How to Set the Pressure on a Well Pressure Tank

Things You'll Need

  • Bicycle gauge

  • Air pressure pump

  • Phillips screwdriver

Setting the pressure in a water pressure tank is very important before installing the tank. The tank pressure must be lower than the switch pressure. This has to be done manually before installing the tank.

Setting Pressure in a Pressure Tank

Step 1

Shut off the breaker and unplug the tank from the wall. Shut off the gas if it is a gas tank. Locate the pressure switch, which is next to the pressure gauge. Remove the cover with a Phillips screwdriver. There are two screws located on each side.

Step 2

Locate the pressure switch limits, which are located inside the pressure switch cover. Pressure switch limits are different on different types of pressure tanks, such as 20 to 40 lbs.psi, 30 to 50 lbs. psi, and 40 to 60 lbs psi. The lower number is the turn-on point for the tank to bring in more water, and the higher number shuts the pump off. If you cannot locate the sticker that says the cut-off limits, then you will have to lower the pressure.

Step 3

Use the bicycle pressure gauge and put it on the air release valve. This will let some air out, and it will also tell the pressure in the tank. All new tanks come with a certain level of pressure already in the tank. The small and medium tanks have 28 lbs. psi, and larger ones have 38 lbs. psi. Lower this pressure by allowing the gauge to release air from the tank.

Step 4

Lower the air pressure to 26 to 28, since most above-ground tanks have a pressure switch that operates at a turn-on point of 30 lbs. psi and a turn-off point of 50 lbs. psi.

Step 5

Plug the tank in and turn on the breaker. Replace the cover for the pressure switch.

Step 6

If the tank does not kick on at 30 lbs. psi, then you will need to get a air pressure tank. Unplug the tank and turn off the breaker. Place the nozzle on the nozzle that you put the bicycle gauge on. Fill the tank up to 36 lbs. psi. Plug the tank back in, and turn on the breaker.