Thanks for the response. Would you put the single unit in the LR or the DR for max circulation between the three rooms?

One of my concerns is that if a one 14000 BTU unit fails, I'm out ~$600, whereas if one of the 8000 BTU units fails, I'm out ~$300 (unless they both fail). Should I expect material energy savings with one inverter A/C unit over two non-inverter units?

People customarily put window units in area where they spend the majority of time during daylight hours. Your concern for dining and kitchen causes me to ask if you spend more time in there than average? You'll need to compare energy consumption to answer questions about operating costs.

Window units don't distribute air very well. They aren't effective in large areas. Generally they cool a single room. I'd go with an individual window unit for the LR and one for the DR..

I live on the 12th floor of a 1930's building in NYC. It gets HOT! We purchased a large LG inverter unit last year. (I don't remember how many BTU's!) The thing is incredible. So quiet and actually does a great job of cool multiple rooms. We certainly don't need one for our living and one for our dining.

I love the dry setting. Pulling moister out of the air is half the battle. I keep it on dry as much as possible and then blast it on cool mode every once in a while. I'm sure other AC nerds on here know better than me about how much energy dry mode uses vs cool

Do you have blinds or shades and do you keep them cool as much as possible?

Do you have a storage area where the window units can live off season? The size of the storage might help you decide whether to get one or two units.

Thanks for the considerations. @Kendrah - any idea how much square footage your unit is cooling today? Is your layout similar to mine? I'm mostly concerned that one large unit would do a good job at probably 2 rooms but neglect the third (either all of my kitchen, or part of the LR).I do have shades in most spots - my main tactic is to use a box fan to bring cold air in during the evening, which honestly works pretty well as long as it gets cold enough at night.

Storage shouldn't be a huge issue, I have full access to the basement and/or attic.

Upper in a duplex means you could have access to attic space for an easy ductless heat pump. You decide how many zones you want.

Sorry for the delay. Here is a layout of my apartment. The big LG AC is in the window with the pink star.

What helps - we close the door to the bedroom and have an AC window unit with fewer BTU's in there.

We have pocket doors to the kitchen. We sometimes keep them closed to contain the air more in the living space. Other times we keep them open so the AC window unit can cool that room too.

It is whisper quiet and again, I use the dry most as often as possible.

We have a beautiful view from the living room and didn't want an AC unit covering that window. We thought we would be sacrificing coolness by placing it in the dining room but are quite surprised that the entire living room is cooled by one unit that is not in direct line with the opening of the space. I think it is 12k BTU but cannot remember and I'm not at home.

The "Dry" setting on a window unit doesn't do anything more than force the circulation fan to operate on low speed, which makes the unit cool more slowly (reduced air circulation) so the compressor runs longer to reach the target temperature.

We don't set a target temp when we turn on the dry function. It is not cooling the air as much as it is removing the humidity like a dehumidifier would do. When the air is less humid, it feels less oppressively hot. I live in a location with a very high humidity index. Maybe it doesn't make sense for someone in a dry climate. I love it because I feel cooler without the chill that comes with running it on AC mode.

From Angie's list:

"Dry mode on an air conditioning system reduces humidity levels in the air without excessively cooling the room. When you switch your AC to dry mode, it functions primarily as a dehumidifier. Unlike the traditional cooling mode, where the AC unit runs continuously to lower both temperature and humidity, the dry mode only focuses on removing moisture from the air.

In this mode, the AC's compressor and fan operate at a lower speed, allowing the unit to draw moisture from the air more efficiently. Once the desired humidity level is reached, the compressor may cycle on and off to maintain it, ensuring a comfortable environment without overcooling."

That quote from Angie is an extreme simplification, and disregards some fundamentals about how air conditioning works.

I live in Texas, two counties in from the coast in the Houston region. I prit'much understand humidity and air conditioning.

All air conditioners cycle the compressor on and off per the thermostat setting.

A true stand-alone dehumidifier is designed differently than a (cooling) air conditioner such as a window unit. Stand-alone dehumidifiers have the condenser coil (the outside part of a window unit that gets warm/hot) positioned inside the room (the entire mechanism of a stand-alone dehumidifier is inside the room) such that the airflow path is through the evaporator (which cools the air and removes moisture as part of the cooling process), then through the condenser which rewarms the air. A stand-alone dehumidifier will in fact slightly increase the room temperature due to the heat generated by the compressor and circulation fan motors.

Is there a humidistat on your window unit by which you are setting a desired percentage of humidity?

There were window air conditioners many years ago that could function as a true dehumidifier, without cooling, with a secondary condenser coil and both a humidistat that functioned in dehumidification mode and a thermostat that functioned in cooling mode. I'm not aware of any nowadays. Perhaps you can provide the model number of your air conditioner so I can research if perhaps there IS such a unit nowadays?

In practice the most important thing is whether consumer is satisfied with his air conditioner. The human mind is a wonderful thing and skill in making it happy can make a world of difference. Mom served home made ice cream on hot Sunday afternoons and strawberry was the majority favorite. There were often remarks about the need for more berries until one Sunday everyone commended mom for the abundance of berries in the cream. After everyone finished mom told us the only difference was a few drops of red food color.