Abstract:
An object of the present invention is to provide an outdoor heat exchanger unit which is hardly effected adverse effects of the gas engine waste heat during the cooling operation and which can improve an efficiency of the refrigerant cycle, and which can improve the heating ability by utilizing the gas engine waste heat; an outdoor unit comprising the outdoor heat exchanger unit; and an air conditioner comprising the outdoor heat exchanger unit; in order to achieve the object, the present invention provide an outdoor heat exchanger unit for a gas heat pump type air conditioner, in which a compressor for compressing a refrigerant is driven by a gas engine, and which comprises a heat pump for utilizing waste heat of said gas engine to perform a heating and a cooling operations: wherein said outdoor heat exchanger unit comprises a radiator provided in a cooling water system in which cooling water for said gas engine circulates and an outdoor heat exchanger apparatus provided in a refrigerant circuit in which said refrigerant circulates; said radiator and said outdoor heat exchanger apparatus are arranged in series in the flow direction of an outdoor air introduced in said outdoor heat exchanger unit; said radiator is positioned downstream with respect to said outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in said outdoor heat exchanger unit; and an interval is between said radiator and said outdoor heat exchanger apparatus.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a gas heat pump type air conditioner, in which a compressor for compressing a refrigerant is driven by a gas engine, and which uses waste heat of the gas engine as a heat source for a liquid refrigerant during the heating operation, and an outdoor heat exchanger unit and an outdoor unit, which are suitably used for the gas heat pump type air conditioner. 
     2. Description of the Related Art 
     An air conditioner, in which a heat pump is used for cooling and heating a chamber, is provided with a refrigerant circuit comprising an indoor heat exchanger apparatus, a compressor, an outdoor heat exchanger apparatus, an expansion valve, etc. When the refrigerant circulates in the refrigerant circuit and exchanges heat with air in the indoor heat exchanger apparatus and the outdoor heat exchanger apparatus, the chamber is heated or cooled. In general, the refrigerant absorbs heat from the air in the outdoor heat exchanger apparatus during the heating operation. However, not only the outdoor heat exchanger apparatus but also a refrigerant heat apparatus for heating the refrigerant directly is sometimes provided in the refrigerant circuit. 
     In recent years, an air conditioner has been suggested, which comprises a gas engine, instead of an ordinary motor, as a driving source for the compressor provided in the refrigerant circuit. An air conditioner utilizing a gas engine is called a gas heat pump type air conditioner (abbreviated as “GHP” below). The GHP can use gas, which is relatively cheap, as fuel; therefore, the running cost thereof can be reduced, compared with an air conditioner comprising a compressor driven by the ordinary motor (abbreviated as “EHP” below). 
     Moreover, when waste heat of gas at a high temperature discharged from the gas engine during the heating operation is used as the heat source for the refrigerant in the GHP, the heating ability can be improved, and the use efficiency of energy can also be improved. When the temperature of the outdoor air is low, the heating ability of the GHP is 1.2 to 1.5 times as large as the heating ability of the EHP. In addition, when the waste heat of the gas discharged from the gas engine is used in the GHP, the GHP does not require a special device, such as the refrigerant heating device explained above. 
     Furthermore, the GHP can utilize the engine waste heat to defrost the outdoor heat exchanger apparatus during the heating operation. In general, the EHP defrosts the outdoor heat exchanger apparatus by stopping the heating operation and temporarily performing the cooling operation. That is, when the EHP defrosts, cooled air is introduced into the chamber. Therefore, a person in the chamber feels unpleasant. In contrast, the GHP can utilize the waste heat, and it can continuously perform the heating operation without such a problem which is caused by the EHP. 
     The GHP has many advantages as explained above; however, it also has the following problems. 
