Antifreeze I get the concentrated not the 50/50
My area recommends 50/50. But if at anytime you must add some and all you got is water then you don’t have to worry about not having enough antifreeze in the system. Yes they say water is better at getting out the heat out of the system. Maybe so just add some. Many years ago I believe many people ran strait antifreeze. But now I guess that is not good. But you must have some antifreeze for your air conditioning to work properly they say.