JP2009250464A - Ventilation air conditioning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ventilation air conditioning device capable of performing a defrosting operation while continuing the heating of a bathroom 3 even during the defrosting operation, to solve a problem that a heating operation cannot be continued because of the frost formation of the moisture in the air on a surface of an evaporator 24 when the heating operation is continued for a long time in a state that the temperature of air supplied to the evaporator 24 is low in a ventilation air conditioning device used in the bathroom 3, a dressing room 4 and the like. <P>SOLUTION: A second suction opening 33 is formed at a ventilation air conditioner body 6, so that the frost on a surface of the evaporator 24 is melted by successively supplying air in the bathroom 3 sucked from the second suction opening 33 to the evaporator 24 and a condenser 20 in a defrosting operation. A suction opening 16 is provided with a first damper 29, and the first damper is closed in the defrosting operation, so that air in the bathroom 3 is sucked from the second suction opening 33. Furthermore, a defrosting damper 32 is disposed in a defrosting air trunk 31 communicating with the first air trunk 19 and the second air trunk 22, and is opened only at the defrosting operation to switch the flow channels in the defrosting operation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ventilation air conditioner that performs ventilation air conditioning in a bathroom or the like using a heat pump.

  As a ventilation air conditioner such as a bathroom using a conventional heat pump, the heat pump is separated into an outdoor unit and an indoor unit, and the heat exchanger provided in the outdoor unit absorbs heat (or radiates heat) from the outside air and is installed in the indoor unit. Some heat exchangers radiate (or absorb) heat in the bathroom air to air-condition the bathroom (see, for example, Patent Document 1).

  The ventilation air conditioner will be described below with reference to FIG.

A ventilation air conditioner exemplified in Patent Document 1 includes a condenser 102 and a circulation fan 103 that supplies air in the air conditioning target space to the condenser 102 in an indoor unit 101 installed in the air conditioning target space such as a bathroom. An evaporator 105 in an outdoor unit 104 installed outdoors, a blower fan 106 for supplying outdoor air to the evaporator 105, a compressor 107 for compressing refrigerant, and an expansion valve as a decompression mechanism for decompressing the refrigerant 108, and a refrigerant circuit 109 for sequentially connecting the compressor 107, the condenser 102, the expansion valve 108, and the evaporator 105 is provided. At the time of heating operation, the refrigerant compressed and heated by the compressor 107 is supplied to the condenser 102, and the air in the air-conditioning target space is supplied to the condenser 102 by the circulation blower 103. The air-conditioned room is heated by blowing into the space. At this time, the refrigerant cooled by the condenser 102 is further depressurized by the expansion valve 108 to be further lowered in temperature and sent to the evaporator 105. The evaporator 105 absorbs heat from the outdoor air supplied by the blower fan 106 to increase the temperature of the refrigerant, and the refrigerant returns to the compressor 107 again so that the heat of the outdoor air absorbed by the evaporator 105 is condensed into the condenser 102. Heat is dissipated in the air-conditioning target space for heating.
JP 2002-349930 A

  In such a conventional ventilation air conditioner, since the evaporator is installed outdoors and absorbs heat from the outdoor air, the temperature of the refrigerant circulating in the evaporator needs to be lower than the temperature of the outdoor air. However, when the temperature of outdoor air is low, such as in winter, especially in a situation where outdoor air is below 0 ° C, the temperature of the evaporator is also below 0 ° C, and the moisture contained in the outdoor air is evaporated. It is known that frost formation occurs due to freezing on the surface. In an evaporator in which frost formation has occurred, the air path of the outdoor air that flows through the evaporator is blocked by frost, making it difficult for air to pass through, so heat absorption in the evaporator cannot be performed and the refrigerant circuit becomes unstable. It is difficult to continue heating operation in a frosted state.

  For this reason, when a frost formation state generate | occur | produces, it is necessary to melt | dissolve the frost which generate | occur | produced on the evaporator surface by some means, and to recover | restore the distribution | circulation state of the outdoor air in an evaporator. The operation state for melting the frost generated on the surface of the evaporator is called defrosting operation or de-ice. As a general de-ice method, the operation of the refrigeration cycle is stopped and only the air is sent to the evaporator. There is a method of dissolving the frozen water using the temperature of the air. In this case, the temperature of air needs to be higher than the temperature at which water freezes (generally 0 ° C.). Therefore, there is a method of performing deice by operating the refrigeration cycle, reducing the pressure reduction amount in the expansion mechanism upstream of the evaporator, increasing the refrigerant inflow temperature to the evaporator, and increasing the evaporator temperature. . In this case, although the temperature of the evaporator rises, the evaporator originally absorbs heat from the air passing through the evaporator, whereas the amount of heat supply decreases or decreases as the temperature of the evaporator rises. Depending on the temperature of the air, the heat is dissipated. For this reason, there has been a problem that heating cannot be performed on the air-conditioning target space during the de-ice operation. Another method is to reverse the refrigerant flow direction in the refrigeration cycle and temporarily melt the frozen water by allowing the evaporator to act as a condenser, but by reversing the evaporator and condenser. Therefore, the air-conditioning target space to be heated is originally cooled, and there is a problem that the user feels cold air or the temperature of the air-conditioning target space is lowered.

  This invention solves the said conventional subject, and it aims at providing the ventilation air conditioner which can perform a defrost, without stopping the heating of air-conditioning object space at the time of a defrost operation.

  Moreover, it aims at providing the ventilation air conditioner which can shorten the period concerning defrost operation, and can restart heating operation earlier.

  It is another object of the present invention to provide a ventilation air conditioner that can reduce the running cost during the defrosting operation and can heat the air-conditioned room more efficiently.

  In order to achieve the above object, the first solution taken by the present invention includes a compressor, a condenser, a pressure reducing mechanism, an evaporator, and a condenser fan for blowing air from the air-conditioned room to the condenser. In an air conditioner that heats an air-conditioning target room by a refrigeration cycle using an evaporator fan for blowing heat absorption target air to the evaporator, the air in the air-conditioning target room during the defrosting operation of the evaporator is in the order of evaporator and condenser. The evaporator is defrosted while heating the air-conditioning target room by ventilating.

  This means that during the defrosting operation, the amount of heat input to the compressor can be added to the heat of the air in the air-conditioning target room and supplied to the air-conditioning target room. Since the frost operation can be performed, the defrost operation can be performed without stopping the heat input to the air-conditioning target room that has been stopped during the conventional defrost operation.