     FIG. 8 shows a conventional outdoor heat exchanger unit. In FIG. 8, reference number  23  denotes a heat exchanger chamber which is positioned in the upper portion of an outdoor unit,  81  denotes an outdoor fan for introducing outdoor air, and  2  denotes an outdoor heat exchanger unit for exchanging heat between the refrigerant and the outdoor air. The outdoor heat exchanger unit  2  comprises three heat exchangers arranged in series in the flow direction of the outdoor air. Specifically, a radiator  53  is arranged in the center of the outdoor heat exchanger unit  2 , and two heat exchangers  31  and  31  sandwich the radiator  53  so as to be positioned upstream and downstream of the flow direction of the outdoor air with respect to the radiator  53 . The radiator  53  belongs to a cooling water circuit in which cooling water for the gas engine circulates. As shown in FIG. 8B, the radiator  53  and the two heat exchangers  31  and  31  divide a fin  3 . In other words, fins of the radiator  53  and the heat exchangers  31  and  31  are integrated as the fin  3 . 
     In order to improve the heating ability when the temperature of the outdoor air is low, the outdoor heat exchanger unit  2  adopts such a three heat exchanger sandwiched structure. The outdoor heat exchanger unit  2  functions as an evaporator during the heating operation. In the outdoor heat exchanger unit  2 , the heat exchangers  31  and  31  can absorb the waste heat radiated from the radiator  53 . Therefore, even when the temperature of the outdoor air is low, the outdoor heat exchanger unit  2  can obtain heat required for evaporating the refrigerant from the waste heat of the gas engine. 
     In contrast, the outdoor heat exchanger unit  2  functions as a condenser during the cooling operation The waste heat of the gas engine, which is radiated from the radiator  53 , decreases the efficiency of the refrigerant cycle. In other words, the heat exchangers  31  and  31  as condensers are effected by the waste heat from the radiator  53 , and the pressure in the refrigerant cycle increases. Therefore, a large amount of electric power is required to drive the compressor, and the coefficient of performance (COP) of the air conditioner decreases. Moreover, the COP is calculated from the following formula: COP=Qe/L, wherein Qe is the refrigeration capacity, and L is the electric power required for the compressor. Therefore, an outdoor heat exchanger unit has been desired, which can improve the efficiency of the refrigerant cycle without being effected by the engine waste heat during the cooling operation. Moreover, an outdoor heat exchanger unit has also been desired which can improve the efficiency of the refrigerant cycle during the cooling operation and the heating ability by using the gas engine waste heat when the temperature of the outdoor air is low. Furthermore, the development of an outdoor unit comprising the outdoor heat exchanger unit and a GHP comprising the outdoor heat exchanger unit has also been desired. 
     Therefore, an object of the present invention is to provide: an outdoor heat exchanger unit which is hardly effected by the gas engine waste heat during the cooling operation thereby improving the efficiency of the refrigerant cycle, and which can improve the heating ability by utilizing the gas engine waste heat; an outdoor unit comprising the outdoor heat exchanger unit; and a GHP comprising the outdoor unit. 
     SUMMARY OF THE INVENTION 
     In order to achieve the object, the present invention provides an outdoor heat exchanger unit for a GHP, in which a compressor for compressing a refrigerant is driven by a gas engine, and which comprises a heat pump for utilizing waste heat of the gas engine to perform a heating and a cooling operations: 
     wherein the outdoor heat exchanger unit comprises a radiator provided in a cooling water system in which cooling water for the gas engine circulates and an outdoor heat exchanger apparatus provided in a refrigerant circuit in which the refrigerant circulates; 
     the radiator and the outdoor heat exchanger apparatus are arranged in series in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit; 
     the radiator is positioned downstream with respect to the outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit; and 
     an interval is between the radiator and the outdoor heat exchanger apparatus. 
     In the outdoor heat exchanger unit, the interval is between the radiator and the outdoor heat exchanger apparatus; therefore, heat is not conducted between the outdoor heat exchanger apparatus and the radiator. Moreover, the radiator is positioned downstream with respect to the outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit. Therefore, the outdoor air heated by the radiator does not pass through the outdoor heat exchanger apparatus. As a result, it is possible to prevent the outdoor heat exchanger apparatus from being effected by adverse effects of the waste heat of the gas engine during the cooling operation. Moreover, the COP can be improved. 
