Air bubbles in drinking water

[challengertn]

My parents have a well and the water has a lot of fine bubbles in the water that dissipate after a time. He has a submersible pump with the tank in his basement. He recently added some more air to the tank and I think this is the problem. We turned the pump off and ran a lot of water out of the tank and the air was no longer there. My question is, would it be okay to drain the tank completely to get the air out and start over?

 

[johndeere2210]

Most pressure tanks are designed to operate with a certain amount of air pressure in them. When they loose air, the tank goes into a condition called "water logged". This condition is not good for the pump and will result in early pump failure. With no air in the pressure tank, the pump could run when ever a faucet is turned on and go off when the faucet is turned off, creating an on demand situation. Most pumps were not designed for this. I would not recommend draining the tank completely with out adding at least 20 psi air pressure when the tank is two thirds full. Just my two cents worth. /forums/images/graemlins/smile.gif The air bubbles you mentioned will not hurt anything.

 

[GerardC]

Look at it this way, your getting carbonated water for FREE /forums/images/graemlins/grin.gif. Gerard

 

[stevenf]

challengertn, Most pressure tanks actually have an air valve on them like a tire valve on the top and for sure what johndeere2210 said is good info. I'm not positive about the 2/3 full 20lbs thing but inside most newer pressure tanks there is a bladder water on one side air on the other after a while (years) the bladder will wear out and require a tank replacement. As far as the air bubbles I wouldn't sweat it either but do check your tank specs and make sure you have the appropriate air pressure as that is how water pressure is achieved by the pump pressurizing the air and then you have a high and low pressure switch that tells the pump when to come on and shut off. If your pump ran continuously it would last forever, pumps are mostly worn out by well running dry or the constant on and off because your pressure switch is set to close or bladder is worn out. If you have a jet pump its not such a big deal but if your pump is submergeable its a very big deal because in order to replace the pump you have to pull all the down pipe$$$$$$$$$$ compared to a little preventive maintenance on the top side mechanicals.
Steve

 

[BigAl]

The correct precharge on a pressure tank is 28 psi. That way ,as explained in a earlier post reply , the pump won't be coming on and shutting off so often . This is also known as a "hammer effect" and is not good for the pump . The new pressure tank design with a rubber bladder is the way to go . It comes precharged so you just hook it up and go . No air to add . I picked up a new one at Home Depot for about $180 .
Big Al

 

[LarryD]

I know tanks come with a pre-charge but there is a direct correlation between the Cut-In pressure and the charge on the tank. I had weak pressure at the house and called the installer to see about adjusting the pressure switch up. He said it wasn't a problem as long as the air pressure in the tank was about 5psi below CI pressure. You can't get an accurate air pressure with water in the tank so it has to be drained. Some manufactureres say 2psi below CI pressure so you might get in touch with someone who install equipment like you have.

As for the air bubbles, The pump can also generate those if it's not completely submerged. Do the bubbles appear before the pump kicks on (stored water), or after the pump comes on?