  In addition, the second solving means taken by the present invention includes a circulation fan that sucks air from a suction port that opens into a first indoor space that is an air-conditioning target space and blows out air from a blowout port that opens into the first indoor space. , A ventilation fan that ventilates by sucking air from an exhaust port opened in the second indoor space other than the first indoor space and discharging it to the outdoors, a compressor that compresses the refrigerant, and air blown by the circulation fan In a ventilation air conditioner provided with a refrigerant circuit in which the refrigerant circulates in the order of a condenser for exchanging heat with the refrigerant, a decompression mechanism for depressurizing the refrigerant, and an air blown by the ventilation fan and an evaporator for exchanging heat between the refrigerant, A defrosting air passage communicating between the evaporator and the condenser and a defrosting air passage closing means for closing air flow in the defrosting air passage are further provided, and during the defrosting operation of the evaporator Air in the air-conditioned room The through defrosting air duct evaporator, in which so as to implement the defrosting of the evaporator while performing the heating of the first indoor space by blowing air in the order of the condenser.

  This means that during the defrosting operation, the heat input to the compressor can be added to the heat of the air in the first indoor space and supplied to the first indoor space, so heat input to the first indoor space is stopped. It is possible to perform the defrosting operation without performing the defrosting operation without stopping the heat input to the first indoor space that has been stopped during the conventional defrosting operation, It is possible to separate / integrate the respective ventilation paths required during the heating operation or the defrosting operation, and to switch between the heating operation and the defrosting operation without providing a dedicated air passage.

  The third solution provided by the present invention is to close the defrost air passage closing means during the heating operation and open the defrost air passage closing means during the defrost operation.

  By this means, during the heating operation, the air flow from the evaporator to the condenser is stopped, and the heating capacity is reduced in order to prevent the air from flowing into the condenser from the second indoor space through the evaporator. It is possible to perform the heating operation without any trouble, and at the time of the defrosting operation, the air flow from the evaporator to the condenser is opened, and the defrosting is performed by passing the defrosting air passage to the first indoor space. Heat input can be performed.

  The fourth solution provided by the present invention further includes a second suction port for sucking air to be conditioned in the first indoor space, and the air to be conditioned from the second suction port during the defrosting operation. The air-conditioning target air is supplied to the condenser by suction.

  This means simplifies the air path through which the air-conditioning target air flows during the defrosting operation, allowing ventilation with less pressure loss, and uniform supply of the air-conditioning target air to the evaporator during the defrosting operation. The defrosting operation time can be shortened.

  The fifth solution provided by the present invention is provided with a first closing mechanism and a second closing mechanism for closing the suction ports at the suction port and the second suction port, respectively.

  By this means, it becomes possible to suck the air-conditioning target air in the first indoor space only from the suction port required at the time of heating operation or defrosting operation. The defrosting operation time at the time can be shortened.

  The sixth solution provided by the present invention is that the second closing mechanism is closed during the heating operation and the air-conditioning target air is sucked from the intake port, and the first closing mechanism is closed during the defrosting operation and the second intake mechanism is closed. Air to be air-conditioned is sucked from the mouth.

  By this means, it becomes possible to suck the air-conditioning target air in the first indoor space from the suction port and supply it to the condenser during the heating operation, and to prevent the air-conditioning target air from flowing into the evaporator from the second suction port. It becomes possible to stop, and it becomes possible to prevent the fall of the heating capability at the time of heating operation. In addition, during the defrosting operation, air to be air-conditioned in the first indoor space can be sucked from the second suction port and vented in the order of the evaporator and the condenser, and the inflow of air-conditioning target air from the suction port is stopped. By doing so, it is possible to prevent the temperature of the refrigerant in the refrigerant circuit from being lowered, and to shorten the defrosting operation time.

  Further, the seventh solving means taken by the present invention is to stop the ventilation from the second indoor space during the defrosting operation.

  This means improves the heating effect on the first indoor space by preventing the air in the second indoor space from flowing into the first indoor space via the evaporator during the defrosting operation. Even when the air in the space is contaminated with dust or odor, the inflow of dust or odor into the first indoor space can be prevented.

  Further, an eighth solution provided by the present invention is to close the supply of air from the second indoor space in the exhaust air passage that supplies the air in the second indoor space sucked from the exhaust port to the evaporator. A third closing mechanism is provided.

  By this means, air can be prevented from flowing into the ventilation air conditioner from the second indoor space, the heating effect to the first indoor space can be improved, and dust in the second indoor space to the first indoor space can be prevented. Odor inflow can be prevented.

  The ninth solution provided by the present invention is such that the third closing mechanism is opened during the heating operation, and the third closing mechanism is closed during the defrosting operation.

  By this means, during the heating operation, the air in the second indoor space is supplied from the second indoor space to the evaporator, so that the heat absorbed from the air in the second indoor space is cooled by the condenser in the first indoor space. While heating by supplying to the air, it prevents the air in the second indoor space from flowing into the evaporator from the second indoor space during the defrosting operation, and dust and odor in the second indoor space Inflow into the space can be prevented.

  The tenth solution taken by the present invention is that the air in the first indoor space is sucked by the circulation fan during the defrosting operation, and the evaporator and the condenser are ventilated in this order.

  By this means, it becomes possible to perform circulating air blowing without providing a separate fan for circulating the air in the bathroom into the main body during the defrosting operation.

  The eleventh solution provided by the present invention is that the ventilation fan and the circulation fan are operated during the defrosting operation, and a part of the air-conditioning target air sucked from the first indoor space is passed in the order of the evaporator and the condenser. Circulating air to the first indoor space and exhausting part of the air-conditioned air sucked from the first indoor space to the outside through the evaporator increases the heat absorption amount in the evaporator and raises the temperature of the evaporator. It is what I did.

  By this means, the heat absorption amount in the evaporator is increased, the temperature of the evaporator circuit is increased by increasing the temperature of the entire refrigerant circuit, the frost generated in the evaporator is easily melted, and the defrosting operation time is shortened. It becomes possible.

  A twelfth solution provided by the present invention is that a refrigerant heating means for heating the refrigerant is provided on the refrigerant circuit between the decompression mechanism and the evaporator, and the refrigerant is heated by the refrigerant heating means during the defrosting operation. Thus, the defrosting time is shortened and the first indoor space is heated.

  By this means, the temperature of the refrigerant in the refrigerant circuit is increased by supplying heat from the heating means to the refrigerant circuit during the defrosting operation, so that the frost generated in the evaporator is easily melted and the defrosting operation time is shortened. Is possible.

  The thirteenth solution provided by the present invention comprises a heater that is heated by energization of the refrigerant heating means.

  By this means, it is possible to heat the refrigerant circuit relatively easily, and the defrosting operation time can be shortened without increasing the size of the ventilation air conditioner body.

