yes
Yes, in the form of GFCI circuit breakers, not as a receptacle.
Yes, Electrical supply stores usually carry them
Eight on a 15 amp circuit, tweleve on a 20 amp circuit, including the gfci receptacle itself.
You can't. The 120 volt GFCI is probably just a 2-wire (hot, neutral and ground) You would have to run a new 3-wire (2 hots, neutral and ground). The two hots are how you get the 240 volts (120+120=240). Also you must make sure the wire is gauged properly. #10 wire for 30 amps, #12 wire for 20 amps, etc.
yes
Yes, in the form of GFCI circuit breakers, not as a receptacle.
Yes, Electrical supply stores usually carry them
Eight on a 15 amp circuit, tweleve on a 20 amp circuit, including the gfci receptacle itself.
You can't. The 120 volt GFCI is probably just a 2-wire (hot, neutral and ground) You would have to run a new 3-wire (2 hots, neutral and ground). The two hots are how you get the 240 volts (120+120=240). Also you must make sure the wire is gauged properly. #10 wire for 30 amps, #12 wire for 20 amps, etc.
no
yes
A volt can not be connected to a circuit.
A GFCI outlet has a TEST and RESET switch. Press reset and see if it fixes problem. If reset won't stay in that means that a ground fault condition is present and may be on another outlet that is fed from the tripped GFCI. If this isn't the problem check the main breaker feeding the GFCI and ensure it isn't tripped. If none of this works the GFCI itself may be bad. If you have a Volt Meter you can remove the outlet from the wall receptacle and make sure there is voltage present. You can also see if there is a branch circuit connected. To troubleshoot you can disconnect the branch circuit and then try reset. If you have voltage on input and GFCI won't reset with branch circuits removed, replace the GFCI.
Yes you can but the electrical code does not require it. To use one where it is not requested to do so is just adding to the over all expense of the project.
A load of 1600 watts should be placed on a 20 amp 120 volt GFCI outlet.
You need a breaker rated for 10 amps and 250 volts. The breaker must also fit properly in your panel.
The current will remain in a 220 volt circuit as long as the circuit load remains in the circuit and the circuit remains closed.