PC9 + uses DC inverter technology (cold is fast and stable), with remote control. to be able to set the Temperature, equipped with a timer and fan speed control. PC9 + cooling power is 125m3 / hour higher. cooler faster (less 1.5min). Air flow is also faster than 12 ft / sec.
while pc 9 don’t have remote and not yet use the inverter system. The cooling system is automatic, just plug to electricity, lift both deflectors and it can be used immediately. just practical.