Friday, May 15, 2015
Can I Increase My Pressure Tank Size To Use It As A Contact Tank?
If I increase my pressure tank size to 86 gallon can I use it as a contact tank?
Thank you for contacting us through our website.
Well, not exactly. You could certainly try it and it would certainly be better than using a much smaller pressure tank, but compared to a contact tank the results are less consistent.
With a contact tank, all of your water enters in through the bottom and exits out the top, no matter what, so you’ll always get that minimum amount of retention allowed by the contact tank size.
With a pressure tank, on the other hand, even with a large pressure tank, the household water doesn’t necessarily always enter the pressure tank. And even the water that does enter the pressure tank isn’t guaranteed to properly mix or stay in there long enough to guarantee mixing time, since the water enters and exits through the same port.
In short, if you rely on a pressure tank for contact time, then you would get adequate mixing some of the time but not all of the time. What are you looking to do with chlorine, are you trying to kill off bacteria, or are you using it to oxidize iron, or eliminate odors, etc.? Generally for bacteria treatment, it is critical to have the contact tank, but otherwise you may be able to try it without first.
Below is a visual representation of what is described above.