  The fourteenth solution taken by the present invention is a hot water heat exchanger that heats an object by passing hot water through the refrigerant heating means.

  By this means, it is possible to supply a relatively large amount of heat to the refrigerant circuit without causing problems such as ignition, so that the defrosting operation time can be shortened.

  The fifteenth solution taken by the present invention is to automatically switch the flow path of the air in the first indoor space when the evaporator is frosted.

  By this means, the user can automatically start the defrosting operation without performing a special operation at the time of frosting, and the convenience for the user can be improved.

  According to a sixteenth solution provided by the present invention, an evaporator temperature detecting means for detecting the temperature of the evaporator is provided to detect frost formation on the evaporator according to the temperature of the evaporator. .

  By this means, it is possible to accurately determine the frost formation of the evaporator, and to promptly shift to the defrosting operation at the time of frost formation, thereby improving the convenience for the user.

  The seventeenth solution taken by the present invention is to automatically switch the flow path of the air in the first indoor space to the ventilation path during normal heating operation when the defrosting of the evaporator is completed.

  By this means, it becomes possible to automatically restart the heating operation without any special operation by the user at the end of the defrosting operation, and the convenience for the user can be improved.

  The eighteenth solution taken by the present invention is to detect the temperature of the air in the first indoor space and reduce the amount of pressure reduction by the pressure reducing mechanism when the temperature of the air in the first indoor space is low. It is a thing.

  By this means, when the temperature of the air in the first indoor space is low, the defrosting time may be prolonged only by supplying the air in the first indoor space to the evaporator. By reducing the amount, it is possible to increase the temperature of the refrigerant supplied to the evaporator and melt frost generated in the evaporator at an early stage.

  According to a nineteenth solution taken by the present invention, the amount of pressure reduction by the pressure reduction mechanism is increased when the temperature of the air in the first indoor space exceeds a predetermined temperature.

  By this means, if the temperature of the air in the first indoor space exceeds a predetermined temperature during the defrosting operation, the amount of heat absorbed in the evaporator rises. Since a temperature sufficient for melting the frost generated on the evaporator surface can be obtained, the heating capacity for the first indoor space can be improved by increasing the amount of decompression.

  The twenty-first solution provided by the present invention is to detect the temperature of the air in the first indoor space and increase the amount of air blown by the circulation fan when the temperature of the air in the first indoor space is low. It is what I did.

  By this means, the amount of air to be air-conditioned passing through the evaporator is increased to increase the amount of heat absorbed by the evaporator, the temperature of the refrigerant in the refrigerant circuit is increased, and the frost generated in the evaporator at an early stage is increased. It can be melted.

  According to a twenty-first solution provided by the present invention, the amount of air blown by the circulation fan is reduced when the temperature of the air in the first indoor space exceeds a predetermined temperature.

  By this means, when the temperature of the air in the first indoor space exceeds a predetermined temperature during the defrosting operation, the amount of heat absorbed in the evaporator increases, so the amount of air blown by the circulation fan is reduced. Since the temperature in the evaporator is sufficient to melt the frost generated on the surface of the evaporator, the amount of air blown by the circulation fan is reduced, the temperature of the air blown into the first indoor space is increased, The feeling of cold wind that occurs when a person is present in one indoor space can be reduced.

  According to a twenty-second solution provided by the present invention, the temperature detection means in the first indoor space is provided in the air flow path in the vicinity of the second suction port.

  By this means, it is possible to accurately detect the temperature of the air in the first indoor space during the defrosting operation, and it is possible to accurately control the operation status of the ventilation air conditioner during the defrosting operation.

  According to the present invention, it is possible to perform the defrosting operation while continuing the heating of the air-conditioning target room even when the evaporator is in a frosting state during the heating operation at a low temperature. Thus, it is possible to improve the convenience of the user.

  Further, the defrosting operation period can be shortened, and the convenience for the user can be improved.

  Moreover, the energy consumption at the time of a defrost operation can be reduced and the ventilation air conditioner of low running cost can be provided.

  In addition, it is possible to provide a ventilation air conditioner that does not require user operation related to the defrosting operation and can perform efficient heating without impairing user convenience.

  According to the first aspect of the present invention, a compressor, a condenser, a decompression mechanism, an evaporator, a condenser fan that blows air from an air-conditioning target room to the condenser, and an endothermic air to the evaporator are blown. In an air conditioner that heats an air-conditioned room by a refrigeration cycle using an evaporator fan, the air in the air-conditioned room is passed through the evaporator and the condenser in that order during the defrosting operation of the evaporator to The evaporator is defrosted while heating is performed. During the defrosting operation, the amount of heat input to the compressor is added to the heat of the air in the air-conditioned room and supplied to the air-conditioned room. Therefore, the defrosting operation can be performed without stopping the heat input to the air-conditioning target room. Therefore, the heat input to the air-conditioning target room that has been stopped during the conventional defrosting operation can be performed without stopping. It becomes possible to perform frost operation .

  A circulation fan that sucks air from a suction port opened in the first indoor space, which is an air-conditioning target space, and blows out air from a blowout port opened in the first indoor space; and a second indoor space other than the first indoor space A ventilation fan that ventilates by sucking air from the opened exhaust port and discharging it outdoors, a compressor that compresses the refrigerant, a condenser that exchanges heat between the air blown by the circulation fan and the refrigerant, and decompression of the refrigerant In the ventilation air conditioner provided with a refrigerant circuit in which the refrigerant circulates in the order of the pressure reducing mechanism for performing the cooling and the air blown by the ventilation fan and the evaporator for exchanging heat with the refrigerant, the evaporator and the condenser are connected to each other A defrost air passage closing means for closing air flow in the frost air passage and the defrost air passage is further provided, and air in the air-conditioning target room is passed through the defrost air passage during the defrost operation of the evaporator. Evaporator, condenser The defrosting of the evaporator is performed while heating the first indoor space by blowing air, and the heat of the air in the first indoor space is transferred to the compressor during the defrosting operation. Since the amount of input heat can be added and supplied to the first indoor space, it is possible to perform the defrosting operation without stopping the heat input to the first indoor space. In addition, the defrosting operation can be performed without stopping the heat input to the first indoor space, and the respective ventilation paths required during the heating operation or the defrosting operation can be separated / integrated. The heating operation and the defrosting operation can be switched without providing a dedicated air passage.

