Bladder tank?

[Geo-TH,In]

How closely should the bladder tank pressure be to the water pressure? If the pump turns off at 40 psi, should the air pressure be 40, a few pounds less or a few pounds more?

Let's say the pump pressure drops to 20 psi. Again what should the air pressure be?

Thanks,
George

 

[PJH]

George, my paperwork for my water system is out in the shop, so I googled "bladder tank pressure" and got the following answer. From memory, it seems to agree with the papers that came with my bladder tank.


"The ideal air bladder pressure is 2 PSI below the cut-in pressure of the water system. In other words, if the system is set for a cut-in pressure of 30 PSI, the air bladder pressure should be 28 PSI."

Paul

 

[MarkB_MI]

The important thing is the tank precharge pressure must be LESS than the the cut-in pressure of the pump switch. If the precharge pressure is more than the cut-in pressure, you'll run out of water before the pump kicks in.

As long as you don't lose water pressure before your pump kicks in, it's probably OK. The optimal setting is to have the pump setting 2 psi higher than the precharge pressure. If it's higher than that, you're wasting tank capacity but it's no big deal. To check the precharge pressure, you need to completely drain the tank of water. I think most tanks are precharged to 38 psi, assuming typical pump switch settings of 40/60 psi.

 

[Geo-TH,In]

Paul, I did google bladder tanks, there are 3 different tanks, 20/40, 30/50, 40/60, each is precharged to 2# less than the cut in.

Without draining the tank, I just what to know what will be the actual working pressures inside the tank? Will they follow the water pressue?

I have a 20/40 tank on one well and a 30/50 on another well different location.
George

 

[Paul Janke]

With the system turned on, the air pressure is exactly the same as the water pressure.

 

[Geo-TH,In]

Paul,
That's what I was thinking. Is there any way it could be more or less?
thanks.
George

 

[showcrop]

(quoted from post at 05:33:09 12/31/13) Paul, I did google bladder tanks, there are 3 different tanks, 20/40, 30/50, 40/60, each is precharged to 2# less than the cut in.

Without draining the tank, I just what to know what will be the actual working pressures inside the tank? Will they follow the water pressue?

I have a 20/40 tank on one well and a 30/50 on another well different location.
George

George, you can adjust pretty much any tank to match up with the pressure that you are running at the houses. That is what the schrader valve on top is for. Just bleed off or add air.

 

[Paul Janke]

It could be more only by having the air pressure above the pump shut-off pressure. And less only by having no air pressure at all in the bladder. In either of those cases, it would be the same as not having a pressure tank and the pump would short cycle to the extreme.

 

[MarkB_MI]

The only time the air pressure is more than the water pressure is when the tank is empty. The only way the water pressure can be greater than air pressure is if you bleed all the air out so the bladder is collapsed and the tank is full of water. Remember, for any force there is an equal an opposite reaction. The bladder moves up or down until the pressures on either side of it are equal.

HOWEVER, you're probably using two different gauges to measure the air charge pressure and water pressure. It is very unlikely two gauges will read the same, particularly if one is a tire pressure gauge.

 

[Geo-TH,In]

I think I got the bladder tank in sink with pressure switch. Adjusted swith to 20/40 and both tanks, have 2 tanks in parallel, where the air pressure is same as water pressure.

Something weird is happening to my flowmaster toliet shutoff valve.

If I put the small hose from flowmaster where it belongs, the toilet runs all the time, as if the flapper valve is leaking. If I remove the small hose and put in the tank, toilet doesn't run. This is been bugging me for a long time on 3 different toilets. There has to be an issue with flowmaster water shutoff. It definately isn't the flapper valve.

Many thanks.

George

 

[showcrop]

(quoted from post at 10:52:40 12/31/13) I think I got the bladder tank in sink with pressure switch. Adjusted swith to 20/40 and both tanks, have 2 tanks in parallel, where the air pressure is same as water pressure.

Something weird is happening to my flowmaster toliet shutoff valve.

Did you adjust the float down a little?

If I put the small hose from flowmaster where it belongs, the toilet runs all the time, as if the flapper valve is leaking. If I remove the small hose and put in the tank, toilet doesn't run. This is been bugging me for a long time on 3 different toilets. There has to be an issue with flowmaster water shutoff. It definately isn't the flapper valve.

Many thanks.

George

 

[El Toro]

When I had well water in my other house the pump came on about the time I opened the faucet. I installed several of those air volume controls that didn't help. My neighbor sold me one and it wasn't worth the time to install it. He did plumbing on the side. We bought a lot of plumbing supplies from a local plumbing warehouse for the government. I stopped there and asked the manager about my tank getting watered logged. He said I have the fix and showed me the bladder tank. I bought the tank and installed it.
That fixed my water logging problem. When I told my parents about the new tank my mom said to get them one as their tank was always water logged. It was used until all that well water was found to contain benzene in all the houses in that area. They ended up with county water and sewage. This was in 1963. My nephew inherited the home in 2008. Hal

 

[Sean Feeney]

Take a look at the first couple of minutes
Video

 

[guido]

Hello George march,

My tank label states that is pre charged at the factory to 38 psi pressure. It had 41 psi. when it was put into service, probably due to the heat of that day,

Guido.

 

[Two Dogs]

Mark, you make it sound as if air is in the bladder instead of water. TDF

 

[Geo-TH,In]

Sean,

I do use the fluidmaster valves. I buy many of them for about $5 when Menards has a sale. I use them in all my rentals. I know how to take them apart to clean them. Sometimes there may be sand or something that won't let them shut off 100%. Or something in the tube that causes a restricted flow. However the weird thing it will leak with the fill tube where it should be and not leak when the fill tube is in the tank.

All I can think of is the water pressure varies, one place is from 20-40 another is 30-50, it may leak a little at the higher pressure. All I know is you can see it leaking, leaving rust stains on the toilet. I've tried many things, it's madding.

George

 

[MarkB_MI]

George, just to be clear, if you have two tanks, the only way to balance their precharge is to completely drain both tanks. Otherwise, they'll both have the same pressure as the current water pressure, even if one is overcharged and the other is undercharged.

 

[Geo-TH,In]

After setting the pressure switch to 20-40, letting some air out of both tanks, the air pressures in both tanks track the water pressure. All is good.

 

[Jeff B.]

On one of the toilet valves I had, I had to adjust the depth of the little hose up or down until it was just right to shut off when the big valve shut off. Otherwise, it would always run a trickle and sound like the toilet never shut off.

 

[MarkB_MI]

TD, I don't understand your point. All the bladder does is to separate the air and water. Air above the bladder, water below it. When the tank is drained, air pressure causes the bladder to expand until air completely fills the tank.

 

[Geo-TH,In]

JeffB.
I even tried drilling a hole in the small tube to prevent it from sucking water out of tank. Still didn't work. I may try cutting tube. Mine trickled too, you could see it running down the side of toilet. Thanks
George