Do I have to keep doors closed to keep the rooms which have RCACs at a comfortable temperature?

Do I have to keep doors closed to keep the rooms which have RCACs at a comfortable temperature?

Yes. You should keep all doors and windows closed as much as possible. Using thick curtains and external shading in sun-exposed rooms is also a great way to keep temperatures lower. If you have an open plan home, you might consider using a door curtain in hallways when you want to keep in warm or cool air.