MoonAir guide
How to choose air cooler size by room area
Start with your room dimensions, local humidity and a path for fresh air. Then check the exact model’s airflow before choosing a tank size.
Quick answer: room area is a starting point
There is no reliable litres-to-square-feet rule for choosing an air cooler. Tank capacity describes water storage, not verified room coverage. For a useful shortlist, measure the room, note its ceiling height, check ventilation and compare confirmed airflow for the exact models. A domestic or commercial label alone does not establish whether a cooler will suit your space.
Measure floor area and room volume
For a rectangular room, floor area = length × width. Room volume = floor area × average ceiling height. A 15 ft × 20 ft room is 300 sq ft; at a 10 ft ceiling it contains 3,000 cubic feet of air. At a 12 ft ceiling, the same floor area contains 3,600 cubic feet, 20% more volume. These are room measurements, not a cooler capacity recommendation.
Also note connected open spaces, direct afternoon sun, people and heat-producing equipment. Share the layout with the manufacturer rather than choosing from floor area alone.
Check humidity and an outlet for moist air
Direct evaporative coolers work best in dry heat and add moisture to the air. Plan a fresh-air inlet and an outlet through an open window, door or suitable vent, following the model’s instructions. A fully sealed room is a poor fit. Higher humidity limits evaporation; choosing a bigger tank does not solve that limitation. If you need humidity control or a set indoor temperature, consider whether air conditioning is more suitable.
Compare airflow separately from tank litres and air throw
Air delivery is a volume of air moved over time. CFM means cubic feet per minute; m³/h means cubic metres per hour. Compare ratings in the same unit: 1 CFM is about 1.70 m³/h. Air throw describes distance and cannot replace an airflow rating. Ask which fan setting and test conditions a rating applies to, and whether any room-coverage figure is measured, manufacturer-recommended or only an estimate.
Tank size helps you plan water storage and refilling. Actual refill intervals also depend on weather, fan and pump use. Neither a tank size nor an airflow number alone guarantees comfort in your room.
What should you choose for a 300 sq ft room?
Do not select 125L, 150L or another tank size from 300 sq ft alone. Start with the 15 ft × 20 ft example above, add your actual ceiling height and identify the air inlet and outlet. Then ask MoonAir to confirm a suitable model using its airflow, your climate and the room layout. Before buying, also check placement dimensions, access for cleaning and refilling, and noise at the speed you expect to use.
Useful details to send: room length × width × height; city and typical humidity; window and door positions; sun exposure; people or equipment; daily operating hours; and where the cooler can stand.
Build a MoonAir shortlist and confirm the specifications
Browse the domestic and commercial ranges, then inspect the exact model and variant. Mahaveer 80 XP and MahaBali 120 XP are examples to compare, not recommendations for every 300 sq ft room. Confirm airflow and any stated coverage before buying. The room planner accepts room area, ceiling height, climate and ventilation. It calculates room volume and prepares a checklist, not a site assessment or a cooling guarantee.
FAQs
What cooler is good for a 300 sq ft room?
Room area alone cannot establish the right model or tank size. A 300 sq ft room with a 10 ft ceiling has a volume of 3,000 cubic feet. Check local humidity, ventilation, heat sources and the exact model’s airflow, then ask MoonAir to confirm suitability. Do not treat 125L or another tank capacity as proof of coverage.
Does ceiling height matter?
Yes. Multiply floor area by average ceiling height to find room volume. A 300 sq ft room contains 3,000 cubic feet at a 10 ft ceiling and 3,600 cubic feet at a 12 ft ceiling. That difference matters when assessing airflow, but does not by itself specify a tank size.
Does a bigger water tank mean more cooling coverage?
No. Litres measure stored water, not the volume of air moved or verified room coverage. Check airflow, ventilation and climate separately. Refilling frequency also depends on operating conditions, so tank capacity alone does not promise a fixed runtime.
Can I use an air cooler in a closed room?
Direct evaporative cooling needs a path for incoming fresh air and outgoing moist air. Follow the model’s ventilation instructions. A fully sealed room or high humidity limits suitability; a larger tank does not remove those limitations.
Are CFM and m³/h the same airflow unit?
They describe airflow in different units. CFM is cubic feet per minute; m³/h is cubic metres per hour. Multiply CFM by about 1.70 to express it in m³/h, and compare ratings under equivalent conditions.