not. Thus, we have about 2' of clearance under the front of the mobile home and about 4.5' of clearance under the back of the mobile home.

The pressure tank, pressure switch and pressure gauge are under the mobile home, at the back, where there's enough clearance for the tank.

We have a well, of the type where the pump is in the well casing. The wellhead is downslope from the mobile home, pressure tank, etc.

Half-way between the wellhead and the pressure tank, we have a frost-free hydrant where we hook up garden hoses to fill troughs, etc. All other points of use for the water system are inside the mobile home.

The pipe from the well, to the hydrant, to the pressure tank is underground. It comes up from underground at the pressure tank.

The pipe from the pressure tank to the mobile home is all exposed/visible and wrapped in insulation.


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Somewhere, I have a leak. The pressure switch in my other thread burned out because the pump is kicking on less than every five minutes. If I don't figure out where the leak is, my pump is sure to follow.

Yesterday I watched the pressure gauge. The pump kicks on at 20psi and turns off at 40psi. This isn't right. Either the switch needs to be adjusted (it's supposed to be a 40/60) or the gauge isn't reading accurately. Anyhow, when the pump kicks off at 40psi I can watch the needle drop till it gets to 20psi, at which point the pump kicks on again.

So! A leak somewhere. Here's where it gets interesting.

When I went to replace the pressure switch the other day, I first needed to drain the pressure tank so water didn't come spewing out of the little pipe that the pressure switch threads on top of. I hooked up a short length of hose and opened the drain valve.

NOTHING CAME OUT.

Nothing. The pressure tank was completely empty of water and - furthermore - all the water that should have been in the lines in the house above me was also all gone.

There is no water leak under the mobile home. The ground under the mobile home is covered in plastic so any water leaks from the house lines would show up on the plastic. I can visually trace the PVC pipe from the pressure tank to where it disappears up into the house. No leaks there.

That means that the leak is somewhere between the pressure tank and the well, right? Either in the pipe that is buried or in the well casing itself.

What is in the well casing that could be leaking? A friend of mine thought that if it was the foot valve that is faulty, that I would have lost my prime when the pressure switch went out. However, I think this only applies to wells where the pump is above the water line and wouldn't apply to our submerged pump.

I can find no soggy spots anywhere that would indicate a break in the buried pipe between the wellhead and the pressure tank, so I am leaning toward there being a problem somewhere inside the well casing.

Is this a reasonable assumption?

Where would the foot valve be in relation to the pump? Would all the pipe and the pump have to be pulled to replace the foot valve?

[tinknal]

Sounds to me like either your pressure tank is bad, or waterlogged. There should be an air fitting on your pressure tank where you can refill it with air. Not sure how much air to put in. If this doesn't fix it then you have a leaky tank.

[jennigrey]

No evidence of leaks on the ground around the pressure tank itself. It sits on a small cement pad under the mobile home.

I think I read somewhere that, with the tank drained and the breaker to the well off, the tank should read 2psi at the valve stem.

I can check that in a couple of days. We're still getting caught up on all the chores that require water, after having no water for 11 days - so I'm not excited about shutting it off again just yet!

[jennigrey]

Would a bad pressure tank allow our water to go back down the well? I thought there was a one-way valve to prevent water -once raised- from going back down the well. I thought that was what the foot valve was about.

There is nowhere that water could be leaving the system aboveground. I would certainly see it.

[Harry Chickpea]

First, a compliment. That is one of the BEST descriptions of a problem I have seen on the internet. Precise, detailed, logical.

Your assumption that the issue is downstream of your surface plumbing seems to be spot on.

At this point, you could verify this if you had a T and drain valve at the wellhead, but you can do the same type of test by opening the hydrant. (Do you see why your description is so important now?)

If no water comes out of the hydrant, you absolutely have determined the problem to be in the well.

Yes, the pump and piping will need to be pulled. There are ways of doing that using a tripod and a pair of clamps and a lever arm, or just by brute strength of a number of guys, and some sort of sling for the pipe to allow them to rest between pulls.

The foot valve is a possibility still. In some way, the water is draining back, either through a leak, loose connector, bad pump, or the foot valve.

Again, I am impressed with the way you described things.


Edit to add - there is also a small possibility that your well is running dry. Measure the water level before pulling the pump by using a sounding line with a bit of wood attached, then measure where the pump is in relation to the surface by measuring the length of the pipe to it.

[agmantoo]

Your pump being inside the casing is a submersible pump. Your leak problem is from 1 of 2 sources. The check valve for the pump is broken or stuck or the water line from the pump line (pipe leading from the pump to the surface) itself has a hole worn in the side of the line as a result of the line rubbing against the inside of the casing. Since the pump is shutting off at 40 PSI and on at 20 PSI I am of the opinion the pressure switch is OK and that the pressure switch is actually a 20/40 PSI. The size of the hole in the line from the pump or the amount of leak at the check valve cannot be verified without pulling the line and pump. However, you can for now fix the situation by installing a check valve above ground at the point of discharge of the well water/supply pipe to the pressure tank.

