It’s hard to separate real A/C problems from passengers leaving their balcony doors open. There’s a sign on every balcony door to please keep the door closed. This is because even if you turn the thermostat way up, the system is still compromised and nearby cabins, particularly insides, are affected. Many people also keep their drapes open which heats up the cabin and strains the A/C with the effect similar to open balcony doors.