Sensor was found ok cleaned and refitted. Results did not change. And later experimentation with other Inverters disclosed same results. That is the reason I have given summary of Inverter performance few posts above that how it becomes energy saving when it dips below 5 amperes only. Plus the fact that inverter sacrifices on cooling performance slightly taking the benefit of body's adaptation to temperature and sqeezes energy conservation.
Given your Haier 1.5 ton working as explained by you we need to see the amperage throughtout the night as you said it maintained the remote set temperature. Some OEMs have lower energy consumption and some have tighter temperature conservation as set by user but they spend more juice to do the job that way. Its a trade off. In my case remote temps from 24 till 28 are energy conservative while 23 and below till 16 are performance oriented incase you want to test the might of compressor.
Also, the temperature gauge should measure saturated temperature in the room and for that you have to switch the ceiling fan off and place thermo out of the way of AC throw completely. Better place it in an opposite corner of room other wise it will pick cold spots which are in frontal area of AC throw.
