New air conditioning system ideas for 100 year old single-family

[Mike Nelson]

I would like to have a new central air conditioning system installed for my 1,800 SF  100-year old single family victorian-style residence in Oak Park, IL.  The home is a two-story, with a full basement and a full attic.  Currently, the home has a good hot-water boiler-radiator system for heat located in the basement.  For cooling, we rely on seven window unit air conditioners and free-standing window units.  It is an annual back-straining exercise to remove and install these units every year.

My thought is to go with a high velocity system with 2" diameter tubes for distribution.   There would be one or two air handlers and condensers.  I hear the term "SpacePak" around the neighborhood.  Apparently this is a brand name, there are competitors.  Are there any ideas on solutions, as far as types of solutions at the most reasonable cost?  Is there a less expensive time of year to have this done?  

[Jaron Walling]

@Mike Nelson I'd do research on Mini Split systems. A mini split air conditioner has indoor and outdoor components, but it takes up a lot less space than traditional HVAC. It's basically a tiny version of a central HVAC placed in various rooms. You can run zones in the house and cool the most active rooms in the summer. 

Another difference is that it doesn't rely on ducts to deliver heated and cooled air. It's a great option for older historic homes with limited space.