     In order to achieve the object, the present invention provides an outdoor unit for a GHP, in which a compressor for compressing a refrigerant is driven by a gas engine, and which comprises a heat pump for utilizing waste heat of the gas engine to perform a heating and a cooling operations: 
     wherein the outdoor unit comprises a gas engine portion comprising the gas engine, a cooling water system comprising a radiator, an exhaust gas system for introducing exhaust gas discharged from the gas engine into outside of the outdoor unit, and a fuel intake system for supplying fuel and air in the gas engine; and a refrigerant circuit comprising the compressor, an outdoor heat exchanger apparatus for exchanging heat between the refrigerant and air introduced therein, and an expansion valve for decompressing and expanding the refrigerant in a liquid state during the cooling operation; and 
     an outdoor heat exchanger unit is provided in the outdoor unit, in which the radiator and the outdoor heat exchanger apparatus are arranged in series in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit; the radiator is positioned downstream with respect to the outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit; and an interval is between the radiator and the outdoor heat exchanger apparatus. 
     The outdoor unit comprises the outdoor heat exchanger unit in which the interval is between the radiator and the outdoor heat exchanger apparatus; therefore, heat is not conducted between the outdoor heat exchanger apparatus and the radiator. Moreover, the radiator is positioned downstream with respect to the outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit. Therefore, the outdoor air heated by the radiator does not pass through the outdoor heat exchanger apparatus. As a result, it is possible to prevent the outdoor heat exchanger apparatus from being effected by adverse effects of the waste heat of the gas engine during the cooling operation. Moreover, the COP can be improved. 
     In order to achieve the object, the present invention provides a GHP, in which a compressor for compressing a refrigerant is driven by a gas engine, and which comprises a heat pump for utilizing waste heat of the gas engine to perform a heating and a cooling operations: 
     wherein the GHP comprises an outdoor unit and an indoor unit; 
     the outdoor unit comprises a gas engine portion comprising the gas engine, a cooling water system comprising a radiator, an exhaust gas system for introducing exhaust gas discharged from the gas engine into outside of the outdoor unit, and a fuel intake system for supplying fuel and air in the gas engine; a refrigerant circuit comprising the compressor, an outdoor heat exchanger apparatus for exchanging heat between the refrigerant and air introduced therein, and an expansion valve for decompressing and expanding the refrigerant in a liquid state during the cooling operation; 
     an outdoor heat exchanger unit is provided in the outdoor unit, in which the radiator and the outdoor heat exchanger apparatus are arranged in series in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit; the radiator is positioned downstream with respect to the outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit; and an interval is between the radiator and the outdoor heat exchanger apparatus; and 
     an indoor unit comprises a fan for drawing indoor air and blowing out it from an opening, and an indoor heat exchanger apparatus for exchanging heat between the refrigerant supplied from the outdoor unit and the indoor air drawn by the fan. 
     The GHP comprises the outdoor unit provided with the outdoor heat exchanger unit in which the interval is between the radiator and the outdoor heat exchanger apparatus; therefore, heat is not conducted between the outdoor heat exchanger apparatus and the radiator. Moreover, the radiator is positioned downstream with respect to the outdoor heat exchanger apparatus in the flow direction of an outdoor air introduced in the outdoor heat exchanger unit. Therefore, the outdoor air heated by the radiator does not pass through the outdoor heat exchanger apparatus. As a result, it is possible to prevent the outdoor heat exchanger apparatus from being effected by adverse effects of the waste heat of the gas engine during the cooling operation. Moreover, the COP can be improved. 
     In the GHP, it is preferable that it further comprises a fan for introducing outdoor air into outdoor heat exchanger unit; the fan rotates in a normal mode so as to introduce outdoor air through the outdoor heat exchanger apparatus and radiator in turn during the cooling operation; and the fan rotates in a reverse mode so as to introduce outdoor air through the radiator and the outdoor heat exchanger apparatus in turn during the heating operation. 
     The GHP is not effected by adverse effects of the waste heat of the gas engine during the cooling operation. In contrast, the heating ability can be improved by utilizing the waste heat of the gas engine during the heating operation. 
     In the GHP, it is possible that it further comprises a water heat exchanger apparatus for absorbing waste heat of the gas engine from cooling water circulating in the cooling water system and evaporating the refrigerant; and a constant pressure expansion valve is used as the expansion valve. 
