A hard wired home alarm system consists of a number of sensor plates connected to a control panel through a series of wires. You can disconnect a home alarm system that you no longer want to use by disconnecting the various components that are installed in the home and removing the wires. You don't need any electrical skills to disconnect a system.
Enter the proper access code to disarm the control panel. Unplug the power cord from the control panel so that electricity is no longer flowing into it. Remove the screws holding the front panel to the control panel's casing with a Phillips screwdriver -- if a locking latch requires a key to be used first, do so with the control panel key.
Disconnect the wires to the battery backup. Unscrew terminal caps with your fingers to remove the wires or pulling off battery tabs, depending on the make of the control panel. Remove the battery from the battery compartment and place it aside. Unscrew the terminal screw contacts inside the casing with the Phillips screwdriver. Unwind the wires wound around the contacts with your fingers.
Remove the screws holding the control panel casing to the wall with the Phillips screwdriver. Pull the control panel off the wall.
Open a window that has been hard wired to the home alarm system. Remove the screws holding the sensor plate to the bottom of the window using the Phillips screwdriver. Repeat this procedure with the sensor receiving plate that is screwed into the window sill.
Repeat the procedure with any other window that is hard wired to the home alarm system. Repeat the procedure with any door that is hard wired to the home alarm system, except the sensor plate will be on the bottom edge of the door and the sensor receiving plate will be at the bottom edge of the door frame.
Remove the staples that are holding the wires to the baseboard of the walls with the jaws of a needle-nose pliers. Dispose of the staples in the trash. Pull the wires through the walls and out of the hole that was behind where the control panel was. You can snip the wires with a wire cutters at strategic locations so that there's less wire to pull through the wall.
Unplug the power cord from an AC socket if the alarm is located inside next to the control panel and uses electrical power. If the alarm is situated outside and uses electrical power, first pull the appropriate fuse or trip the appropriate circuit breaker in the fuse box to discontinue the flow of electricity. Remove the screws surrounding the alarm with the Phillips screwdriver. Cut the wires off the back of the alarm with the wire cutters. Pull the wires into the house and seal the hole with silicone sealant, or fill the hole with wood filler. Restore the electric power.
The holes in the windows, doors, and walls can be covered up with wood filler.
You must cancel any subscription service that is in place to monitor your home alarm system prior to doing the disconnection.