We have a well that is used for lawn irrigation and our geothermal A/C unit. It was replaced in 1998 (new well, submersible pump, lines, tank, etc.) Last week we noticed the tank was losing pressure and discovered fittings on the pump had corroded. The tank appears fine (I can hear the bladder expanding as it fills). We decided to replace the pump (given its age) and thought we were done. Not so. The tank is losing somewhere around 8psi per day (and we know the pump isn't running during that time, we cut the power to the pump just to be sure.) We've called the company who installed the new pump and are waiting for them to visit and determine that their work was done properly (we have no reason to doubt them, they are a well established company that has been in business for many years). We just want the problem solved. So, the question is: How long should a water well tank hold pressure? Thanks!

Did you shut the valve at the well head to the house service to isolate the leak? This could be a leak in the house or a piece of trash could have got in the check valve. Try to pin point the leak and get back with the results.
Good luck, Tom

It should hold pressure for a very long time is the answer... DAYS certainly, weeks, maybe even months. A leak is a leak... and there should be no leaks. Now to find it. I'd follow speedball1's advice to start isolating it.

Did you shut the valve at the well head to the house service to isolate the leak? This could be a leak in the house or a piece of trash could have got in the check valve. Try to pin point the leak and get back with the results.
good luck, Tom

Thanks for the fast replies. Lines are shut off within the house (after the tank). There is no other shutoff before the tank, so, I can't isolate the tank as the problem. I do know it is properly pressurized (within 2 psi of the cutoff pressure).

We do have some sinkholes in the yard in the area where the line was run. The well guy told me if there were leaks we'd see water. I kind of doubt that, especially since I don't see how a slow leak would have enough pressure to defy gravity and go UP several feet, but it could explain the sinkhole, no?

-kj-


I should clarify... we have one small sinkhole we've had for years (it's never progressed beyond a small dent in the ground) and one other I recently discovered.

OK Kevin, Let's nail this down. When you shut the house shut off does the pressure hold or fall?
Losing 8 pounds a day isn't much so the leak isn't a major one.
You must first find out if the leak's in the pressure line from the pump to the well head.
Is there a valve at the well head you could shut off to check? I keep coming back to those sink holes near the service. How deep is then service burred? Can you dig down and check? Back to you, Tom

Hi Tom, thanks for the speedy info. This place is awesome.

The drop off in pressure we are seeing is with the house shut off completely. So the leak must be somewhere between the tank and the well. I do not know if there is a valve at the well head but I can ask the person who did the install, he is calling me back sometime today.

The service is supposedly buried 'a few feet deep.' If I were to dig anywhere, it would be in the area of the second sinkhole, where I am almost positive there is an "L" joint because it has to turn to reach the house. The wife probably isn't going to like the idea of me doing recreational excavation, but the next question is, if the line is leaking at that point, how hard or expensive is it to repair?

-kj-

the leak must be somewhere between the tank and the well. Or between the tank and the house. Since you've shut down the house and still lose pressure you've completed the first step. Move on to the house service. You can save digging up the sink holes in you install a shut off valve at the well head. Let me know your next move. Good luck, b Tom

Just got off the phone with the guy who did the well. He says the pitless adapter may be mating up with a piece that is steel and not brass. The old pump had a mix of steel and brass parts, the steel part is what was leaking and was replaced. He recommended digging out around the PVC casing (carefully) until I get to the area where the pitless adapter is and chances are I'd see the leak if there was one. As for the other possible area of a leak, I was mistaken, there should be no "L" in the line since it's poly pipe (not rigid) but there is a chance they had to splice it (I need to measure and see if the spot in question is 100' from the well, if so, use of 100' pipe sections would explain it.) So I guess I'll be spending Father's Day with a shovel in my hand, lol...

Before I started digging up 100' of pipe, I'd install a cutoff a foot or two from the tank (easy to do), then see if pressure continued to fall. If it holds, then you can start digging. If it falls, then you look towards the well, not the house. As you can imagine, to have that cutoff valve in place would be a good thing for the future anyway.


I see your point but I wasn't planning on digging up the entire line, just down a bit at the well head and try to get low enough to see the pitless adapter and determine if it is leaking. Diggin' in the dirt is even easier that installing a shutoff (which is beyond my skills, honestly!) I will keep everyone posted!


Understood. Best wishes. The good news is this: You are not losing much water at only 8# a day. You don't have to get in "emergency gear" at this point.

Thanks. Exactly. It's just for the A/C and lawn anyway, so, not mission critical (as long as it doesn't get too hot, lol)

An interesting development... after losing 8 psi per day the rate of loss slowed considerably... at 7am Wednesday the tank was at 46 psi (having dropped from 54 psi 24 hours earlier)... at 7pm Wednesday it was at 44 psi and at 7am Thursday it was 40 psi. Anyone ever seen anything like that before? Planning to get the shovel out over the weekend and start the exploratory digging...

One thought. You might want to make sure the air valve on top of the bladder tank is not leaking.

Great idea - but it's fine - lobbed a nice drop of spit on it, nary a bubble. It's tight. Thanks!

Lines are shut off within the house (after the tank). There is no other shutoff before the tank, so, I can't isolate the tank as the problem.
You can save yourself a lot of digging if you'll only cut into the water service at the well head and install a shut off valve and a pressure gage on the service line side. . Before you go half cocked in all directions you MUST isolate the problem and know what direction to take.
When you install the stop and gage run the pump up to pressure and shut the house off at the house stop. If you continue to loose pressure leave the house shut off and close off the stop at the well head. If the pressure continues to fall the problem's in the water service however if the pressure stays steady you have a leak in the line coming from the pump to the surface. I think your problem will be found in the water service but we have to look at the worst case scenarios so I'd fell a lot better if the line from the pump to the well head were eliminated. **OR**
You can break out the shovel. Good luck, Tom

Kevin, I know you've already commented on this idea, but Speedball's got a really good point. That cutoff valve would be valuable. If you dig to the Pitless adapter and find it to be good, then get back with us. Putting a stop valve at the pressure tank would be relatively simple and very useful.

Kevin, I know you've already commented on this idea, but Speedball's got a really good point. That cutoff valve would be valuable. If you dig to the Pitless adapter and find it to be good, then get back with us. Putting a stop valve at the pressure tank would be relatively simple and very useful.

Absolutely. Will do. Thanks!

Let us know the results. Good luck, Tom