     According to the GHP, a pressure decrease in the circulating refrigerant can be prevented, and frost of the outdoor heat exchanger apparatus can be prevented. Therefore, when the efficiency of the gas engine is improved, and thereby the waste heat of the gas engine decreases; a decrease in the heating ability can be prevented. 
     In the GHP, it is preferable that the outdoor heat exchanger apparatus comprises at least three heat exchangers arranged in series in the flow direction of outdoor air introduced into an outdoor heat exchanger unit; at least one heat exchanger which is not arranged at both sides of the outdoor heat exchanger apparatus is a warm water heat exchanger belongs to the cooling water system; and the cooling water system further comprises a valve for selectively introducing cooling water of the gas engine into the warm water heat exchanger. 
     According to the GHP, the valve is closed during the cooling operation, and thereby the cooling water for the gas engine does not pass through the warm water heat exchanger. Therefore, the outdoor heat exchanger apparatus is not effected by adverse effects of the waste heat In contrast, during the heating operation, the valve is opened, and thereby the cooling water for the gas engine passes through the radiator and the warm water heat exchanger. Therefore, the refrigerant can absorb heat sufficient for evaporation from the waste heat of the cooling water for the gas engine. 
     Moreover, in the GHP, it is more preferable that the valve is operated so as to introduce the cooling water into the warm water heat exchanger depending on conditions under which frost is generated in the outdoor heat exchanger apparatus during the heating operation and temperature of outdoor air is low. 
     According to the GHP, it is possible to prevent the outdoor heat exchanger apparatus from frosting. Therefore, a decrease in the heating ability can be prevented. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is a perspective view showing a first embodiment of the outdoor heat exchanger unit according to the present invention. 
     FIG. 1B shows the outdoor heat exchanger unit viewed from the direction indicated by the A-arrow in FIG.  1 A. 
     FIG. 2 is a block diagram showing a first embodiment of the GHP according to the present invention. 
     FIG. 3 shows an internal constitution of a first embodiment of the outdoor unit according to the present invention. 
     FIG. 4 shows a side view of the internal constitution of the outdoor unit shown in FIG.  3 . 
     FIG. 5A shows an flow direction of the outdoor air in the outdoor heat exchanger unit in the cooling operation. 
     FIG. 5B shows an flow direction of the outdoor air in the outdoor heat exchanger unit in the heating operation. 
     FIG. 6A is a perspective view showing another embodiment of the outdoor heat exchanger unit according to the present invention. 
     FIG. 6B shows a girder provided in the outdoor heat exchanger unit shown in FIG.  6 A. 
     FIG. 7 is a block diagram showing a second embodiment of the GHP according to the present invention. 
     FIG. 8A is a schematic view showing the main portion of the conventional outdoor heat exchanger unit. 
     FIG. 8B is a partial enlarged view showing the fin provided in the conventional outdoor heat exchanger unit. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring the FIGS. 1 to  7 , preferred embodiments of the outdoor heat exchanger unit, the outdoor unit, and the GHP according to the present invention will be explained below. 
     A first embodiment of the present invention will be explained referring to FIGS. 1 to  6 . FIG. 2 is a block diagram showing a first embodiment of the GHP. The GHP comprises an indoor unit  10  and an outdoor unit  20  as main components. The indoor unit  10  comprises an indoor heat exchanger apparatus  11 . During the cooling operation, the indoor heat exchanger apparatus  11  evaporates a liquid refrigerant of low temperature and low pressure, and thereby absorbs heat from the indoor air, that is, it cools the indoor air. During the heating operation, the indoor heat exchanger apparatus  11  condenses and liquefies a gas refrigerant of high temperature and high pressure, and thereby discharges heat to the indoor air, that is, it warms the indoor air. Moreover, the indoor air is drawn into the indoor heat exchanger apparatus  11  by an indoor fan  12 . After the indoor air exchanges heat with a refrigerant in the indoor heat exchanger apparatus  11 , it is blown out into a chamber. 
     The outdoor unit  20  comprises a refrigerant circuit  30  and a gas engine portion  40  provided with a gas engine  41  and auxiliary equipment, as main components. 
