Use of waterlogged pressure tank

[citytransplant]

While I'm on subject of government bureaucrats... I trade NYS made knives as a hobby. I spent a few hrs. one Saturday at the kitchen table of the County Health Dept. guy in charge of inspecting septic systems. He had quite a collection of Camillus Cutlery Co knives for sale and I spent the afternoon pricing them so as to make an offer. We had an enjoyable time together talking knives and such.

I see him in the elevator at work (I was a "county worker" too) some time later and I tell him that I think a line in my drainfield must have failed and asked him for a possible solution. He responded with "I will come out and have a look."

Me thinks he's going to swing by on his way home from the office all unofficial-like. Instead he shows up in the middle of workday in County vehicle, clipboard in hand.

Had I not enlisted a septic guy who knew his way around the drainfield (read a farmer with a backhoe and a way with words) that elevator ride could've cost me tens of thousands. In hindsight I might've avoided the situation all together had I agreed to pay his inflated ask price for the knives.

 

[citytransplant]

I just had the "A HA" moment !!!

Kind of like when I first learned where babies came from and that Santa Claus thing the adults were trying to sell me.

It will take the same amount of time for the pressure to drop from cut-out (40 lbs in the case of my system) to cut-in (20 lbs) no matter the volume of water in the pressure tank(s). Therefore adding an additional non-pressurized tank beyond the operable pressure tank does not reduce number of cycles per hour, day, etc.

Man, I'm slow.
But I sure look damn good.

 

[kf4uda]

Cut that tank in half long ways and make a couple of feeding troughs for your goats. It will continue to serve you

 

[citytransplant]

Anything to distract them from chewing wires & hoses on my tractor.

 

[groundcover]

Or cut the top off and build a counter weight for the tractor !

 

[AnotherBueller]

If the bladder goes bad you can convert the tank to an old traditional captive air tank by adding air. At least you can't over-fill it. If you add too much air, the excess will just bubble out into the lines. It's a temporary fix to keep the pump from short cycling.

If you add air to a non-bladder water tank it will work untill the air becomes water logged (10% humidity), then it doesn't work and you'll have to open the high point at the top of the tank and let water fill it completely, drain the tank to let in dry air, close the top vent and refill the tank. What you've described is a non-bladder device to stop water hammer. Depending on the size they'll only last a few years and then you get water hammer again.
The only use you will realy get is as a water tempering tank to raise water from 55-60 degrees F to what ever to room is (ie" cooling the room)

 

[Valveman]

A water logged bladder tank will not add a volume of water to anything. Best to cut it in half and use as a watering trough as was suggested. While you are replacing your pressure tank it would be good to learn what causes the bladders to fail and make the tank waterlogged. Cycling on and off of the pump makes the bladder go up and down with each pump cycle. This is like bending a wire back and forth until it breaks. Eliminating the cycling of the pump not only makes the tank and everything else in a pump system last longer, but also delivers strong constant pressure to the house.

There are two ways to eliminate pump cycling. You can use a variable speed drive or VFD, like the Subdrive someone mentioned. These systems vary the speed of the pump to keep it from cycling on and off. However, these type systems are expensive and don't last very long, which is why they are so popular and promoted so heavily by some pump installers.

The other way, and best way to eliminate pump cycling is with a simple Cycle Stop Valve. These valves vary the flow from the pump without varying the pump speed, which eliminates cycling and delivers strong constant pressure to the house. With a Cycle Stop Valve a little 4.5 gallon size pressure tank is all that is needed, as the water is perfectly controlled and goes right past the tank anyway. The system doesn't know if it is a 1 gallon or a million gallon size pressure tank.

The variable speed type systems also use very small pressure tanks. But when these complicated and expensive VFD systems start giving problems and costing more money, many times they are replaced with Cycle Stop Valves.

 

[Larry Caldwell]

If you add air to a non-bladder water tank it will work untill the air becomes water logged (10% humidity), then it doesn't work and you'll have to open the high point at the top of the tank and let water fill it completely, drain the tank to let in dry air, close the top vent and refill the tank. What you've described is a non-bladder device to stop water hammer. Depending on the size they'll only last a few years and then you get water hammer again.
The only use you will realy get is as a water tempering tank to raise water from 55-60 degrees F to what ever to room is (ie" cooling the room)

Humid air is a real problem, just like the stale air in car tires. You have to deflate the tires and refill them with fresh air or your ride will suffer.

 

[Larry Caldwell]

The most common reason tank bladders fail is freeze damage.

 

[Valveman]

Bladders in tanks fail even more frequently in Mexico and Central America where it never freezes. That is because they commonly use much smaller pressure tanks than normal, which increases pump cycling and the number of times the bladder in the tank goes up and down.

Even in colder climates freeze damage to a pressure tank is rare. Being the tank is the largest part of the water system it takes MUCH longer to freeze than the pipe to/from the tank or the little nipple to the pressure switch. I have thawed out and repaired many frozen pump systems. When I get the frozen lines cut loose from the tank, the water in the tank is still liquid, squirts out, and gets me wet.

In the same way it is hard to freeze a cistern or storage tank because it takes a long time to freeze several hundred gallons of water. But the pipe to/from the cistern can freeze in a few minutes below 32 degrees.