[Fire-Man]

Originally Posted by jennigrey

Here's where it gets interesting.

When I went to replace the pressure switch the other day, I first needed to drain the pressure tank so water didn't come spewing out of the little pipe that the pressure switch threads on top of. I hooked up a short length of hose and opened the drain valve.

NOTHING CAME OUT.

Nothing. The pressure tank was completely empty of water and - furthermore - all the water that should have been in the lines in the house above me was also all gone.

I might have missed it but I am thinking you got a bladder tank so my comments will be for that type of tank.

Sounds Like your tank is water logged. When you took the line loose if you would have open a spiket in the house it probably would have slowly drained out the tank. Try this. With your pressure built up on the pump/tank, get someone to open a spiket or flush the commode. I bet the pump will come on in seconds and will cut off in seconds after the spiket is closed----that would mean your tank is water logged. If the tank is water logged, it is most probably bad and will need to be replaced, But you can pressurize it and see if it holds up or not. What you are seeing---tank pressure dropping can be as simple as a slow leaking tank on your commode---if the water tank is water logged.

Originally Posted by jennigrey

I think I read somewhere that, with the tank drained and the breaker to the well off, the tank should read 2psi at the valve stem.

This pressure should be a couple pounds below your cut in pressure-----on your set-up that would be 15 to 18lbs being your pump comes on at 20lbs. Once you get this straighten out, you can increase your pressure back to 40/60 with 35 to 38lbs of tank pressure "drained".

[jwal10]

Is there a valve in the line from the wellhead to the pressure tank? Let the tank fill and shut this valve off. Is there a valve between the tank and the mobile? turn it off. Does the pressure gauge hold pressure? The valve at the well is not a foot valve, it is a check valve. It keeps the water from draining back through the pump when the pump shuts off. They do go bad. You have to be careful as the pressure is regulated at the pressure switch, so you don't want to close a valve before the switch and run the pump, it will build excess pressure in the line. If you can isolate with the 3 valves you can determine where the leak is, in the well, from the well to the tank, from the tank to the mobile or in the mobile itself with a pressure gauge on a faucet in the mobile....James

[hillbillytn]

Pipe down the well cracked. Maybe fitting at the pump.

[farmrbrown]

Harry in post #5 gave the advice on how to check for a problem between your well and your home.
am1too, gave you a possible solution if the pipe going down to the casing isn't cracked.
If that's where the leak is, get a tractor with a bucket, some friends and some beer and have a well pulling party this weekend. They're aren't that much fun, but they don't last all day either......

One last thing to check before you start. It's simple to do. Take a tire gauge and check the pressure tank. Somewhere on it is the same kind of valve that your tires have.
For a 40/60 system, it should have 38 lbs. of air in it - 2 lbs. less than the cut on pressure.

[biggkidd]

I've run into this several times 9 times out of 10 its the foot valve going / gone bad. Thats the good news the bad news is lots of times the impeller has broken up and a piece or pieces of it are lodged in the foot valve. How deep is your well? Most wells under 150 ft can have the pump hauled by hand by one man. Hope this helps.

Larry
A World Away

Edit to add: You will need a propane torch to heat the black poly water line off the pump after you loosen the clamp. Don't cut / break the wires unless you find you have to replace the pump. Also most newer well pumps have the foot valve made in the pump housing.

[rambler]

There is one sneaky leak that most people never notice - a toilet leak.

They can bleed off a lot of water and not be noticed.

Food dye in the tank, or shutting off the valve to the toilets, would eliminate them.

Otherwise, I would suspect the check valve as you do, and yup, pull all the pipe up to get to it.

Other good ideas here too, hole in pipe, etc.

You can have more than one problem......

Things I've run into, that little pipe to the gauge and the pressure switch fills up with gunk and gives erratic results. Pump doesn't come on, doesnt shut off....

Pressure gauges go bad in a year or 2 for me, kinda sad the lack of quality...

Paul

Paul

[davel745]

Originally Posted by agmantoo

Your pump being inside the casing is a submersible pump. Your leak problem is from 1 of 2 sources. The check valve for the pump is broken or stuck or the water line from the pump line (pipe leading from the pump to the surface) itself has a hole worn in the side of the line as a result of the line rubbing against the inside of the casing. Since the pump is shutting off at 40 PSI and on at 20 PSI I am of the opinion the pressure switch is OK and that the pressure switch is actually a 20/40 PSI. The size of the hole in the line from the pump or the amount of leak at the check valve cannot be verified without pulling the line and pump. However, you can for now fix the situation by installing a check valve above ground at the point of discharge of the well water/supply pipe to the pressure tank.

I recommend you do this. it will buy you some time to plan for the repair and it will tell you if the leak is in the well bore or in the line to the house. You could in fact run the well this way for quite awhile if necessary.

