Air coolers are NOT recommended for high-humidity cities (Mumbai, Kolkata, Chennai, Goa, Kerala coastal areas). Here's why: How evaporative cooling works: Air coolers add moisture to air through water evaporation. This works great in dry climates (Delhi, Rajasthan, Gujarat, MP, UP, Punjab, Haryana) where humidity is 20-40%. Problem in humid cities: When humidity is already 70-90%, air cannot absorb more moisture. Result: The cooler blows hot, sticky air making rooms MORE uncomfortable than before. Alternative solutions: (1) Ceiling fans + cross ventilation, (2) Portable ACs (₹25,000-₹35,000), (3) Split ACs (₹30,000+), (4) Tower fans. Humidity rule: Air coolers work only when outdoor humidity is below 50%. Check your city's average humidity before buying.