Adjust the switch for a pressure a bit below the highest pressure the pump can produce. Be wery wery careful not to touch any live parts with the wrench.
Well Pump Pressure Switch Replacement Ifixit Repair Guide
Well pump pressure switch sticking. Do not touch any part of the switch while it is energized. If it has tripped you will. Verify that your pump is creating enough pressure to signal the pressure switch to turn off. Check the water pump breaker in your electrical box to make sure the breaker hasnt tripped. What causes the contacts to stick. The contacts for the pressure switch for my well stick which causes us to lose water pressure i usually replace the switch once a year because of this but i just replaced the switch four weeks ago.
Pressure switch not turning off. Thats usually a symptom of short cycling or an electrical problem. If you are getting voltage to and from the control box and the pump is silent its time to pull the pump. The only thing you can really do without pulling the pump is to make sure you are getting voltage between the pressure switch and control box and from the control box to the pump. Check the well tank pressure gauge to see if it is at least 40. You can go to the well and listen for the whir of the pump.
Double check that power is running to your well and that there isnt a short. Allow the pump to fully cycle by opening a nearby water faucet. If the pump is not creating enough pressure to signal the switch to turn off it is possible the pump could need to be replaced. If the switch fails to close when the pressure drops the internal spring is bad. Google the switch manufacturer and see if you can get instructions for adjusting the pressure at which the pump shuts off. If the switch opens and closes it may have been temporarily stuck due to debris.
Here are a couple things to check.
Gallery of Well Pump Pressure Switch Sticking
