My house started as a beach bungalow. The bedrooms, bathrooms (2), and laundry room all have 7' 2" high ceilings. The rooms are very small:
Master bedroom: 140.29 sq. ft., heavily shaded South and West facing windows with plastic faux wood blinds and curtains, R19 in attic above, no insulation below in vented crawl over sand
Guest bedroom: 78.375 sq. ft., 1 window facing east, just the plastic blinds, same insulation properties as the Master.
Dressing room is less than 100 sq ft., one window facing East and a second one facing South. Shaded and windows have blinds.
Guest bath is about 50 sq. ft., no external walls
Master bath is about 60 sq. ft., one West facing window, same blinds
Laundry room is about 50 sq. ft., one slider window facing North and is under a eve, same blinds
All of these rooms are connected by a common hallway that then pours out into our living room, a 268.75 sq. ft. room, 8' 5" tall ceiling with our front door facing West with a second small window on the same wall, and two windows on the opposite wall facing East. The living room has a opening into our kitchen, a ~320 sq. ft. space, again with 8' 5" high ceilings on a concrete slab, a sliding glass door facing West, a sliding window facing North and a double hung on the East wall in a stairwell that goes up to the second floor and has a door going to the backyard.
Upstairs are two rooms, 8' ceilings, separated by one door, the Eastern room has 3 windows facing East, and 2 windows facing South. The Western room has 6 windows facing West and two facing North. All have the plastic blinds. These rooms have a combined sq. ft of about 740 sq. ft. We have a portable 14,000 BTU unit that does well cooling one room down, but the other room struggles (usually the one with all the Western/Northern facing windows) and since we don't occupy the space daily, we don't run this AC all the time - just when we anticipate being up there or it's insanely hot outside and we want the cat to feel comfortable while we're at work
Given all that
Here are the issues:
We put a 2 year old Sharp 8000 BTU unit in the Master Bedroom, set to 70*F, it gets clammy at night with the door closed, the humidity improves if we drop to 68*F, but then it's a bit cold and need to pile on more blankets. During the day, when we're at work we usually run this at 68-70, keep the door open and sometimes put a fan in the door-way to try and distribute the cool air through out. It definitely short-cycles. We often close the door at night to keep the bothersome cat out. It gets clammy and I feel gross, while the wife doesn't mind as much.
We also have an older 6000 BTU unit in the Guest Bedroom that we often leave on at 68-70, door open to aid in cooling the hallway and adjoining rooms.
We also have a 2 year old Sharp 12,000 BTU unit that we put in the East facing window in the kitchen and keep at 68-70*. This tends to cool the kitchen quickly and keep it and the living room comfortable.
So, the issues I'm trying to address:
On a per room cooling load calc, by the maths, the sleeping/dressing/bathrooms seem to require much less than 5000 BTU's each, 6000 max for the Master Bedroom and between 7-8000 for the living room, and about 12,000 for the kitchen (gas stove/oven).
All of the calculations work on a per room, compartmentalized theory. Central air, or better yet, mini-splits would be awesome, except that we don't have thousands of dollars to make either happen right now. I did reach out to a local AC installer and he came back with two estimates: one central estimate at and extremely expensive cost, and another for mini-splits at half the extremely expensive cost. My wife and I nearly fell over. I mean, if that's what it costs, fine, but we'll never spend that much money to do it. We'd sooner invest the money elsewhere in the house. So I'm stuck with window AC's.
I'd consider a self install of mini-splits with a AC pro check-out and system charging if the cost could be significantly reduced - if that's the long term answer.
So, I'm trying to figure out how to address the Master Bedroom clammy situation, but still have cooling power to keep that part of the house cool when the door is open.
I'm not sure how the cooling air flow works, if well at all given my layout, but there doesn't seem to be any intelligent information on the internet to advise on how to get the most out of a handful of window units to cool multiple rooms in some efficient manner or whatever manner could achieve adequate, non-damp comfort.
For now, I need some education and short term advise. Help?!?