Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Kousuke Tanaka

Takashi Ikeda

Osamu Morimoto

Fumitake Unezaki

Masaki Toyoshima

Yasutaka Ochiai

Hiroshi Sata

Tomotaka Ishikawa

Kouji Yamashita

Yasunori Shida

Masahumi Tomita

An air conditioner includes: a heat source-side unit having a compressor, a heat source-side heat exchanger, a first throttle device and a super-cooling heat exchanger; a load-side unit having a second throttle device and a load-side heat exchanger; a switching device for switching connections of discharge and intake sides of the compressor between the heat source-side unit and the load-side unit; a refrigerant reservoir supplying refrigerant and connected to a refrigerating cycle between the first throttle device of the heat source-side unit and the heat source-side heat exchanger through a refrigerant filling switch valve; and a controller controlling the switching device, the first throttle device, the second throttle device and refrigerant filling switch valve.

Air conditioner, refrigerant filling method of air conditioner, method for judging refrigerant filling state of air conditioner as well as refrigerant filling and pipe cleaning method of air conditioner

An air conditioner is arranged so as to be able to accurately judge a refrigerant filling state within the air conditioner regardless of environmental and installation conditions. The air conditioner has a computing sectionfor computing a condenser liquid phase area ratio that is a value related to an amount of liquid phase portion of the refrigerant within a high pressure-side heat exchanger, based on refrigerant condensation temperature of the high pressure-side heat exchanger, outlet super-cooling degree of the high pressure-side heat exchanger, intake air temperature of the high pressure-side heat exchanger, a difference of enthalpy of inlet and outlet of the high pressure-side heat exchanger and specific heat at constant pressure of a refrigerant solution at the outlet of the high pressure-side heat exchanger and a judging sectionfor judging the refrigerant filling state within the air conditioner based on a comparison of the value computed by the computing sectionwith a predetermined value.

By studying or storing refrigerating cycle characteristics of an air conditioning apparatus at the normal time and comparing them with refrigerating cycle characteristics acquired from the air conditioning apparatus at the time of operation, it becomes possible to exactly and accurately diagnose normality or abnormality of the air conditioning apparatus under any installation conditions and environmental conditions, which eliminates operations of inputting a difference between apparatus model names, a piping length, a height difference, etc at the time of apparatus installation. Accordingly, it aims at shortening the time of judging normality or abnormality, and improving the operability. It is characterized by calculating and comparing a measured value (a value of liquid phase temperature efficiency &#x3b5;(SC/dT) calculated from temperature information) concerning an amount of a liquid phase part of the refrigerant in the high-pressure-side heat exchanger with a theoretical value (a value of liquid phase temperature efficiency &#x3b5;(1&#x2212;EXP(&#x2212;NTU)) calculated from the transfer unit number NTUat refrigerant side).

Air conditioning apparatus

Growing community of inventors

Tokyo, Japan

Kousuke Tanaka