[GunMonkeyIntl]

Originally Posted by jennigrey

Yesterday I watched the pressure gauge. The pump kicks on at 20psi and turns off at 40psi. This isn't right. Either the switch needs to be adjusted (it's supposed to be a 40/60) or the gauge isn't reading accurately. Anyhow, when the pump kicks off at 40psi I can watch the needle drop till it gets to 20psi, at which point the pump kicks on again....

It's possible that your in-line gauge is bad, but you can easily check/confirm it by checking the shrader valve at the top of the tank with a common tire pressure gauge. The pressure at the valve on the top of the tank, and the pressure at the inline gauge should be the same. If they are not, then you know you have a bad gauge.

The switches, when you buy them new, are usually pre-adjusted to the specs listed (40/60, 30/50, 20/40). It's possible that your new one was adjusted wrong, but not likely.

Originally Posted by jennigrey

....I think I read somewhere that, with the tank drained and the breaker to the well off, the tank should read 2psi at the valve stem.

Your tank, when empty of water, should be 2 psi below cut out pressure. So, if you're installing a 40/60 switch, then your first step is to shut off the breaker, drain the tank, and use an air compressor or bicycle pump to pressurize the tank to 38 psi (28 psi for a 30/50, 18 psi for a 20/40). Since pressure tanks do leak down with time, it is considered required routine maintenance to drain the tank and repressurize it from time to time.


I'm guessing that your pump is OK, since the tank is building up to cut-off pressure before leaking down.

The toilet, as pointed out above, is a likely candidate. Fortunately, your toilets should have local cut-off valves, so you can turn them off for a couple hours and see if it changes the behavior of the system.

The one possible source of the leak that I haven't seen mentioned is the line from the pressure tank out to the yard hydrant. You described the system as having a line that comes from the well to the hydrant and then onward to the pressure tank, but I don't think this is correct. I'm near certain that your line comes from the well directly in to the pressure tank, and then back out to the hydrant.

Since your pressure switch is what tells the well pump when to turn on and off, if the hydrant was plumbed in between the well and the pressure tank, opening your hydrant would only provide water until the system lost prime. Since you wouldn't be drawing pressure off the pressure tank, the well pump wouldn't know to turn on. If you study your plumbing, I'm sure you will find a small feed line going back into the ground and running out in the direction of your hydrant.

Most hydrants are supposed to be frost proofed but, just like the utility spigots many of us have around the outside of our houses, they do freeze up from time to time, develop internal cracks, and start leaking. If you can't find the leak anywhere else, you can test if your hydrant is the culprit by putting in a shut-off valve. Find the line feeding back out to it, hacksaw out a small section of the line, and fit in an on/off valve. Then you can test it for leaks just like you would your toilet - turn it off and watch the pressure in your system.

[agmantoo]

Put some food dye in the water closet and see if the water in the bowl changes color. If it doesn't then try post #6

[rambler]

The check valve might sound intimidating, but Menards or any big box store has them for $15 or less, need to size to your pipe size, and get a little wiggle room and coupler to put it in. Not that difficult.

Paul

[jennigrey]

A storm blew in so I'm working on other things just now. The well and pump will have to wait for a few more days.

THANK YOU so much for all of the help, advice, suggestions and expertise. This board is just the best.

As an aside: no leak at the commode. The kitchen faucet has a slow leak... one drip every 10 seconds or so. Can't remember if I saw any shutoff valves either side of the pressure tank. I'm pretty sure that the hydrant *is* inline between the wellhead and the pressure tank. The pressure tank should be able to send water "downstream" to the hydrant just as readily as "upstream" to the house, I should think. Everything in the system, between the point of use and the foot valve in the well, should be pressurized at whatever is reading on the gauge, I think.

[fishhead]

Here's a question.

If the foot valve leaks (underwater) wouldn't the water still stay in the plumbing as long as no faucets were opened? Kind of like turning a pop bottle upside down with the lid partially open.

[Harry Chickpea]

Originally Posted by fishhead

Here's a question.

If the foot valve leaks (underwater) wouldn't the water still stay in the plumbing as long as no faucets were opened? Kind of like turning a pop bottle upside down with the lid partially open.

Nope. For the same reason you cannot use a suction pump to pump water higher than 32 feet. The draining water has no problem creating a vacuum. Air pressure is what keeps a column of water in an inverted pop bottle. Make the bottle too tall and the weight of the column of water is greater than the pressure of the air resisting the effect of gravity on it. The concept is easier to understand if you start off thinking of a thousand foot tall standpipe with a leak at the bottom. That water will shoot out under pressure.

[davel745]

Originally Posted by fishhead

Here's a question.

If the foot valve leaks (underwater) wouldn't the water still stay in the plumbing as long as no faucets were opened? Kind of like turning a pop bottle upside down with the lid partially open.

I doesn't work that way as the pressure tank will let the water go back down the pipe.