     The refrigerant circuit  30  comprises an outdoor heat exchanger apparatus  31 , a water heat exchanger apparatus  32 , a compressor  33 , an accumulator  34 , a four-way valve  35 , an oil separator  36 , an expansion valve  37 , and a three-way valve  38 . 
     During the cooling operation, the outdoor heat exchanger apparatus  31  condenses and liquefies a gas refrigerant of high temperature and high pressure, that is, it discharges heat of the gas refrigerant into the outdoor air. During the heating operation, the outdoor heat exchanger apparatus  31  evaporates a liquid refrigerant of low temperature and low pressure, that is, it absorbs heat from the outdoor air. In other words, the function of the outdoor heat exchanger apparatus  31  during the heating operation is the same as the function of the indoor heat exchanger apparatus  11  during the cooling operation. Moreover, the function of the outdoor heat exchanger apparatus  31  during the cooling operation is the same as the function of the indoor heat exchanger apparatus  11  during the heating operation. 
     In the water heat exchanger apparatus  32 , the refrigerant absorbs waste heat from the cooling water for the gas engine  41 . That is, the refrigerant absorbs heat not only from the outside air in the outdoor heat exchanger apparatus  31  but also from the cooling water for the gas engine  41  in the water heat exchanger apparatus  32 , during the heating operation. Therefore, the efficiency of the heating operation can be improved. 
     The compressor  33  compresses a gas refrigerant flowing therein from either the indoor heat exchanger apparatus  11  or the outdoor heat exchanger apparatus  31 , and discharges the gas refrigerant as a gas refrigerant of high temperature and high pressure. Due to the functions of the compressor  33 , even when the temperature of the outdoor air is high, the refrigerant can radiate heat into the outdoor air through the outdoor heat exchanger apparatus  31  during the cooling operation. In contrast, the refrigerant can give heat to the indoor air through the indoor heat exchanger apparatus  11  during the heating operation. 
     The accumulator  34  separates out a liquid component contained in the gas refrigerant flowing into the compressor  33 , and accumulates a surplus refrigerant generated depending on the operation conditions of the indoor unit  10 . 
     The four-way valve  35  selectively flows the gas refrigerant of high temperature and high pressure compressed in the compressor  33  into either the indoor heat exchanger apparatus  11  or the outdoor heat exchanger apparatus  31 . 
     The oil separator  36  separates out an oil, such as a lubricating oil used in the compressor  33 , which is contained in the refrigerant. 
     The expansion valve  37  decompresses and expands the liquid refrigerant of high temperature and high pressure flowing out from the outdoor heat exchanger apparatus  31 , and thereby, changes the liquid refrigerant of high temperature and high pressure into a liquid refrigerant of low temperature and low pressure during the cooling operation. 
     The three-way valve  38  introduces the refrigerant into the water heat exchanger apparatus  32  during the heating operation, and introduces the refrigerant into a by-pass circuit  30   a  during the cooling operation. 
     The gas engine portion  40  comprises the gas engine  41  as a main component, and further comprises a cooling water system  50 , an exhaust gas system  60 , a fuel intake system  70 , and an engine oil system which is not shown in the figures. 
     The gas engine  41  connects to the compressor  33  provided in the refrigerant circuit  30  by a shaft or a belt; therefore, a motive power force is transferred from the gas engine  41  to the compressor  33 . 
     The cooling water system  50  comprises a water pump  51 , a reserve tank  52 , and a radiator  53 , and it cools the gas engine  41  by cooling water circulating in a circuit comprising these components  51 ,  52 , and  53 . 
     The water pump  51  circulates the cooling water for the gas engine  41  in the circuit. 
     The reserve tank  52  temporarily accumulates surplus cooling water circulating in the circuit, or supplies the surplus cooling water into the circuit when the cooling water is insufficient. 
     The radiator  53  is integrated with the outdoor heat exchanger apparatus  31 . The radiator  53  radiates heat of the cooling water, which is absorbed from the gas engine  41 , into the outdoor air. Moreover, the unit, in which the radiator  53  and the outdoor heat exchanger apparatus  31  are integrated, is called an outdoor heat exchanger unit  100  below. The detailed structure of the outdoor heat exchanger unit  100  will be explained below. 
