Can you use 240-volts with a 120-volt supply?

Answer 1

This is not possible because a 120v switch disconnects one conductor while a 240v application requires that both hot conductors be disconnected simultaneously. The proper solution is to use a double pole 240v switch of the correct size. It must have contacts which are rated to carry the appliance's starting and running currents (amps). A switch with under-sized contacts would be likely to get very warm - or even overheat - to such an extent that it might become a dangerous fire hazard. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB

SAFELY AND COMPETENTLY

REFER THIS WORK TO QUALIFIED PROFESSIONALS.

If you do this work yourself, always turn off the power

at the breaker box/fuse panel BEFORE you attempt to do any work

AND

always use a meter or voltage indicator

to insure the circuit is, in fact, de-energized.

Answer 2

Yes if you have a step up transformer. Primary voltage 120 volts, secondary output voltage 240 volts.

Answer 3

Yes, the rating of 250 volts on the switch is the maximum voltage that can be applied to the switch.