Possible To Switch Between 2 Compressors For Air Con?

i got sys 3 and another sys for living rm. the sys 3 is 900 btu for 3 rooms and the other 1200. but most of time only use 900 btu one, i like to now if possible for air con tech to install a switch such that i can switch between using 900 btu one and 1200 btu one.

cos the 1200 btu compressor most of time is left unuse unless guest come visit.

i feel wasted since so poweful and also exp.