I've noticed a change in water pressure in my well water. I have checked everything (pressure valve, bladder tank, filters) and everything is good. I watched the pressure on my gauge go up to about 58 lbs and then drop down to near 50lbs and stops (I closed the line going to the house so I can see if I am losing pressure back down my pump). My switch is a 30-50 lb switch. Today I am getting a lot of air in the line. I can't figure it out. From my testing and from reading online I don't have a problem anywhere.

Suggestions?

My pump is 210 feet in the ground. I have a 30/50 switch. Yes, pressure builds to about 58 lbs and then drops to about 50 lbs pressure when no water is being used and valve is shut of after the bladder tank so that no water is going to the house. So you got the picture correct.

This house was built in 2004, so it has had this bladder tank in it. The pressure switch is what I was referring to, which is at the base of the bladder tank. There are no leaks around any of the lines I have visual contact with. The checkvalve is on the pump itself, correct?

The problem now is to figure out where my check valve is located. Where the line comes into the basement it is all PVC and it is PVC until it gets to the bladder tank. There are no check valves located in my basement. Would the check valve be located in the well itself or on the pump?

Sunday I drained the pressure (bladder) tank. I checked the air pressure and there was none. I pumped in 28lbs of pressure. Monday morning I had a lot of air in my water line to my shower. So I am concluding my 7 year pressure tank's bladder is leaking. It is an 82 gallon (that is what it says on the tank), but only stands about 4 feet high. From what I read online, I don't need a tank that big. There are only two of us living in this 1800 sqft house.

Anyway, confirmation please on my conclusion.

Thanks

Is your pump in the well or above ground?

You have a 30/50 switch, but pressure is going up to 58, then drops back to 50 even though no water is being used. Is that the picture?

When pressure drops even though no water is being used, that usually points to a leaking checkvalve. That might also explain the air in the lines. As the water drops in the wellpipe, even the slightest leak in a line would allow a little air to enter. When the pump cuts back on, whatever small amount of air is present get pumped up the line.

Using a hammer or the end of a screwdriver, gently tap the pressure tank, starting at the bottom and working up. You can generally tell when you are hitting empty tank vs. tank with water behind it. Does it seem empty, or does it seem about half full?

Have you always used a bladder tank, or did this system ever have an old galvanized tank on it?

You mentioned having checked a "pressure valve". Did you mean the checkvalve or the pressure switch? If so, how did you check it? If the pressure switch, did you happen to check the little pipe that leads to the switch?

The pump is not terribly old, so it would be unlikely the CV on the pump is leaking. It is hard to say if there are others. The general consensus is that the CV on the pump is the only one you need, but not everyone does it that way. I would check the tank as I described. It should be about half full. If it is largely empty, then you have to start figuring out where the air is coming from.

There is definitely one on the pump. As to others, it's hard to say. There is often one installed near the tank, but in your case that appears not to be the case.

At any rate, check your tank as described above. If you are getting some air pumped, then the tank should be largely full of air.

The tank might be bad. However, even if it is, I've never heard of a pressure tank causing air in the lines. Even if the tank is bad, you can drain it as you did which will allow air into the tank. That allows the tank to work properly until all of that air cushion dissolves into the water (several weeks) and the tank becomes waterlogged. In other words, I just don't think the tank is the source of the air in your lines. But if you want to replace it, you are correct in thinking that you could do with a smaller one. A tank the size of yours will cost at least five to six hundred dollars or more. A forty gallon tank will be half that cost and work fine.

Before you replace anything, I'd like to see you drain the tank again through a low level faucet with the system off. Get it empty as much as you can. Don't pump any air in it, simply turn the power back on. The tank empty will contain enough air to make it work. See if you still have air in your lines then. If you do, then I would think the tank would not be the source.

http://www.aquascience.net/amtrol-pr...dex.cfm?id=508

Note,
txasylum generated 6 threads under this one heading covering several days. I merged all the threads and answers into one thread. In the future, if you have anything to add to your post use the "edit button instead of starting a new thread. Thanks, Tom

Tom,
I hate to do this when you said to use the "edit button instead of starting a new thread", but I've searched and searched and cannot find the edit botton. Please tell me where it is.

I will drain the tank again tonight from the faucet at the base of my tank/pressure switch. Just past that point I can turn off the water to the upper levels of the house. As for air, last week when I had air in the lines it was very noticeable and only lasted a short period. After all the air was out, then the pressure was weak, especially if two or more faucets/toilets/shower was on (which previously I did not have weak pressure). Last night after I put air in the tank (because there was none), this morning is when there was air in the lines. So I'm assuming that air won't last long in the lines again. I really doubt it is the check value because I am not losing pressure back down the well line. The pressure holds steady after the pump shuts off (with the exception it drops a couple of pounds right when it shuts off then holds steady at 50lbs).

As for the size of the tank, after looking on line at replacement tanks, I may have read my label wrong. It is possible I have a 35 gallon precharged with an output equivalent to 82 gallons. (My tank shows 82 gallons, but the size of it looks more comparable to a 35 gallon precharged. I need to get more data on my tank and look it up to be sure.

You are no doubt correct about the tank size. You are also correct that your cv is probably good if pressure only drops a pound or two after the pump cuts off. You originally stated it dropped from 58 to 50, which would be unusual. It is also normal to have a little air in the lines after you work on the system which typically clears out in a matter of minutes. I was under the impression that the air problem was fairly constant.

What you are describing is really not a pressure problem so much as a volume problem. In other words, when only one faucet is on, you have good pressure and, as you stated, the gauge reads between 30 and 50. However, a second faucet being turned on results in a noticeable drop in pressure at each faucet. That usually indicates an obstruction somewhere which prevents enough water from being able to get through to supply two faucets. Do you have a water softener on this system? Have you checked your shutoff valve to be sure it did not collect some trash and is partially blocked? Also bypass your filter to be sure it is not the problem.

The edit button will be at the bottom of any new post you make on this thread.