Well with Air Volume Control instead of Bladder Tank

[Travelover]

I recently bought a house with a well and I'm getting to know the system. It has a conventional pressure tank set up but uses an air volume control instead of a bladder in the tank. I replaced the controller and as a result let all the air out of the tank. Now that I have replaced the controller, it is short cycling.

My question is, do I need to do anything to put air back into the tank or will it automatically replace the air by itself. If so, how long should it take? It has no Schrader valve like a bladder tank.

This site explains how these work. I have a US Gauge WJ controller.

 

[ultrarunner]

I have owned property with only captive air and no bladder.

Every couple of months I would have to charge the tank... add air.

What was a chore became so much easier with my air chuck and compressor.

Short cycling is hard on the system... not the end of the world but shortens life of components.

 

[Travelover]

I have owned property with only captive air and no bladder.

Every couple of months I would have to charge the tank... add air.

What was a chore became so much easier with my air chuck and compressor.

Short cycling is hard on the system... not the end of the world but shortens life of components.

Right, I get that. This system has a device that keeps the air volume in the tank at a certain level - it is described in the link in my initial post. My question is to those familiar with the system, how fast it reaches a correct air volume on its own.

 

[mrmikey]

As UR said, an air compressor is the easiet but if you don't have one to get you out of a pinch, drain all the water out of your tank and let it fill back up again. It'll create a head of air at the top...........Mike

 

[gary49]

You don't state how big your tank is, but if it was mine, I'd replace the tank with a bladder type tank and be done with it. Much simpler and more reliable. The air volume control or "snifter" valves that I'm familiar with do have a Schrader valve for adding air, not sure why yours doesn't. There should be an inlet valve with a check valve which adds air to the system each time the pump cycles off, this is frequently down the well at the top of the casing, but the whole thing is just a PITA compared to the bladder tank system. If you do still have a functioning air inlet valve you'll need to plug it or remove it if you change to a bladder tank.

 

[ultrarunner]

The old tanks only need you to drain the tank to let air in and then fill to about 60% with water.

My brother had one for years... it had a valve on the tank about midway up... after draining the tank he would fill until water started to come out the midway up valve and then close the valve... trapping or capturing air in the tank.

It was something that would need doing every so often as the volume of air diminished...

The tanks with bladders are a maintenance free version of the old style... pressurize it once and be good for years.

 

[wagne223]

Cant help you with the system you have, but I'll say this......

No matter the type of tank on your well, it will periodically need to be replaced. Even the bladders become waterlogged.

If I were you, i would abandon the air injection/regulating system and replace it with the largest bladder tank you can find.

Cycling is what wears out switches and pumps. Larger bladder tank, fewer cycles, the longer your pump will last.

 

[Travelover]

You don't state how big your tank is, but if it was mine, I'd replace the tank with a bladder type tank and be done with it. Much simpler and more reliable. The air volume control or "snifter" valves that I'm familiar with do have a Schrader valve for adding air, not sure why yours doesn't. There should be an inlet valve with a check valve which adds air to the system each time the pump cycles off, this is frequently down the well at the top of the casing, but the whole thing is just a PITA compared to the bladder tank system. If you do still have a functioning air inlet valve you'll need to plug it or remove it if you change to a bladder tank.

Thanks. It sounds like you are familiar with the type of system I have. I think I'll add a T fitting and a Schrader valve for now. When the time comes, I'll replace it with a bladder tank. The air volume control was working perfectly until I replaced the pump switch.

 

[CobyRupert]

My mom has a deep well jet with a (non-bladder) pressure tank, with no Schrader valve to add air. I'm going to put a new AVC on it this weekend, because they only seem to last 5 years. I'm going to follow this post, so if I'm all wrong, hopefully I find out.

I'd get as much water out of the tank as I can before I "seal it" (trap the air) and add water. Remember Pressure x Volume (of the air) will be a constant. The volume (space) of the air decreases as the pressure increases. Initial pressure(P1) x initial volume of air (V1) = final pressure (P2) x final volume (V2) of air above water. So: P1 x V1 = P2 x V2

For example: When we start, after sealing up the tank, the gauge pressure in the tank is zero, (say 15 pounds absolute/atmospheric), and (say) the tank gets pumped up to 60 pounds (75 pounds absolute). We know the pressure has increased 5x, so the volume of air has decreased 5x.

If the tank is 48" high and empty of water when we seal it I think this means there will be about 9.5" of air above the water at 60 pounds. (9.5" x 5 = ~48")
If the pump then switches on at 30 pounds (at 1/2 of 60 pounds to keep this example simple) I think this means there will be about 19" (9.5" x 2) of air above water when the pump turns on, so you where able to extract 9.5" of water out of tank between cycles.

My understanding of a Air Volume Control Valve is that it only inserts a small bubble of air into the tank each time the jet pump starts to make up for air in the tank that has dissolved into the water. I don't have a good understanding on when this is too much or too little air to make up for what has dissolved. I would think this depends on how many times the pump starts versus how long the water sits there and can absorb air.

 

[robbyr]

My mom has a deep well jet with a (non-bladder) pressure tank, with no Schrader valve to add air. I'm going to put a new AVC on it this weekend, because they only seem to last 5 years. I'm going to follow this post, so if I'm all wrong, hopefully I find out.

I'd get as much water out of the tank as I can before I "seal it" (trap the air) and add water. Remember Pressure x Volume (of the air) will be a constant. The volume (space) of the air decreases as the pressure increases. Initial pressure(P1) x initial volume of air (V1) = final pressure (P2) x final volume (V2) of air above water. So: P1 x V1 = P2 x V2

For example: When we start, after sealing up the tank, the gauge pressure in the tank is zero, (say 15 pounds absolute/atmospheric), and (say) the tank gets pumped up to 60 pounds (75 pounds absolute). We know the pressure has increased 5x, so the volume of air has decreased 5x.

If the tank is 48' high and empty of water when we seal it I think this means there will be about 9.5" of air above the water at 60 pounds. (9.5" x 5 = ~48")
If the pump then switches on at 30 pounds (at 1/2 of 60 pounds to keep this example simple) I think this means there will be about 19" (9.5" x 2) of air above water when the pump turns on, so you where able to extract 9.5" of water out of tank between cycles.

My understanding of a Air Volume Control Valve is that it only inserts a small bubble of air into the tank each time the jet pump starts to make up for air in the tank that has dissolved into the water. I don't have a good understanding on when this is too much or too little air to make up for what has dissolved. I would think this depends on how many times the pump starts versus how long the water sits there and can absorb air.

Those math equations are interesting. Never thought about that. My late father in law pulled his pump 18 years ago and replaced it with a second line of pvc to blow water up using his air compressor. Water is blown into 1000 gallon concrete tank. Float switch in this tank activates some kind of valve that lets air in the well. Jet pump then pulls it to the old galvanized pressure tank. There’s no snifter to push air into pressure tank but there is a valve there to pump some into it.