@CppGuy good article. In Australia we use air-conditioners to heat and cool. You can have central units that work best if cooling the entire house with all internal doors open for the return air flow. But most people have multiple split systems. We usually deal with a 10-15°C difference and don't need it on all day. Up north with 20+ difference they leave it on 24/7 across the entire house. Even putting a sheet up to cordon off a room helps to stop the load on an aircon.
@CppGuy the aircon will turn itself off but keep the fluid primed. You can also set your aircon to just remove the humidity and it'll help cool but use very little electricity.