If everybody starts doing that, we get into a vicious circle of more and more carbon dioxide;

Globally, we use a lot more energy to heat spaces than to cool spaces. And installing air conditioning units in a lot of places will actually reduce overall energy use and fossil fuel consumption/CO2 emissions, because air conditioning units can be reversed and act as heat pumps that are 3 to 5 times more energy efficient than combustion at heating any given space.

Europe and North America, especially, need to switch as many heating systems as possible over to heat pumps. That will make things more comfortable and safer, while also reducing overall annual energy consumption.