  In addition, the defrosting air passage closing means is closed during the heating operation, and the defrosting air passage closing means is opened during the defrosting operation. By this means, the air from the evaporator to the condenser is used during the heating operation. In order to prevent the air from flowing into the condenser from the second indoor space through the evaporator, it is possible to perform the heating operation without deteriorating the heating capacity and to perform the defrosting operation. Occasionally, the flow of air from the evaporator to the condenser is released, and the defrost air passage is ventilated, so that heat can be input into the first indoor space while defrosting.

  Further, a second suction port for sucking air to be conditioned in the first indoor space is further provided, and air to be conditioned is sucked into the condenser by sucking air to be conditioned from the second suction port during the defrosting operation. It is designed to supply air, simplifies the air path through which air to be conditioned flows during defrosting operation, and allows ventilation with less pressure loss, and evaporates during defrosting operation. The air-conditioning target air can be uniformly supplied to the vessel, and the defrosting operation time can be shortened.

  Also, the suction port and the second suction port are provided with a first closing mechanism and a second closing mechanism for closing the respective suction ports, which are required during heating operation or defrosting operation, respectively. It becomes possible to suck the air-conditioning target air in the first indoor space from only the suction port, and it is possible to prevent the heating capacity from being lowered during the heating operation and to shorten the defrosting operation time during the defrosting operation.

  Also, during the heating operation, the second closing mechanism is closed and the air-conditioning target air is sucked from the intake port, and during the defrosting operation, the first closing mechanism is closed and the air-conditioning target air is sucked from the second intake port. During heating operation, the air to be conditioned in the first indoor space can be sucked from the suction port and supplied to the condenser, and the air to be conditioned from the second suction port can flow into the evaporator. It becomes possible to stop, and it becomes possible to prevent the fall of the heating capability at the time of heating operation. In addition, during the defrosting operation, air to be air-conditioned in the first indoor space can be sucked from the second suction port and vented in the order of the evaporator and the condenser, and the inflow of air-conditioning target air from the suction port is stopped. By doing so, it is possible to prevent the temperature of the refrigerant in the refrigerant circuit from being lowered, and to shorten the defrosting operation time.

  In addition, ventilation from the second indoor space is stopped during the defrosting operation, and air in the second indoor space is prevented from flowing into the first indoor space via the evaporator during the defrosting operation. To improve the heating effect to the first indoor space and prevent the inflow of dust and odor into the first indoor space even when the air in the second indoor space is contaminated with dust and odor Can do.

  Further, a third closing mechanism for closing the supply of air from the second indoor space is provided in the exhaust air passage for supplying air in the second indoor space sucked from the exhaust port to the evaporator. The air can be prevented from flowing into the ventilation air conditioner from the second indoor space, the heating effect to the first indoor space is improved, and the inflow of dust and odor in the second indoor space to the first indoor space Can be prevented.

  Further, the third closing mechanism is opened during the heating operation, and the third closing mechanism is closed during the defrosting operation. During the heating operation, the evaporator is moved from the second indoor space to the evaporator. Heat is supplied by supplying air from the air in the second indoor space by supplying air to the air-conditioning target air in the first indoor space by the condenser, and at the time of defrosting operation, the evaporator is discharged from the second indoor space. It is possible to prevent the air in the second indoor space from flowing in, and to prevent the dust and odor in the second indoor space from flowing into the first indoor space.

  Also, the air in the first indoor space is sucked by the circulation fan during the defrosting operation, and the evaporator and the condenser are ventilated in this order. By this means, the air in the bathroom is removed from the main body during the defrosting operation. It is possible to perform circulating air blowing without separately providing a fan for circulation inside.

  Further, during the defrosting operation, the ventilation fan and the circulation fan are operated, and a part of the air-conditioning target air sucked from the first indoor space is ventilated in the order of the evaporator and the condenser, and is circulated and blown to the first indoor space. A part of air to be air-conditioned sucked from the space is exhausted to the outside through the evaporator, so that the heat absorption amount in the evaporator is increased and the temperature of the evaporator is raised. The heat absorption amount in the evaporator By increasing the temperature of the entire refrigerant circuit, the temperature of the evaporator surface is increased, the frost generated in the evaporator can be easily melted, and the defrosting operation time can be shortened.

  In addition, a refrigerant heating means for heating the refrigerant is provided on the refrigerant circuit between the decompression mechanism and the evaporator, and the defrosting time is shortened by heating the refrigerant by the refrigerant heating means during the defrosting operation and the first chamber. It is intended to heat the space, by raising the temperature of the refrigerant in the refrigerant circuit by putting heat by the heating means into the refrigerant circuit during the defrosting operation, making it easier to melt the frost generated in the evaporator, It is possible to shorten the defrosting operation time.

  In addition, the refrigerant heating means is composed of a heater that heats by energization, and heat can be input to the refrigerant circuit relatively easily, and the defrosting operation time can be obtained without increasing the size of the ventilation air conditioner body. Can be shortened.

  The refrigerant heating means is composed of a hot water heat exchanger that heats the target by passing hot water, and supplies a relatively large amount of heat to the refrigerant circuit without causing problems such as ignition. Therefore, the defrosting operation time can be shortened.

  In addition, when the evaporator is frosting, the flow path of the air in the first indoor space is automatically switched, and the defrosting operation is automatically started without any special operation by the user during frosting. And user convenience can be improved.

  Further, an evaporator temperature detecting means for detecting the temperature of the evaporator is provided, and the frost formation of the evaporator is detected according to the temperature of the evaporator, and the frost formation of the evaporator is accurately determined, It becomes possible to promptly shift to the defrosting operation at the time of frost formation, and the convenience for the user can be improved.

  In addition, when the defrosting of the evaporator is completed, the flow path of the air in the first indoor space is automatically switched to the ventilation path during the normal heating operation, and the user performs a special operation at the end of the defrosting operation. It becomes possible to automatically restart the heating operation without performing it, and the convenience for the user can be improved.

  Further, the temperature of the air in the first indoor space is detected, and when the temperature of the air in the first indoor space is low, the amount of pressure reduction by the pressure reducing mechanism is reduced. If the temperature of the air is low, simply supplying the air in the first indoor space to the evaporator may result in a longer defrosting time. It is possible to increase the temperature of the supplied refrigerant and melt frost generated in the evaporator at an early stage.

  Further, when the temperature of the air in the first indoor space exceeds a predetermined temperature, the amount of pressure reduction by the pressure reducing mechanism is increased, and the temperature of the air in the first indoor space is predetermined during the defrosting operation. Since the endothermic amount in the evaporator rises when the temperature exceeds the temperature of the evaporator, the temperature in the evaporator is sufficient to melt the frost generated on the surface of the evaporator even if the amount of decompression by the decompression mechanism is increased. Therefore, the heating capacity for the first indoor space can be improved by increasing the amount of decompression.

