I've been seen some youtube videos but I would like to make sure I am doing it correctly as it seems that my pressure tank does not have any air.

This is the way I did it yesterday:

turned off the breaker
drained the water from the closest restroom to the pressure tank by turning on the sink faucet until there was no water left.
Checked the pressure of the tank and there is no pressure at all

Can someone please advice. Thanks.

Depending on the tank, but we always open a faucet with pump off then added air to the pressure needed. Is you pump cycling too much, they get water logged. Air in the tank allows for draw down before pump turns on.

 

Attached are some pictures of the tank and how the pressure reads 0.
The model number of the pressure tank is LPT-20H 100

 

When the tank is empty you should pump it up to 2 psi less than the pump cutin pressure. If it won't hold the pressure then the bladder has broken.

 

Today, I tried to put some air following the above procedures and when I was in putting some air, I heard water gurgling inside the tank so I stopped.

Is there supposed to be some water left in the tank after it has been drained from the closest faucet or sink?

Also noticed that when water is running, the pressure switch cycles on and off about every 20 seconds.

Attached are some pictures of the tank and how the pressure reads 0 after draining the water from the closest faucet or sink.

The model number of the pressure tank is LPT-20H 100

 

There will likely be some water in the tank unless the faucet used to drain it is lower than the tank. As you pump air in the water will be pushed out. If the air starts coming out the faucet the bladder is bad.

 

Thanks for your response and clarification Joed. Now, what could have happened to the air that was in there? A leak? The tank should have been precharged with at least, I was reading 30psi, maybe someone can confirm this.

Also, the little air that I have put in, it seems it does not make any difference as I keep checking and it does not raise at all. Maybe leave the gauge air in the tank continuously for at least what, 5 min and see what it does?

I just don't want that tank to blow up on me you know.

 

If the bladder breaks (wore out? biodegraded?) during normal operation of the system then the air in the pressure tank willl be gradually absorbed by the water. The pressure will still rise and fall between the same pump shut off and pump turn on pressures you were using e.g. 60/40 but more water will rise into the pressure tank. With more water remaining in the pressure tank when the 0pump starts and less of an air cushion, the pump cycles will gradually become shorter and shorter which is undesirable.

When you try to drain the pressure tank and the pressure drops to near zero, any water stilll in the pressure tank will not come out and the open faucet stops flowing. You need to add more air to the pressure tank via the top valve (Schrader valve) to get the rest of the water out. Then with the faucet still open you add still more air to re-preset the tank to pump turn on pressure minus 2 PSI. Finally, close the faucet and turn the pump back on.

 

Thanks for your response AllanJ. The pressure tank is only about 3 years old. When I checked the schrader valve, no water came out it.

When I've tried to put air in the tank and leave the air house for a few seconds into the tank's schrader valve, it seems like no air is going into it. When I check it with my pressure gauge, nothing changes.

Do you think I should leave my air hose at least maybe a minute or two and see what it does?

 

If there is a pin hole size leak , that over time allowed the bladder to fill with water , that tank is ready for the tank grave . It would take about as long to force the water out as it took to fill with un-desired water through the pin hole .

If someone selling mentions replacing the bladder politely walk away . It ain't going to happen . I don't recommend even attempting to remove the bladder .

If the bladder is full of water the tank will be heavy , otherwise drained it may weigh 15 lbs. for a small tank . Full of water , the on /off cycle will be seconds rather than minutes .

 

Pumping air into the pressure tank must be started with a faucet open and the pump off. If you have "zero" pressure to begin with it will take some time befroe the gauge starts to move up. But watch it. Once the gauge moves up it is easy to forget and come back to find out there is overpressure.

"Hold the hose, don't leave it."

 

Thanks AllanJ. With over-pressure, there is a chance for the tank to burst right if one keeps pumping air into it right? Now, do you think there is a leak in the bladder and that's why it does not have any air?

 

The fill valve could have leaked the air out or there could be hole in the bladder. Leave a faucet open and try pump up the tank. If it won't pump up and air starts coming out the faucet your bladder is bad.

 

Thanks joed. Would there be a risk to maybe without any unknown reason pump too much air into the tank to the point that it could burst?

 

Monitor the pressure like you do when you inflate a tire. Plus I doubt you have a pump that will get above 100psi and the tank will take that no problem.

 

Well, a friend of mine who is an expert just stopped by and told that the bladder has a leak just for the fact that the pressure switch keeps cycling every 20 seconds with the water on so that means that the tank is not holding pressure.

I guess that makes sense as I assume that if the bladder in tank is okay, there is no reason to put some air into the tank.

He did mention to me that because the pressure tank is currently feeding four mobile homes, I should have an 80 gallon tank. There used to be two tanks in the system but one went bad and it has not been replaced since then. So right now it is only running with one tank.

