Our well feeds a 119 gallon Amtrol (?) pressure tank under the house. If it’s real quiet you can hear the solenoid click and a slight hum as water runs into the tank, so I sometimes know when it’s filling. Once in a while, it will cycle first thing in the morning shortly after the first flush or run of the tap. I’m not sure why this is…. seems like it should require many gallons drawn out before it calls for refilling. One possibility is an underground leak. I don’t suspect this because I put the piping in myself and it was under pressure and not leaking when I buried it. Sure, it could have a leak now, but… Second possibility is that the pressure tank is forcing water thru the check valve and back into the well. I can’t think of other reasons. There are no leaks in the house piping. It’s all accessible under the house and I’ve checked it all carefully… all dry. Any ideas?
And, how many gallons should the tank provide (from full) before cycling?
Replies
"Once in a while, it will cycle first thing in the morning shortly after the first flush or run of the tap."
Sounds like perfectly normal operation to me. "Once in a while" you will almost use enough water to run the pump the night before. So any water usage in the morning triggers the pump.
If you have a leak or a backflow, the pump would be triggered without any water usage at all.
To check easily, on a day no one will be home, the last person to leave runs water until the pump triggers. Turn the water off and let it pump til the pressure switch turns it off. Note the reading on the pressure gauge. Then cut the power to the pump.
When you come home, check the pressure gauge. If there's a leak or backflow, the pressure will be down.
Rich Beckman
Another day, another tool.
Helluva good idea. Sorry about your belt sander cord.
another possibility to check on is a waterloggeed tank ( minimal air volume)
Tank is about 9 months old... hope they last longer than that. How does one check it out?
The fact that the last flush of the night before left the tank just above the starting point is a good guess.
But you might also have a leaking stool.
First thing we need to know to prevent you from wasting time and effort in determining if there's a problem is.....
Is this a single compartment pressure tank or a bladder type tank?
(Diaphragm tank is possible, but are pretty rare these days)
If you don't know, this can likely be determined by where the water delivery line from the pump enters the pressure tank. On the side, top or on the bottom of the tank?
Bottom would indicate bladder tank, particularly if you can see a large plate under there that's bolted around its perimeter.
Knowledge is power, but only if applied in a timely fashion.
The piping enters the bottom of the tank. The tank is designed to stand vertically but is installed horizontally due to its location. I was told this was fine and have seen others installed the same way. I haven't looked at it in a while but I do not remember a bolted-on plate anywhere... I can go take a look if need be.
I am not an expert but I have always had wells my entire life. I agree with a previous post about the pressure being almost down to the point just above were the pump would kick on from previous days use. then first thing in the morning you flush a toilet or turn a faucet on and the pressure drops the rest of the way.
Well….because I can't see your tank here, I'm gonna assume it's a single compartment type with no separation of the air and water….judging from your description.
And I'm also gonna suspect that because the tank is on it's side down there, it has no air/water volume control and so the air in the tank is subject to absorption by the water. As time passes by and more absorption takes place, the draw-down capacity of the tank will lessen and eventually things will arrive closer and closer to the point where we would call the situation……a water-logged tank. The result of that is very little draw-down of water before the pressure switch kicks the pump back in. When the problem gets severe enough, the pump will kick in and out with the slightest bit of water draw from the tank. Not good at all. Very hard on the pump.
But to determine if your system has such a problem, how bad the problem might be and/or if it's running at optimum draw-down, we need to get some hard info. First thing you'd need to do is to cause the pump to trip and fill your tank. Just in case you need to know later and don't already, note the reading on the pressure gauge when the pump finishes filling the tank. Then you need to position yourself and/or a helper so that you can measure how much water you get to remove before you hear the pressure switch click indicating the draw-down is over. And so, before drawing off the water, turn the current off to the pump. Use a container of known capacity like a 4.5 gallon or 5 gallon bucket.
When you hear the pressure switch click, immediately stop drawing water and tally how many gallons you've drawn out. Now check the reading on the pressure gauge again. For the sake of discussion, let's assume you have a 30/50 switch and that's what you observe as the readings of high and low.
Now we hope you have a boiler valve or the like installed at the low point of the plumbing near the tank so that you can completely empty the tank of all water. If there isn't one there, see if there's a union in the line at a similar low point that you can unthread to accomplish the same.
Now we hope there's a Schrader valve (tire-air valve) in the pressure tank so you can take readings and add any needed air to the tank. What we're wanting to do here is optimizing the draw-down by treating your single compartment tank as if it were actually a bladder tank. (And if I'm wrong and it is actually a bladder tank, you should check this out and adjust it anyway.)
First take a reading and see how much, if any pressure is left in the tank once all the water has been allowed out. Probably don't need to suggest that a little compressor will be alot easier than a hand-pump here, especially with a tank that size.
If you have a 30/50 switch, you want to have 28 psi of pre-charged air. No matter what your switch range is, you'll want the pre-charge to be 2 psi less than the bottom setting. If it's 20/40, set the pre-charge to 18 psi.
Once you have the pre-charge done, turn the current back on and let the tank refill. Repeat above draw-down test procedure. Any difference in the draw-down gallons?
Here's a few calculations that illustrate how important the proper pre-charge can be to your well pump.
If you have a switch that is set for 30/50, your optimized draw-down would be 29.5% of the total capacity of the pressure tank………119 gallons x .29.5 = 35.1 gallons of draw-down.
If you have a 30/50 switch running on a non-pre-charged tank, the draw-down would only be 10% of the tank capacity. 119 gallons x .10 = 11.9 gallons of draw-down.
