Hitachi Appliances, Inc

Hitachi Global Life Solutions, Inc.

Norikazu Sasaki

Hideo Tomita

Hiroshi Kusumoto

Eiji Ogata

Keiko Oka

Kazuhiro Tsuchihashi

Yoko Kokugan

Yasuhisa Mori

Noriyuki Tokura

A refrigerant quantity diagnosis device includes: an evaluation value calculation part that calculates a refrigerant quantity index evaluation value including a ratio of a measured refrigerant quantity index value to a reference refrigerant quantity index value in each of a normal period and a determination period; and a refrigerant quantity diagnosis part that diagnoses a refrigerant quantity based on the refrigerant quantity index evaluation value. The evaluation value calculation part calculates a first refrigerant quantity index evaluation value in the normal period and a second refrigerant quantity index evaluation value in the determination period, based on respective reference refrigerant quantity index values having respective values associated with an operating condition of interest, and respective measured refrigerant quantity index values. The refrigerant quantity diagnosis part compares information on the first refrigerant quantity index evaluation value with that on the second one and thereby diagnoses the refrigerant quantity.

Refrigerant quantity diagnosis device, refrigerant system, and refrigerant quantity diagnosis method

A base terminal receives the air-conditioning control information from the server, and on the basis of the received air-conditioning control information, when a power consumption value in a site is greater than the target power value for demand control, the base terminal transmits, to air-conditioning control equipment, a control instruction that sets an air conditioner to OFF, and when the temperature measured in an area is greater than the upper limit temperature when the air conditioner is performing a cooling operation, or when the temperature measured in the area is less than the lower limit temperature when the air conditioner is performing a heating operation, the base terminal transmits a control instruction that sets the air conditioner to ON.

Air-conditioning control system and air-conditioning control method

Growing community of inventors

Tokyo, Japan

Norikazu Sasaki