PURPOSE: To save energy by a method wherein low-power cooling or high-power cooling is selected according to the combinations of two kinds of conditions, i.e. whether outside-air temperature is above or below a predetermined temperature, and whether room temperature is above or below a set.
CONSTITUTION: Cooling operation is conducted in either one of two cooling control patterns A and B according as a outside-air temperature is high or low. Where outside-air temperature TO is above a predetermined temperature T4, a compressor motor is operated in a two-pole operation mode for high-power cooling when room temperature Tr is above a set temperature T1, but is operated in a four-pole operation mode for low-power cooling when Tr is below T1. Where TO≤T4, the control pattern B is conducted: low-power cooling is conducted when Tr>T1, but the compressor is stopped when Tr<T1. In the case of the control pattern A, the compressor may be stopped when Tr<T2 (T2 is an arbitrary set point). In the case of the control pattern B, high-power cooling may be conducted when Tr>T3 (T3 is arbitray set value).
YASUDA HIROSHI
KANOU MINORU
KAMESHIMA KOUJI
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