Currently, I cannot do the 80 gallon as I have to buy a little building to put it on. The current one is under one of the mobile homes. In the meantime, I would like to buy another one and put it in the same location where it used to be. Being that the current one is a 20 gallon, should I buy another 20 gallon? Does it matter if a buy one with a bigger capacity and have mismatch in the system?

 

Bigger will not be a problem. It will just mean the pump runs less often but for a longer time when it does run.

 

QUOTE: \
and told that the bladder has a leak just for the fact that the pressure switch keeps cycling every 20 seconds with the water on so that means that the tank is not holding pressure.

QUOTE:
Also noticed that when water is running, the pressure switch cycles on and off about every 20 seconds.
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When buying a new tank , it's more convenient if the new and old tank water connections are the same elevation from the tank base .

 

Attached is the inlet where the pressure gauge is attached...I guess this is preventing it from functioning properly correct? How can I avoid this? Maybe using a copper inlet with a copper nipple?

 

FYI the 1/4" nipple that connects the pressure switch can corrode just like this one to the gauge , plus some of that rust can enter the pressure switch to make it faulty . I cleaned my pressure switch with a vacuum and old tooth brush . IIR from 20 years ago there is a diaphragm in the switch immediately after the connection threads .

 

Because the pump makes very short on off cycles does not in itself prove that the pressure tank bladder is broken.

You have to go through the motions of pre-pressurizing (re-pre-pressurizing) the pressure tank.

The pressure tank could have gradually lost its air cushion out the air valve due to a leaky or imperfectly closed latter

"" I guess this is preventing it ""

If the inlet is clogged (can't see from this vantage point) then the gauge attached to it won't register correctly. A copper replacement will last a long time but a steel one will work at least for a little while.

"" currently feeding four mobile homes ""

Additional not so large pressure tanks will work just as well as replacing the single existing tank with a larger one. (The existing tank can stay in place connected.) Each pressure tank should be pre-pressurized as if it were the one and only, with the pump switched off and the pipes depressurized. The additional pressure tanks can go anywhere but preferably before any of the faucets or garden hose bibbs in any of the homes and definitely before any softeners, water heaters or other in-home accessories..

 

When I was younger, 60 years ago, we had tanks with no bladders. All I remember was when pump cycled to much dad would drag a air hose to the pump and open faucet and put air in until start in until started coming out. Every thing worked fine until got water logged again.

 

Just moved from a property with 2 wells and 1 of each pressure tank style . I just drained the non-bladder tank for considering contamination the water system with compressed air . We can easily see where the water level was 99% of the time for 45 years . If tanks weren't so expensive i would have replaced the bladder tank with non bladder tank .

 

So a pressure tank can loose air through out maybe a couple of years? So the fact that a pressure tank does not have any air when depressurized or with the water drained out does not mean that there is a hole in the bladder?

So as long as the water is drained from the closest faucet to the pressure tank, one can check the pressure in the tank even though there is still water in the tank right? Someone previously mentioned, whenever one drains the water of a pipe system to check air in the pressure tank, that does not mean that all the water of the pressure tank will come out.

I replaced the pressure tank and noticed that the old tank still had water in it.

 

RE: Non bladder tanks. "" drag a air hose to the pump and open faucet and put air in until air started coming out {the faucet} ""

Refinement: Then close the faucet and pump more air into the tank and watch the gauge until you get to pump start pressure minus two. Finally turn the well pump back on. Now it will take much longer before the tank waterlogs again. If this were done for 45 years the stain on the outside of the pressure tank showing the average water level would have been much further down.

Air can be lost from the pressure tank due to a less than perfect air valve (Schrader valve) on top. So waterlogging is not proof positive the bladder has burst.

If the bladder has burst then behavior of the pressure tank can be unpredictable. A flap of torn bladder could block the pipe connection down below and keep the tank from emptying out normally or with a faucet open. So long as the pipe connection is not blocked and the bladder tear not temporarily sealed shut against the tank side, the tank with the burst bladder will behave like a non bladder tank.

 

Hi guys, sorry went off track on this one and totally forgot that I ended up replacing the pressure tank and that solved the issue. Now, I had another question: How big a pressure tank should be to feed four mobile homes?

 

The purpose of a well pressure tank is to prevent frequent stops and starts of the pump. With 4 dwelling, go as big as you can get.

 

One pump and four homes -- I would go with a minimum of two 30 gallon bladder tanks in the pump house before the branching to the four homes. One check valve just before the pressure tanks.

The most stress will occur if several faucets are open in the various homes. But the pump on time won't be that short because the pump is feeding all those faucets and it will therefore take longer for enough surplus water to build up the level in the tanks and reach the pump cutoff point.

(To recap: More water having entered the pressure tank equals smaller air cushion in the tank equals higher air pressure in the cushion equals matching and higher water pressure in the plumbing equals higher pressure sensed by switch that controls the pump.)