Anyone who is getting their water from a well on their property knows how important a well pressure tank is. Well pressure tanks not only maintain the water pressure for the home but also serves as protection for the life of the well pump. The well pump delivers water into the pressure tank which compresses the air in the tank until it reaches the preset level which averages 40-60 lbs. psi.
When a faucet is turned on, the air pressure inside the tank forces the water out until the pressure has dropped to the preset level normally 20-40 psi. Once it reaches this level the well pump turns on to refill the tank to the restored set level. The amount of water that is delivered to the home before the pump turns on, is called “the drawdown.”
The size of the pressure tank is determined by the amount of water that the well pump can draw in a 1-2 minute time frame. Well tanks come in various sizes with small ones being only 10 gallons and larger ones up to 200 gallons. The average home will use a tank that holds about 44 gallons with a 16-gallon drawdown.