  Further, the temperature of the air in the first indoor space is detected, and when the temperature of the air in the first indoor space is low, the amount of air blown by the circulation fan is increased and passes through the evaporator. By increasing the amount of air to be air-conditioned, the amount of heat absorbed by the evaporator is increased, the temperature of the refrigerant in the refrigerant circuit is increased, and frost generated in the evaporator at an early stage can be melted.

  Further, when the temperature of the air in the first indoor space exceeds a predetermined temperature, the amount of air blown by the circulation fan is reduced, and the temperature of the air in the first indoor space during the defrosting operation. When the temperature exceeds a predetermined temperature, the amount of heat absorbed by the evaporator rises. Therefore, even if the amount of air blown by the circulation fan is reduced, the temperature at the evaporator melts the frost generated on the evaporator surface. Since sufficient temperature can be obtained, the amount of air blown by the circulation fan can be reduced, the temperature of the air blown into the first indoor space can be increased, and the feeling of cold air generated when there are people in the first indoor space can be reduced. it can.

  Further, the temperature detecting means in the first indoor space is provided in the air flow path near the second suction port, and the temperature of the air in the first indoor space during the defrosting operation is accurately detected. Therefore, it is possible to accurately control the operation status of the ventilation air conditioner during the defrosting operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a sketch of a living space in which a ventilation air conditioner according to an embodiment of the present invention is installed. In FIG. 1, an indoor living space 1 is partitioned into a living room 2 as an indoor space, a bathroom 3 as a first indoor space, a dressing room 4 as a second indoor space, or a toilet 5. The main body 6 of the ventilation air conditioner is installed on the back. The main body 6 includes a first exhaust duct 7 communicating with the main body 6 and the outdoors, a second exhaust duct 9 communicating with the main body 6 and a first exhaust port 8 serving as an exhaust opening opened in the ceiling of the dressing room 4, and a toilet 5. The 3rd exhaust duct 11 which connects the 2nd exhaust port 10 and the main body 6 which were opened to the ceiling of this is connected.

  In addition, a ventilation fan 12 is disposed inside the main body 6, and a first exhaust duct 7 that communicates between the outdoor body and the main body 6 is connected to a blow-out side of the ventilation fan 12, and a undressing chamber 4 and the main body 6 communicate with each other. The second exhaust duct 9 and the third exhaust duct 11 communicating the toilet 5 and the main body 6 are connected to the suction side of the ventilation fan 12. Therefore, when the ventilation fan 12 is operated, the air in the dressing room 4 and the toilet 5 is sucked into the ventilation fan 12 from the first exhaust port 8 and the second exhaust port 10 through the second exhaust duct 9 and the third exhaust duct 11. The air is exhausted outdoors through one exhaust duct 7.

  When the ventilation fan 12 is continuously operated, the inside of the indoor living space 1 becomes negative pressure, so that fresh outside air is supplied from the air supply opening 13 opened on the wall facing the outside of the living room 2 as the indoor space. The living space 1 will be ventilated. Since this ventilation operation needs to be performed continuously when the confidentiality of the building is high (24-hour ventilation), the ventilation fan 12 corresponds to a predetermined ventilation amount, for example, about half the volume of the living space 1 in one hour. Operate continuously to ensure ventilation.

  The living room 2 is provided with an air conditioner 14 for controlling the temperature of the room. The air conditioner 14 is used for cooling in the summer and heating in the winter to keep the room temperature properly. Therefore, when continuous ventilation operation is performed throughout the year as described above, in the living room, the air conditioner 14 is used for cooling in the summer, and the air conditioner 14 is used for heating in the winter. The air controlled at 0 ° C. is sucked into the first exhaust port 8 and the second exhaust port 10 through the louver and undercut portions of the door 15 of the dressing room 4 and the toilet 15 and passes through the main body 6 of the ventilation air conditioner. It will be discharged outdoors.

  2 and 3 are an air passage configuration diagram and a refrigerant circuit diagram of the ventilation air conditioner. As shown in FIGS. 1 and 2, a main body 6 of the ventilation air conditioner is installed behind the ceiling of the bathroom 3. A suction port 16 and an air outlet 17 are opened at the bottom of the bathroom 6 with respect to the ceiling surface of the bathroom 3, and a filter 18 is provided in the suction port 16 for detachably capturing dust.

  In the first air passage 19 in the main body 6, a suction port 16 for sucking air in the bathroom 3, a condenser 20 for raising the temperature of the air in the bathroom 3 sucked from the suction port 16, and the condenser 20 are raised. A circulation fan for sucking the air in the bathroom 3 from the air outlet 17 and the inlet 16 for blowing the heated air into the bathroom 3 and circulating the air from the air outlet 17 through the condenser 20 into the bathroom 3 again. 21 is provided, and the inside of the bathroom 3 can be heated by circulating air in the order of the suction port 16, the condenser 20, the circulation fan 21, and the blowout port 17 as indicated by the arrows.

  Further, in the second air passage 22 in the main body 6, the first exhaust duct 7 is connected to the main body 6 in the dressing room 4 and the toilet 5 sucked from the first exhaust port 8 and the second exhaust port 10. A first ventilation port 23 for ventilating air into the main body 6, an evaporator 24 for absorbing heat from the air in the dressing room 4 and the toilet 5 sucked from the first ventilation port 23, and air absorbed by the evaporator 24 For sucking the air in the dressing room 4 and the toilet 5 from the ventilation outlet 25 and the first ventilation outlet 23 for discharging the air to the third exhaust duct 11 and exhausting the air from the ventilation outlet 25 through the evaporator 24 to the outside. The ventilation fan 12 is provided, and the flow of wind is blown in the order of the first ventilation port 23, the evaporator 24, the ventilation fan 12, and the ventilation outlet 25, as indicated by the arrows, so After absorbing heat from the air of the It can be ventilated in the space 1.

  In addition, for example, an HCFC refrigerant (including chlorine, hydrogen, fluorine, and carbon atoms in the molecule) and an HFC refrigerant (including hydrogen, carbon, and fluorine atoms in the molecule) as the refrigerant in the main body 6. A refrigerant circuit 26 filled with any of natural refrigerants such as hydrocarbons and carbon dioxide is formed. In this refrigerant circuit 26, a compressor 27 for compressing the refrigerant, heat exchange between the supply air and the refrigerant A condenser 20 to be expanded, an expansion valve 28 as a pressure reducing mechanism for reducing the pressure by expanding the refrigerant, and an evaporator 24 for exchanging heat between the supply air and the refrigerant.