That's a big difference from the same tank and is one of the reasons why pre-charged bladder tanks are used wherever possible and appropriate these days, but what most folks don't realize is that there isn't any reason why you can't pre-charge a single compartment tank.
But the problem you'll continue to have if your tank is single compartment and has no air/volume control is that this air absorption will continue to take place as time passes. And so that will necessitate periodic recharging if/when you notice more frequent cycling of the pump indicating draw-down is substantially reduced because of gradual water-logging.
None of what I've described above is going to tell you if you have some problem that is actually leaking air or water from your system, but it will tell you what the optimum draw-down is and that should be valuable in determining if something has gone awry that needs your attention.
You can check my math here if you like. I'll admit I rushed it.
http://babyurl.com/4FSSIc
(If you do have a 30/50 switch and you get anywhere near that optimum 35 gallons of draw-down, there's no reason to got hru the rest of the pre-charge procedure really. If your draw-down is substantially less than that, you probably should for the sake of pump.)
Knowledge is power, but only if applied in a timely fashion.
Edited 8/29/2004 5:59 pm ET by GOLDHILLER
Edited 8/29/2004 6:42 pm ET by GOLDHILLER
Thanks for the very detailed reply. It's quite clear and I will go ahead and check out how the tank is functioning. It will take me a couple of days to get it done but I'll get back with the results.
Cute dog on your profile. My dog partied like that when he was younger.
OK... I done checked it out:
The label says it's a 60/40 setup and that's about what it does when cycled, although it gets to maybe 59 and 41. It says drawdown should be 31.5 gallons. It also says pre-charge is 38.
I used a 32 gallon Roughneck trash can that's 28" tall for the test, and it filled to 24". Roughly accounting for the taper I figure I got 25 or 26 gallons out of it before the switch clicked.
There is indeed a Schrader valve on the 'top' end of the tank. It's under a seal that says 'Do Not Break' but I broke it anyway. I tried to test it with the tire gauge from my truck and it maxed the gauge out at 55 PSI, with the tank full. I did not drain the tank to check it empty but there are valves to isolate the tank and I can do that if I need to.
There does not appear to be any bolt-on access panel anywhere. Do they weld the tanks with the bladders in place?
Whaddya think? Is this within range for a tank that's been in service one year? My neighbor is the local well driller and he supplied the tank, and said it's fine on it's side. I don't mind tuning it up once in a while but it'll suck if it dies prematurely, because getting a new one in there and connected will be a day's work.
Edited 9/6/2004 3:54 pm ET by davidmeiland
The bladder tank that I have has a large (4 -6") flang on the bottom where and held by a number of screws. In the center is the inlet port. Unless you was looking for it you would never know that it was there.
I pump out of a lake just for irragation and it get drained each year.
I have over 100psi on the city water. This year I redid the systen and moved the tank and got a new pump. I set it up so that I can "precharge" it with city water. Save some time priming the system. Anyway I put a little water in it to see if the new connection held. Then turn the city water back on and got distracted. Several minutes later the pressure guage on the irragtion system was peg at 100 psi and water was spraying out around the flange. That is the only reason that I know that the flange was there.
Blead of the pressure an started the pump and it has not leaked at 40-60 psi since.
Anyway with that draw down you are fine.
Also if you want to check the pressure then turn the pump off and drain the water. If you have pressure then the bladder is OK.
The fact that it says PRECHARGED indicates that it has a bladder.
With the tank on it's side can I expect to drain 100% of the water?
Dave,
I agree with Bill on this one. If you're optimum drawdown is 31.5 and you're getting approx. 26, then I wouldn't bother messing with it at this time. Seems your initial concern about hearing it trip first thing in the morning once in a while is just coincidental to the tank presssure cycle.
And/but.....yes.......the only way to truly determine what the precharge is....is with the tank devoid of water.
And no.....I haven't ever personally seen a bladder tank that had a welded, rather than bolted.....plate. That's how they get the bladder in there and how you'd be able to replace that bladder should it fail.
I can see how you'd have problems draining the tank competely of water with it on it's side.
But it *might* be that this isn't a bladder tank since you don't see a round bolted plate down there. Don't know what to say for sure on that account. But .............if the drawdown drops significantly in the future sometime, you could always turn the pump off, deplete the tank of as much water as it'll give off and then toss a SWAG of air into it and see what your drawdown is then. If it isn't a bladder tank and you get too much air into it, it'll throw air out the faucet before the pressure valve tells it to start the pump.
How's about digging a little in that crawl space so you can stand the thing up? You know.... the way God intended for it to be anyway. LOL
Anyway, I think you've got a handle on how this all works and so you'll know if things start acting up in the future. For now, it sounds okay with that 26 draw-down.
Oh yeah. Shoulda said that since you now know what the draw-down is......if you still suspect that there may be another problem (a leak) resulting in more frequent cycling.........then you could test for that. Make sure tank is fully charged when you know that no one or nothing will draw water while you're gone for the day (don't forget stuff like a humidifier on a forced air furnace). Turn the power to the pump off as soon as tank is fully charged and then check the draw-down gallonage as soon as you return home.
As a matter of fact, you shold do that right away..like in the next day or so. Reason is that if this isn't a baldder tank or the bladder is torn (in which case it will act like a single compartment tank) the water will slowly absorb the air and that'll naturally reduce the draw-down over time. Could give the appearance of a leak when there isn't one. Checking it for the potential leak now..... would give you peace of mind....for the time being anyway.
Knowledge is power, but only if applied in a timely fashion.
Edited 9/6/2004 10:59 pm ET by GOLDHILLER
Edited 9/6/2004 11:10 pm ET by GOLDHILLER