To provide a method for controlling an expansion valve for a multi-room type air conditioner in which room side expansion valve opening correction quantity can be correctly distributed in accordance with ability ranks of a plurality of indoor machines even when the ability ranks are different among the indoor machines connected in cooling operation and dehumidifying operation of a multi-room type air conditioner, and in which ability can be equalized by setting distribution of expansion valve correction values to be different between the indoor machine farthest from an outdoor machine and the indoor machine closest to it.
In cooling operation or dehumidifying operation, overheat degree of cooling medium sucked into a compressor is computed, temperature of cooling medium discharged from the compressor is detected, and total of expansion valve opening for all the indoor machines being operated is computed based on the overheat degree of cooling medium computed and the temperature of discharged cooling medium detected. Expansion valve operation quantity is computed based on heat exchanger overheat degree of each indoor machine, total of expansion valve opening increase/decrease is distributed in accordance with ability ranks in the respective indoor machine, and the expansion valve operation quantity is corrected based on the expansion valve opening increase/decrease distributed.
TAKEUCHI HIROYUKI
MARUOKA TOSHIYA
Masahiro Ishino
Next Patent: COOLING DEVICE, AND METHOD FOR COOLING