| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a compressor protecting controlling device for an air conditioner for keeping a stable heating operation state under an extremely-low outside air temperature. <P>SOLUTION: In this compressor protecting controlling device 20 comprising an outdoor piping temperature detecting means 6 detecting a refrigerant inlet-side piping temperature of an evaporator (not shown in the figure) in a heating operation, a compressor operational frequency control means 22 controlling an operational frequency of the compressor (not shown in the figure), and a piping temperature comparing detecting means 21 detecting and outputting that the piping temperature is lower than a first prescribed set temperature, when the piping temperature becomes lower than the first prescribed set temperature and higher than a second prescribed set temperature, and lowering the maximum compressor operational frequency when a boundary value lowering signal A is output by the piping temperature comparing detecting means 21, the first and second prescribed set temperatures are corrected according to the difference between a suction temperature and the piping temperature at the suction-side piping of the compressor, thus abnormal lowering of a suction pressure is prevented, and the stable heating operation state is kept. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