  The suction port 16 is provided with a first damper 29 as a first closing mechanism for closing the intake air from the bathroom 3, and the suction of air from the bathroom 3 is stopped by closing the first damper 29. can do. Further, the first ventilation port 23 is provided with a second damper 30 as a third closing mechanism for closing the suction of air from the dressing room 4 and the toilet 5, and the second damper 30 is closed. Thus, the suction of air from the dressing room 4 and the toilet 5 can be stopped. Further, a defrost air passage communicating the second air passage 22 and the first air passage 19 in a portion adjacent to the first air passage 19 downstream of the evaporator 24 and upstream of the ventilation fan 12 in the second air passage 22. 31 is provided, and a defrost damper 32 is provided in the defrost air passage 31 as defrost air passage closing means for closing communication between the second air passage 22 and the first air passage 19. .

  The defrost air passage 31 communicates with a position downstream of the suction port 16 of the first air passage 19 and upstream of the condenser 20, and after passing through the evaporator 24 in the second air passage 22 when the defrost damper 32 is opened. Is ventilated to the condenser 20 in the first air passage 19 through the defrost air passage 31. When the defrost damper 32 is closed, the first air passage 19 and the second air passage 22 are isolated from each other, and the air flowing through each air passage is ventilated without being mixed. A second suction port for introducing the air in the bathroom 3 into the second air passage 22 at a position downstream of the first ventilation port 23 in the second air passage 22 and upstream of the evaporator 24. The second suction port 33 is provided, and the second suction port 33 is provided with a third damper 34 as a second closing mechanism for closing the second suction port 33. It is possible to switch to the optimum air path for each operation mode by appropriately opening and closing each damper described above according to each operation mode.

  Next, the operation of the ventilation air conditioner will be described. Table 1 is a list showing the operating state of each component in each operation pattern. Hereinafter, each operation mode will be described in detail.

  First, in the heating operation mode, the first damper 29 and the second damper 30 are opened, and the third damper 34 and the defrost damper 32 are closed. In this case, the air in the bathroom 3 sucked from the suction port 16 is heated by the condenser 20 and then circulated to the bathroom 3 by the circulation fan 21 to heat the bathroom 3. The air in the dressing room 4 and the toilet 5 sucked from the first ventilation port 23 is exhausted to the outdoors by the ventilation fan 12 while the heat is absorbed by the evaporator 24 and the temperature is lowered. Since the heat absorbed from the air in the dressing room 4 and the toilet 5 by the evaporator 24 is supplied into the bathroom 3 by the condenser 20, the heat conditioned by the air conditioner 14 or the like in the living space 1 is ventilated outdoors. It is possible to efficiently perform heating by collecting in the bathroom 3 without wastefully discharging.

  Next, in the bathroom ventilation operation mode, the third damper 34 is opened, and the first damper 29, the second damper 30, and the defrost damper 32 are closed. In this case, only the ventilation fan 12 is operated, and the operation of the circulation fan 21 is stopped. The air in the bathroom 3 sucked from the second suction port 33 by the ventilation fan 12 is exhausted to the outdoors from the ventilation outlet 25 by the ventilation fan 12. At this time, since the operation of the compressor 27 is not performed and the heat absorption in the evaporator 24 is not performed, the air in the bathroom 3 is exhausted to the outside as it is.

  Next, in the other room ventilation mode, the second damper 30 is opened, and the first damper 29, the third damper 34, and the defrost damper 32 are closed. In this case, only the ventilation fan 12 is operated, and the operation of the circulation fan 21 is stopped. The air in the dressing room 4 and the toilet 5 sucked from the first ventilation port 23 by the ventilation fan 12 is exhausted from the ventilation outlet 25 to the outside by the ventilation fan 12. At this time, since the operation of the compressor 27 is not performed and the heat absorption in the evaporator 24 is not performed, the air in the dressing room 4 and the toilet 5 is exhausted to the outside as it is.

  Next, the defrosting operation mode will be described in detail. In the defrosting operation mode, when the temperature of the air in the dressing room 4 and the toilet 5 is low during the heating operation, or when it is desired to increase the heating effect on the bathroom 3, the refrigerant is evaporated by increasing the amount of refrigerant reduced in the expansion valve 28. When the temperature of the evaporator is lowered, moisture in the air freezes on the surface of the evaporator 24 (frosting state), the surface of the evaporator 24 is covered with frost, and the heat exchange capacity of the evaporator 24 is reduced. In addition, this is an operation mode for melting the frost generated on the surface of the evaporator 24 and restoring the heat exchange capability of the evaporator 24.

  When the heating operation is continued in the frosting state, the temperature of the refrigerant in the refrigerant circuit continues to gradually decrease, and if the temperature falls below the operating range of the compressor 27, the operation becomes impossible. It is common to restart the heating operation after melting the frost on the surface of the evaporator 24 by performing the defrosting operation when the frosting occurs. The defrosting operation mode is an operation mode for eliminating such a frosting state, and the heat exchange capability of the evaporator 24 is restored by melting the frost on the surface of the evaporator 24 by performing the defrosting operation mode. It is an operation mode for making it happen.

  In an ordinary refrigerant circuit-equipped device, a method is employed in which the operation of the compressor 27 is stopped during the defrosting operation and the frost is melted by the heat of the air supplied by blowing air to the evaporator 24. However, in the case of such a defrosting system, when the temperature of the supplied air is not higher than the temperature at which water is frozen, that is, generally 0 ° C. or lower, the frost generated on the surface of the evaporator 24 is not melted. Depending on the environment, it will continue to grow, so defrosting is not possible in all environmental conditions. For this reason, the supply of air to the evaporator 24 and the condenser 20 is stopped, only the compressor 27 is operated, the temperature of the refrigerant in the refrigerant circuit 26 is increased, and the high-temperature refrigerant is circulated to the evaporator 24. In some cases, a method of melting frost on the surface of the evaporator 24 may be taken. However, as in the case where only the air blowing described above is performed, since the heat input to the bathroom 3 that is the air-conditioning target space is stopped, it is necessary to temporarily stop the heating in the bathroom 3. In the present invention, even in the defrosting operation mode, the defrosting operation can be performed without stopping the supply of heat to the bathroom 3 that is the air-conditioning target space.

  In the defrosting operation mode, the defrosting damper 32 and the third damper 34 are opened, and the first damper 29 and the second damper 30 are closed. In this case, only the circulation fan 21 is operated, and the operation of the ventilation fan 12 is stopped. Detection of the frosting state of the evaporator 24 is performed based on a value obtained by an evaporator temperature sensor 35 as an evaporator temperature detecting means provided in the evaporator 24. When the temperature of the evaporator 24 detected by the evaporator temperature sensor 35 during the heating operation falls below a certain value (for example, 0 ° C.) for a certain period (for example, 10 minutes) or more, frost is generated on the surface of the evaporator 24. Detect and automatically shift to defrosting operation mode.

