1. BTU eka depend wenne umbe room eke condition uda. ceiling height / door and window leakages wage dewala balapanawa. (window size wage dewal umbata echchara adala ne reata witharak nisa) Thumb rule ekak widiyata 1 ton for 150 sq.ft ganin. 13x16=208 sq.ft. 18,000 BTU ekak hondai. 12,000 BTU th...