I was responding to the point about using AC all year to remove humidity. The thermodynamics works like this: The air inside your house is more humid than the air outside; warm air at the same pressure holds more moisture than cold air. When you extract the warm air from the house the heat exchanger cools it down, therefore reducing its moisture carrying capacity and causing condensate to form which you can remove. The heat is transferred to the incoming cold air via the heat exchanger, the warmed up incoming air now has a much greater water carrying capacity even if it was already humid outside so it absorbs humidity from your house, when this air is extracted again the cycle repeats. Passive houses have very low humidity inside because of this.
> I was responding to the point about using AC all year to remove humidity.
That's not something I claimed.
Most people in the US are only using AC in the summer (or warm season), to remove humidity from their home when the humidity outside is much higher than indoors.
Sorry I was confused when you said “if not for the heat then to at least remove the moisture”. When your insulation is being used to keep heat out, your heat exchanger would operate in reverse to use extract air to cool incoming air, some MVHR units have optional precooling of incoming air. I expect a modern standard AC unit will be doing some cold recovery as well to improve efficiency. But ideally a fabric first approach will keep a lot of heat out when combined with external blinds and brise soliel to keep high angle summer sun out.