  When transitioning to the defrosting operation mode, the air in the bathroom 3 is supplied from the second suction port 33 to the evaporator 24 by the circulation fan 21. Since the air in the bathroom 3 has been heated by the heating operation that has been performed until the mode shifts to the defrosting operation mode, relatively high-temperature air is supplied to the evaporator 24. The air sucked from the inside of the bathroom 3 through the second suction port 33 melts the frost on the surface of the evaporator 24 when passing through the evaporator 24 and is absorbed by the evaporator 24 to reduce the temperature. 20 is supplied. In the condenser 20, the heat absorbed by the evaporator 24 and the electric power consumed to drive the compressor 27 are given to the air as heat, so that the temperature of the air that has passed through the condenser 20 is from the second suction port 33. The temperature rises from the temperature at the time of suction, and the air is circulated from the air outlet 17 to the bathroom 3. For this reason, it becomes possible to perform the defrost operation which melts the frost which generate | occur | produced on the surface of the evaporator 24, without stopping the heating with respect to the bathroom 3. FIG.

  During the defrosting operation, by supplying air in the bathroom 3 having a relatively high temperature to the evaporator 24, the amount of heat absorbed by the evaporator 24 is increased as compared with that during the heating operation. Therefore, the temperature of the refrigerant in the refrigerant circuit 26 is increased. Is slightly higher than during heating operation. For this reason, the effect | action which melts the frost in the evaporator 24 surface also becomes large, and the time concerning defrosting can also be shortened. Further, the amount of air blown by the circulation fan 21 during the defrosting operation, the expansion valve by detecting the temperature in the bathroom 3 by the suction temperature sensor 36 as a temperature detecting means provided near the second suction port 33 during the defrosting operation. Optimize the reduced pressure of 28.

  When the temperature in the bathroom 3 is low, the amount of heat absorbed in the evaporator 24 is increased, so that the amount of air blown by the circulation fan 21 is increased and the amount of pressure reduced by the expansion valve 28 is decreased, and the refrigerant supplied to the evaporator 24 The temperature of the is increased and the time required for the defrosting operation is shortened. When the temperature of the air in the bathroom 3 is even lower, the third damper 34 is opened and the ventilation fan 12 is operated to exhaust the air in the bathroom 3 to the outside through the evaporator 24 and circulate the fan 21. Thus, the air in the bathroom 3 is circulated and blown into the bathroom 3 through the evaporator 24 and the condenser 20 to perform the defrosting operation. By doing in this way, since the heat absorption amount in the evaporator 24 can be increased with respect to the heat radiation amount in the condenser 20, the temperature of the refrigerant in the refrigerant circuit 26 is raised, and the air in the bathroom 3 is increased. Even when the temperature is low, the defrosting operation can be completed in a short time.

  At the end of the defrosting operation, the defrosting damper 32 and the third damper 34 are automatically closed, the first damper 29 and the second damper 30 are automatically opened to change the air path configuration, and the heating operation is automatically performed. To come back.

  Further, as shown in FIG. 2, a heater 37 as a refrigerant heating means for heating the refrigerant in the refrigerant circuit 26 is provided between the expansion valve 28 and the evaporator 24 on the refrigerant circuit 26. When the temperature in the bathroom 3 is low, or when it is necessary to finish the defrosting operation in a shorter time, the temperature of the refrigerant supplied to the evaporator 24 is increased by heating the refrigerant with the heater 37 to evaporate. The frost generated on the surface of the vessel 24 can be melted at an early stage. The amount of heat input by the heater 37 is input into the bathroom 3 by the condenser 20 and used as part of the heat of heating. Since the heater generates heat using a part of the electric power supplied to the compressor 27 and the like, it is relatively small and can easily heat the refrigerant. Therefore, the size and the like of the main body 6 of the ventilation air conditioner are increased. The defrosting operation can be completed in a short time without conversion.

  As described above, with the configuration and operation described above, the ventilation air-conditioning apparatus according to the present embodiment continues heating in the bathroom 3 that is the air-conditioning target room even when the evaporator 24 is in a frosted state during heating operation at low temperatures. Therefore, it is possible to perform the defrosting operation while efficiently heating the air-conditioning target space and improving the convenience for the user.

  Further, the defrosting operation period can be shortened, and the convenience for the user can be improved.

  Moreover, the energy consumption at the time of a defrost operation can be reduced and the ventilation air conditioner of low running cost can be provided.

  In addition, it is possible to provide a ventilation air conditioner that does not require user operation related to the defrosting operation and can perform efficient heating without impairing user convenience.

  The contents described above are only described for one mode for carrying out the invention, and the present invention is not limited to the above embodiment.

  For example, in the present embodiment, when the temperature in the bathroom is low, the amount of decompression in the expansion valve is reduced, the air volume of the circulation fan is increased, the amount of heat absorbed from the air in the bathroom due to the ventilation fan operation, Although described as performing an operation such as heating, there is no problem even if it is performed when the temperature in the bathroom is relatively high in order to shorten the defrosting time, and there is no difference in the effect. Desirably, it is desirable to perform an optimal combination from the viewpoint of shortening the defrosting time and the energy consumed during the defrosting operation.

  In the present embodiment, the method using the heater is described as the means for heating the refrigerant. However, any means capable of heating the refrigerant in the refrigerant circuit may be used, and heat for exchanging heat between the hot water and the refrigerant may be used. Even if an exchanger is installed and a means for heating the refrigerant by passing hot water and the refrigerant is taken, there is no difference in the effect. As shown in this example, when installing a ventilation air conditioner in the bathroom, it is possible to easily use the hot water used in the bathroom, so it is possible to supply a large amount of heat with hot water, The defrosting operation can be completed in a short time. As described above, it is desirable that the refrigerant heating means be easily used as a heat source and highly safe.

  As described above, the ventilation air conditioner according to the present invention can perform the defrosting operation without stopping the heating of the air-conditioning target space during the defrosting operation, shorten the defrosting operation time, and consume the energy consumed. It can be reduced, and can be applied not only to ventilation and air conditioning in bathrooms but also to ventilation and air conditioning devices in living spaces that require ventilation and air conditioning in living rooms and bedrooms.

