Quote:Is window/wall units more common in the north east? Around here it is closer to 80/20 in favor of central cooling.

Yes.  In and around the urban and many suburban areas there are a larger amount of small apartments, flats, duplexes and cottages.  The smaller square footage lends itself to the cheaper AC units.

 

 Also - the "dog days" are scattered between a 2 or 2.5 month period. Rather than the 4plus month stretch in the south.  So they are used for as little as half as much each year. 

 

In areas that are at higher elevation north of NYC - some apartments and houses can still be found without AC at all. Although that isn't as common as it was 15 years ago.  

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