AIR CONDITIONER

摘要

PROBLEM TO BE SOLVED: To prevent frosting from being carried out even under performing a low outdoor temperature heating operation where an outdoor heat exchange is apt to be frosted and further to attain a superior air conditioning feeling. SOLUTION: An air condition in which a compressor 120 is driven by an engine 110 and a refrigerant pump bypass pipe passage 132 having a refrigerant pump 140 installed therein is mounted, comprises a first bypass pipe passage 150 connecting between branch points CD in parallel with the refrigerant pump 140 and the bypass opening and closing valve 141 and having a capillary tube 151 and a first opening and closing valve 152; a second opening and closing valve 143 arranged in a refrigerant pump bypass pipe passage 132 at a downstream side of a water heat exchanger 142; a second bypass pipe passage 160 connecting between branch pints EF and having a third opening and closing valve 161; and a fourth opening and closing valve 170 arranged at a high pressure liquid pipe 131 near an outdoor heat exchanger 124 from the branch point B.