What is the range of air pressures in a small household water holding tank?

you will need to turn water on in house and see where the tank pressure drops to before pump starts up if [eg 30 psi] youre tank pressure should be set 2 pounds less [28psi]. you have to turn off pump and turn a faucet on to drain all water from tank before changing air pressure.the pump switch cover inside might give you the low [cut in] pressure.start 2 pounds less than that.