My house has an existing forced-air heating system and I'm looking at getting central AC added in a few weeks' time (indeed, I've booked contractors for estimates next week). An AC system would keep my house cool when it is hot outside.
...but what options are there for cooling a house when it's also cold outside (without running expensive AC)? I don't like having to manually open windows, so I was wondering if there was some kind of additional cooling system which sucks in cool air from outside and blows it through the forced-air ducts, thus cooling down the interior without needing to run AC.
...does such a system exist? Do AC systems do this anyway?