Water pressure for water-well installations is maintained by a pressure tank installed in the line between the well pump and the residence.
Pressure to the tank is regulated by an electric switch that turns the pump on when pressure is low and off when the proper tank pressure is reached. The pressure switch may require periodic maintenance.
Before performing any maintenance steps on a pressure switch, turn off the power to the switch. The current required to run a well pump is potentially deadly. Open your breaker box and look for the breaker marked "well" or "pump." It may be a single large amperage (30 amp or more) breaker or two lower amperage breakers in tandem. If you're not sure which breaker is the right one, turn off the main breaker to the house. (Do not leave the main power to the house off for periods long enough to defrost frozen foods or reduce the heat long enough to freeze pipes.)
If maintenance steps do not return the pump to service, replace the switch.
An hour or so to perform routine maintenance and reset pump pressure switch
Screwdrivers, emery cloth, pliers, small open-end wrenches
Cleaning electrical contacts
Shut off power to the pump.
Turn off the power to the well and locate the pressure switch. It is likely to have some kind of plastic or metal cover secured with screws. Unscrew them and lift off the cover. Set it aside so it won't get damaged. (The easiest thing to do in a cramped well house is to step on a switch cover.)
To clean the pressure switch contacts, slide a length of emery cloth between them and pull the cloth across them several times. Reverse the cloth and repeat the process on the other side until all the contacts (usually eight or more) are shiny. Use pliers to unscrew an aerator from the end of a faucet spout and clean all the little parts. Replace the aerator if it is damaged.
Pressure switches are installed in conjunction with pressure gauges, and the switches are set to turn on at low pressure and off at a higher pressure (typically 20 and 40 psi, respectively). Adjustment instructions usually can be found on the inside of the switch cover. Use wrenches to turn the adjustment screws, following the manufacturer's instructions.