Most mini-splits have their thermometer near the top of the indoor "head" unit, which allows them to read the temp of the return air. But that return air is often not the temperature of the room air in, say, the middle of the room, 3-5' off the ground. Only a few higher-end brands and models make use of a thermostat in the remote or other (remote) sensor. So, basically, you figure out what temp setting feels good during a given season, and leave it at that, even when that temp seems like it would be way off if it was the setting for a typical wall thermostat.
We have three buildings with mini-splits (two Daikin and one Mitsubishi) and they all exhibit this behavior. Example: We set the BR unit to about 66 to keep the temp at 70, and at 68 to achieve the same temp in the Living Room. In the guest house, 70 keeps things at 72 in the living room, but the bedrooms tend to stay very close to their set temp, probably because those indoor units are wall-mounted at floor level. Bottom line: Figure out what temp setting feels right to you for each indoor unit, and use that, largely ignoring the number itself.
We have three buildings with mini-splits (two Daikin and one Mitsubishi) and they all exhibit this behavior. Example: We set the BR unit to about 66 to keep the temp at 70, and at 68 to achieve the same temp in the Living Room. In the guest house, 70 keeps things at 72 in the living room, but the bedrooms tend to stay very close to their set temp, probably because those indoor units are wall-mounted at floor level. Bottom line: Figure out what temp setting feels right to you for each indoor unit, and use that, largely ignoring the number itself.
