Prior to operation, with the  tank, empty of water, the pressure should be 2psi below the cut-on pressure.  So, for example, with a 30-50 pressure switch (factory default setting), air pressure in the tank will equal 28psi.  If the pressure switch is adjusted to 40-60, the cut-on pressure will be 38psi.  Furthermore, always set the pressure switch to reflect a 20psi differential between cut-on and cut-off.  If the pump cycles too quickly causing the pump to cut on and off, setting the pressure switch to a higher on/off setting should slow down the cycling.  Remember to adjust the air pressure in the tank to reflect the new cut -on pressure.  Warning!  Most non-commercial tanks have a pressure rating of 100psi!

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