first did something happen to the forum I can't search any post past june of this year. where did all the old posts go?

ok so i am adding an programmable thermostat to my 240v baseboard heaters.
i am looking at the user guide
and it is calling for 2 wires only.

So one wire is hot and one is neutral i assume. But i have no idea how to get 240v out of one single wire.

I always used a double pole breaker and use a 12-3 wire to get 240v. but i got no idea how to get 12-2 to carry 240v. any suggestion? is there such of breaker that is 240 single pole?