Schematic of living space in Embodiment 1 of the present invention Schematic of the internal configuration of the ventilation air conditioner body Schematic of refrigerant circuit in the ventilation air conditioner Outline of installation and internal structure of conventional ventilation air conditioner

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Living space 2 Living 3 Bathroom 4 Dressing room 5 Toilet 6 Main body 7 First exhaust duct 8 First exhaust port 9 Second exhaust duct 10 Second exhaust port 11 Third exhaust duct 12 Ventilation fan 13 Air supply port 14 Air conditioner 15 Door 16 Suction port 17 Air outlet 18 Filter 19 First air passage 20 Condenser 21 Circulating fan 22 Second air passage 23 First ventilation port 24 Evaporator 25 Ventilation air outlet 26 Refrigerant circuit 27 Compressor 28 Expansion valve 29 First damper 30 Second damper 31 Defrost air passage 32 Defrost damper 33 Second suction port 34 Third damper 35 Evaporator temperature sensor 36 Suction temperature sensor 37 Heater 101 Indoor unit 102 Condenser 103 Circulating blower 104 Outdoor unit 105 Evaporator 106 Blower Fan 107 Compressor 108 Expansion valve 109 Refrigerant circuit

Claims (22)

A compressor, a condenser, a pressure reducing mechanism, an evaporator, a condenser fan for blowing air from an air-conditioning target room to the condenser, and an evaporator fan for blowing heat absorption target air to the evaporator are used. In the air conditioner for heating the air-conditioning target room by the refrigeration cycle, the air-conditioning target room is heated by passing the air in the air-conditioning target room in the order of the evaporator and the condenser during the defrosting operation of the evaporator. A ventilation air conditioner that performs defrosting of the evaporator while performing. A circulation fan that sucks air from a suction port opened in the first indoor space, which is an air-conditioning target space, and blows out air from a blowout port opened in the first indoor space; and a second indoor space other than the first indoor space A ventilation fan that ventilates by sucking air from the opened exhaust port and discharging it outdoors, a compressor that compresses the refrigerant, a condenser that exchanges heat between the air blown by the circulation fan and the refrigerant, A refrigerant circuit comprising a decompression mechanism that performs decompression and an evaporator that exchanges heat between the air blown by the ventilation fan and the refrigerant, and in which the refrigerant circulates in the order of the compressor, the condenser, the decompression mechanism, and the evaporator In the ventilation air conditioner provided with the defrosting air passage, the defrosting air passage communicating between the evaporator and the condenser, and a defrosting air passage closing means for closing the air flow in the defrost air passage are further provided. Of the evaporator During the frost operation, the air in the air-conditioning target space is blown in the order of the evaporator and the condenser through the defrost air passage so that the evaporator is defrosted while heating the first indoor space. Ventilation air conditioner characterized by doing. The ventilation air conditioner according to claim 2, wherein the defrosting air passage closing means is closed during the heating operation, and the defrosting operation closing means is opened during the defrosting operation. A second suction port for sucking air-conditioning target air in the first indoor space is further provided, and air-conditioning target air is supplied to the condenser by sucking air-conditioning target air from the second suction port during the defrosting operation. The ventilation air conditioner according to claim 2 or 3, wherein The ventilation air conditioner according to claim 4, wherein a first closing mechanism and a second closing mechanism for closing each suction port are provided at the suction port and the second suction port. During the heating operation, the second closing mechanism is closed and the air-conditioning target air is sucked from the intake port, and during the defrosting operation, the first closing mechanism is closed and the air-conditioning target air is sucked from the second intake port. The ventilation air conditioner according to claim 5. The ventilation air conditioner according to any one of claims 1 to 6, wherein ventilation from the second indoor space is stopped during the defrosting operation. A third closing mechanism for closing supply of air from the second indoor space is provided in an exhaust air passage for supplying air in the second indoor space sucked from the exhaust port to the evaporator. The ventilation air conditioner according to claim 7. The ventilation air conditioner according to claim 8, wherein the third closing mechanism is opened during the heating operation, and the third closing mechanism is closed during the defrosting operation. The ventilation air conditioner according to any one of claims 2 to 9, wherein air in the first indoor space is sucked by a circulation fan during the defrosting operation, and is passed in the order of an evaporator and a condenser. During the defrosting operation, the ventilation fan and the circulation fan are operated, and a part of the air-conditioning target air sucked from the first indoor space is ventilated in the order of the evaporator and the condenser, and is circulated and blown into the first indoor space. 3. A part of air to be air-conditioned sucked from a space is exhausted to the outside through the evaporator, thereby increasing an endothermic amount in the evaporator and increasing a temperature of the evaporator. The ventilation air conditioner in any one of Claim 6 or Claim 10. A refrigerant heating means for heating the refrigerant is provided on the refrigerant circuit between the decompression mechanism and the evaporator, and the defrosting time is shortened by heating the refrigerant by the refrigerant heating means during the defrosting operation and the first indoor space. The ventilation air conditioner according to any one of claims 2 to 11, wherein the ventilation air conditioner is heated. The ventilation air conditioner according to claim 12, wherein the refrigerant heating means is a heater for heating by energization. The ventilation air conditioner according to claim 12, wherein the refrigerant heating means is a hot water heat exchanger that heats an object by passing warm water. The ventilation air conditioner according to any one of claims 2 to 14, wherein the flow path of the air in the first indoor space is automatically switched when the evaporator is frosted. The ventilation air conditioner according to claim 15, wherein an evaporator temperature detecting means for detecting the temperature of the evaporator is provided, and frost formation of the evaporator is detected according to the temperature of the evaporator. The ventilation air conditioner according to any one of claims 2 to 16, wherein at the end of defrosting of the evaporator, the flow path of the air in the first indoor space is automatically switched to a ventilation path during normal heating operation. Temperature detecting means for detecting the temperature of the air in the first indoor space is further provided to detect the temperature of the air in the first indoor space, and when the temperature of the air in the first indoor space is low, the pressure is reduced by the pressure reducing mechanism. The ventilation air conditioner according to any one of claims 2 to 17, wherein the amount is reduced. The ventilation air conditioner according to claim 18, wherein when the temperature of the air in the first indoor space exceeds a predetermined temperature, the amount of decompression by the decompression mechanism is increased. The temperature of the air in the first indoor space is detected, and when the temperature of the air in the first indoor space is low, the amount of air blown by the circulation fan is increased. Ventilation air conditioner described in 1. 21. The ventilation air conditioner according to claim 20, wherein when the temperature of the air in the first indoor space exceeds a predetermined temperature, the amount of air blown by the circulation fan is reduced. The ventilation air conditioner according to any one of claims 19 to 21, wherein the temperature detecting means in the first indoor space is provided in an air flow path in the vicinity of the second suction port.

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