You are way beyond your abilities Grasshopper. You have several choices....

2 window shakers

A 2 cassette mini-split

A couple of years in school or vo-tech to design and install your own system

talk to a local HVAC tech

Before trying to use your existing unit, you need to know the capacity(btu) volume of airflow(cfm), fan curve charts, static pressures(design and measured), actual heat load(btu), current and desired RH, current and desired temperature, and a whole bunch of other stuff if you want to do it right.
Mississippi Steve Reviewed by Mississippi Steve on . 2 rooms - 1 AC im posting this in the advanced section mainly because i dont believe many people who arent 'advanced' would run a 2 room set up on a flip with AC and Co2 etc. i have seen many different ways of setting up a 2 room 1 AC system but i personally have no experience with 2 rooms 1 AC. this is why im here. 2 rooms. side by side. AC is water cooled unit. can AC be stationed in just 1 of the rooms but cool the 2 with a system of electric dampner units? what size dampner if so? 6"? 8"? what is Rating: 5