The most common mistake when buying an air conditioner is guessing, or choosing by price alone. A unit that’s too weak won’t handle the heat; one that’s too powerful cycles on and off too often.
A simple formula
For a room with normal insulation and ceilings up to 3 m: roughly 1 kW of cooling power per 10 m². A 25 m² room needs about 2.5 kW (the 9000 BTU class).
Quick reference by area
- up to 15 m² — 5000-7000 BTU
- 15-25 m² — 9000 BTU
- 25-35 m² — 12000 BTU
- 35-50 m² — 18000 BTU
What else to check
An inverter compressor is more economical, and an A++ energy class or higher noticeably lowers electricity bills with regular use.
The full range is in the elis.ge air conditioner catalogue, including the MAYER TAC-07MN1 7000 BTU.
