1- The energy will be wasted unnecessarily.
2- Cost of the unit will be higher than required.
3- Cost of installation will be higher since a bigger unit will need a bigger ductwork, a bigger pump, and a thicker power cables etc.
4- The compressor will interval (will be switched on an off) very frequently and this will result a shorter life expectancy.
5- The humidity removal function will not work as expected. The humidity level may even be increased.
6- The users will be disturbed because of the temperature level is changing up and down very fast (especially during sleeping). They may even get sick.