A sump pump will normally have several switches attached to it and these sump pump switches are usually the pressure switch and float switch. It is also possible for there to be more sump pump switches built-in, but these switches cannot be replaced unless you send the pump back to the manufacturer. External switches however, such as the ones mentioned above, can be replaced by anyone with the proper tools. Generally speaking, you will require a screwdriver, replacement switches (Float and Pressure), paper, pencil and clean rags.
Make sure that before you start replacement of the sump pump switches that all of the plugs of the pump have been disconnected to make sure that they don’t turn on while you're working on them. It also avoids the possibility of electric shock which could injure you. You also need to disconnect the pipes connected to the pump
Removing the Sump Pump
Before you can remove the sump pump switches you must remove the sump pump from the pump basin. Since all the electrical and pipes have already been disconnected from the pump, it should already be free and you can take it out so you can work on it more freely.
Removing the Float Switch
Unscrew the sump pump float cap located at the top of the pump. Accomplish this by removing the screws that are holding it on. Use your screwdriver and undo all the screws until the cap comes loose. The cap will be covering some wires inside and you should take note how these wires are connected to the float switch. Make a diagram if necessary. Remove the wires from the float switch gently and take it out by removing the screws securing it.
Installing the New Float Switch
Clean the wiring from grime and dirt. Install the new switch where the old one used to go. Connect all of the wires, referring to the diagram you made. Replace the float cap and secure it with the screws.
Removing the Pressure Switch
The pressure switch is usually housed at the side of the sump pump. Open the housing covering the switch by unscrewing the screws holding it. Just like the float switch, you will see wires inside the housing and these wires are connected to the pressure switch. Take note once again where each wire goes and carefully disconnect them from the switch. When the switch is free, remove it by removing the screws holding it down.
Installing the New Pressure Switch
With the old pressure switch removed, clean the wires of any dirt and grime that may have accumulated on them. You can just use clean rags to wipe them off. You can also use contact cleaner to be more thorough. Install the new pressure switch and use the screws you removed from the old switch to fasten it into place. Plug in the wires where they should go, referring to the diagram that you made. You have now just changed your sump pump switches.