Abstract
Additional retrofit on multi-room air-conditioner for LID rooms has been made in summer 2009, which could enable analyze macroscopic effect of energy conservation measures applied to a house of a low-rise residential building the author lives in. In spite of the lack of output measurements efficiency of high efficient air-conditioners was verified for rated operation but not for the very low-load operation. Energy saving effect of the window insulation could not independently be verified but comforts highly increased and analyses proved that total electricity consumption decreased by 28% in total. As the results, air-conditioner's running COPs are supposed high enough for cooling but considerably lower for heating.