To provide a heat pump device capable of accurately determining start of a defrosting operation without affected by change of a frequency of a compressor, variation of load, and the like.
This heat pump device includes an evaporator temperature detecting means for detecting a saturated temperature of a refrigerant in an evaporator, an evaporator sucked-air temperature detecting means for detecting a temperature of the air distributed to the evaporator, a refrigerant flow rate detecting means for detecting a flow rate of the refrigerant flowing in a refrigerant circuit, and a control section for determining whether the defrosting operation is started or not. The control section calculates an air volume of the air passing through the evaporator on the basis of an evaporation temperature detected by the evaporator temperature detecting means, an evaporator sucked-air temperature detected by the evaporator sucked-air temperature detecting means, and the refrigerant flow rate detected by the refrigerant flow rate detecting means, calculates a pressure loss and a wind velocity of the air passing through the evaporator on the basis of the air volume, and further calculates a thickness of the frost generated on the evaporator on the basis of the air volume and the wind velocity, to execute the defrosting operation when the thickness of a frost layer is a prescribed threshold value or more.
| JPH01134146A | 1989-05-26 | |||
| JP2007225158A | 2007-09-06 | |||
| JP2008224135A | 2008-09-25 | |||
| JP2008209017A | 2008-09-11 | |||
| JP2006183987A | 2006-07-13 | |||
| JPH02561U | 1990-01-05 |
Kiyoshi Yasushima
Takanashi Norio
Motoki Shandong
Taku Ogawa
Murata Kensei
Moto Otani
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