How do the constant speed units operate?

The constant speed air conditioning units are the units that have constant speed compressor. These compressors regulate temperature with the same speed of the electromotor that rotates them and it is steady (so it is their power) independently of the cooling/heating loads that the air conditioned rooms need. So, either they will be operating at maximum capacity or switched off entirely. When using units with constant speed compressor, the control of the temperature in the rooms is done by using ON/OFF thermostats.