I have a standard well set up with a bladder pressure tank. Cut on pressure is 30 psi and cut off is 50 psi. Precharge is 28 psi.

In the 9 years I have had this set up I have had the bladders in various pressure tanks rupture - I have been through about 6 of them. I check and maintain the system scrupulously and have had professionals check it to ensure I am not doing anything wrong. I cut open one of my old pressure tanks that had a ruptured bladder and the bladder indeed had a small tear in it about an inch across. The inside of the tank was very clean and had no debris.

I'd appreciate any advice as to what could be causing the constant rupturing of the bladders in my tanks. Thanks.

Is the tank properly sized to the pump?
With any flowing water shut off as soon as the pump starts, the pump should run at least a minute before the pressure switch shuts the pump off.
If the pump runs less than a minute, the tank is too small which causes excessive wear on the bladder & the pump.

The only thing I know of that can cause a tank's bladder to fail is chlorine. Is your water chlorinated?

Thanks for your response. It is a 20 gallon tank (about 6 gallons drawdown) and used mainly for irrigation. The system is used for about 4 hours of continuous operation about every second day in the summer.


Thanks for your response. It is a 20 gallon tank (about 6 gallons drawdown) and used mainly for irrigation. The system is used for about 4 hours of continuous operation about every second day in the summer.

Oh, and the water is not chlorinated. It is well (bore) water that is quite high in iron.


Is the tank properly sized to the pump?
With any flowing water shut off as soon as the pump starts, the pump should run at least a minute before the pressure switch shuts the pump off.
If the pump runs less than a minute, the tank is too small which causes excessive wear on the bladder & the pump.

Sorry for the multpile posts. I just timed the tank fill - it only takes about 40 seconds. So maybe that is my problem (the pressure tank was matched for me by a 'professional' and no one has commented upon it in 9 years)!

20 gallons is small. 4 hours of continuous operation means a lot of cycles of fill/empty. You might want to consider a galvanized tank which does not have a bladder. The only down side is having to recharge the air in the tank every few months. If the tank is easy to get to, then that is not much of a job.

You could also think about using a larger bladder tank. The issue of "sizing" a pressure tank has never struck me as rocket science. A larger tank has the advantage of fewer starts/stops for your pump, which is a good thing.

If your water has a lot of iron in it the water is probably also acidic. I see way more bladder failures with acidic, high iron water than with neutral, low iron water. Maybe the iron/acid makes the bladder brittle. Would be a good question for a tank manufacturer.

20 gallons is small. 4 hours of continuous operation means a lot of cycles of fill/empty. You might want to consider a galvanized tank which does not have a bladder. The only down side is having to recharge the air in the tank every few months. If the tank is easy to get to, then that is not much of a job.

You could also think about using a larger bladder tank. The issue of "sizing" a pressure tank has never struck me as rocket science. A larger tank has the advantage of fewer starts/stops for your pump, which is a good thing.

Thanks - that does make sense. I will definitely get a bigger tank next time around. I have very easy access to the tank and don't mind recharging as necessary, so it sounds like no bladder would be the way to go.


If your water has a lot of iron in it the water is probably also acidic. I see way more bladder failures with acidic, high iron water than with neutral, low iron water. Maybe the iron/acid makes the bladder brittle. Would be a good question for a tank manufacturer.

Thanks for this. I will check the analysis of the water and, if acidic, will be interested to see what the tank manufacturer has to say.

If the water is acidic, particularly if below pH 6.0, I think I'd steer clear of a galvanized tank. Don't know if stainless is an option or not but if available it might be worth looking into. BTW, "glass lined" is a joke.

According to my water analysis it has a pH of 7.3 - so should be no issues there.

What is the issue with 'glass lined' tanks?

PH sounds nearly ideal.
The supposed 'glass lined' tanks are simply coated with a micro thin coating which is very brittle. Most tanks are made with the fittings spin welded to the tank. I think this is done after the coating has been applied but I'm not sure on that particular point. If that is indeed the case, the area around the fitting is not protected.
I'm at a loss to explain why you are getting so many bladder failures unless it is a reaction to the iron. Six tanks in nine years is WAY too many.
I'll check with the guys at my local pump supply house to see if they have any ideas. They deal with tanks & pumps every day.

Do you know they actual iron content of the water?

Thanks - the iron content is 0.88mg/L.

I'm wondering if the problem is, as originally suggested, the tank is too small and is working way too hard and just wearing out - i.e. normal wear and tear accelerated through overuse.

However any other ideas would be much appreciated.

Have you contacted the tank manufactures and what were you told> Back to you, Tom

I have - unfortunately they have been unable to offer an explanation over and above 'bad luck', and have just replaced the tank on each occasion. But I think there are too many failures for it to be just 'bad luck'.

Further to this, one unusual thing on my well set up (that the manufacturer does not think is relevant to my pressure tank issue) is that very early on the check valve on the pump failed and so a new check valve was installed at the top of the well. This means that when the pump switched off the water below the check valve (ie in the pipe in the well) empties out, and when the pump switches back on it has to 'refill' the pipe in the well. While being inefficient (due to having to refill the column of water every time) does anyone think it relevant to the pressure tank problem? Thanks.

Unless there is a leak between the check & the bottom of the well, the check should hold the pipe full of water.

Checked with my buddy at the pump supply house today & he had some questions to which I wasn't 100% sure of the answer so I'll ask:
1. Is this a jet or submersible pump?
2. Is the well in question just used for irrigation or does it also supply your domestic water?
3. If just irrigation, do you also have a problem with the domestic well tank?
4. If two wells & no problem with the domestic, what differences are there in the two systems?

Sorry to be so full of questions & so few answers so far but maybe we'll come upon an Ah-Ha moment.

I'm presuming the water is escaping at the bottom of the well through the submersible pump (because the check at the pump as failed).

To answer your questions:

1. submersible pump
2. used just for irrigation
3. I don't use a well for domestic water (I am connected to town water which I use for domestic water - I have a well for irrigation because town water costs are very high). Ie I have only one well that is used only for irrigation

Thanks!

I don't think the CV is your problem. If it was leaking, you would notice pressure dropping at the tank when water is not being used. That would be due to water simply leaking back into the well. It is better to have a CV above the pump, but as you have discovered, having one at the wellhead will work as well.

If you only use the well for irrigation, you might want to consider doing away with the pressure tank. Just turn the pump on when you want water.

Thanks. Some of the irrigation stations have a very low draw, e.g. lines of drip emmitters - would this be a problem for the pump without a pressure tank? And, on a related note, do you have a view on cycle stop valves?

Don't know a lot about cycle stop valves. This site sells them. Cycle Stop Valves, Inc. (http://www.cyclestopvalves.com/simple/home.php). This site explains them: http://wellwaterproducts.com/categories/Cycle-Stop-Valve/

Just using drip irrigation would be a problem. Probably doesn't use much in the way of volume, so not having a tank would be tough.

sg0148,
I have not forgotten you. Just haven't had 5 minutes to stop by & talk some more with the guys at the pump & well supply house. It's been crazy busy at work & I'm getting way too much windshield time.

Don't know a lot about cycle stop valves. This site sells them. Cycle Stop Valves, Inc. (http://www.cyclestopvalves.com/simple/home.php). This site explains them: Cycle Stop Constant Pressure Control Valves (http://wellwaterproducts.com/categories/Cycle-Stop-Valve/)

Just using drip irrigation would be a problem. Probably doesn't use much in the way of volume, so not having a tank would be tough.

Thanks very much for this info.

sg0148,
I have not forgotten you. Just haven't had 5 minutes to stop by & talk some more with the guys at the pump & well supply house. It's been crazy busy at work & I'm getting way too much windshield time.

No problems - thank you.

At long last I finally got to talk to the guy I needed to & was told if you have any grit at all in the water it's going to be extremely tough on bladder tanks. Also if the iron in the water is plating out onto the interior of the tank, it could cause you problems but not as severe as the grit. His suggestion was to install a "sand sock" on the pump or at the very least what I think he called a Campbell cyclonic filter with a 200 mesh screen.

Thanks very much Grady - I'll give that a go.

As the water definitely has grit in it.