     An exhaust gas heat exchanger  54  is also provided in the cooling water system  50 . In the exhaust gas heat exchanger  54 , the cooling water absorbs waste heat of an exhaust gas exhausted from the gas engine  41 . The waterheat exchanger apparatus  32 , which was explained above, also belongs to the cooling water system  50 . That is, the water heat exchanger apparatus  32  belongs to both the refrigerant circuit  30  and the cooling water system  50 . Due to this construction, the cooling water absorbs heat from not only the gas engine  41 , but also the exhaust gas. The waste heat absorbed in the cooling water is conducted to the refrigerant in the water heat exchanger apparatus  32 . 
     The exhaust gas system  60  comprises a muffler  61 , an exhaust top  62 , and a drain filter  63 . The exhaust gas system  60  releases the gas exhausted from the gas engine  41  to the outside of the outdoor unit  20 . 
     The muffler  61  absorbs noise generated when exhausting the gas from the gas engine  41 . 
     The exhaust top  62  separates out moisture contained in the exhaust gas, and prevents the moisture from being discharged to the outside of the outdoor unit  20 . The exhaust top  62  can also be called an exhaust gas separator. 
     The drain filter  63  temporarily accumulates the moisture separated from the exhaust gas in the exhaust top  62 . Moreover, a neutralizer is contained in the drain filter  63 , in order to neutralize the moisture contained in the exhaust gas, which is a strong acid, in general. 
     The fuel intake system  70  comprises a gas regulator  71 , an electrical valve  72 , an intake chamber  73 , and an air cleaner  74 . The fuel intake system  70  supplies fuel and air into the gas engine  41 . 
     The gas regulator  71  adjusts the delivery pressure of the gas supplied from the outside of the outdoor unit  20  via the electrical valve  72 . 
     The intake chamber  73  introduces air for combustion from the outside of the outdoor unit  20 . Moreover, the intake chamber  73  also prevents the generation of noise when the intake chamber  73  takes in air from the outside of the outdoor unit  20 . 
     The air cleaner  74  cleans dust from the air taken in by the intake chamber  73 . 
     As explained above, the gas and the air supplied from the outside of the outdoor unit  20  pass through the gas regulator  71  and the air cleaner  74 , and then they are mixed. Thereafter, the mixture is sent into the gas engine  41  as fuel. 
     These devices and systems comprising the outdoor unit  20  are contained in an outdoor unit body  21 , as shown in FIGS. 3 and 4. As shown in FIGS. 3 and 4, the inside of the outdoor unit body  21  is divided into top and bottom parts by a partition  22 . Below, the top part of the outdoor unit body  21  is called a heat exchange chamber  23 , and the bottom part thereof is called a machine chamber  24 . Moreover, the pipes, which are explained referring to FIG. 2, are omitted in FIGS. 3 and 4. 
     First, the heat exchange chamber  23  will be explained below. In the heat exchange chamber  23 , the outdoor heat exchanger unit  100 , in which the outdoor heat exchanger apparatus  31  and the radiator  53  are integrated, is positioned so as to cover the front and the back faces of the outdoor unit body  21 . In addition to the outdoor heat exchanger unit  100 , for example, the muffler  61 , the exhaust top  62 , and the intake chamber  73  are positioned in the heat exchange chamber  23 . Moreover, the muffler  61 , the exhaust top  62 , and a pipe  60   a , which connects the muffler  61  and the exhaust top  62 , are shown in FIG. 3; however, they are omitted in FIG.  4 . 
     Outdoor fans  81  and  81 , fan motors  82  and  82 , and fan fixtures  83  and  83  are provided in the heat exchange chamber  23 , in addition to the outdoor heat exchanger unit  100 , the muffler  61 , the exhaust top  62 , etc. The outdoor fan  81  is provided with a power output shaft of the fan motor  82  fixed to the fan fixture  83  which is suspended from the ceiling of the outdoor unit body  21 . Two sets comprising the outdoor fan  81 , the fan motor  82 , and the fan fixture  83  are provided in the heat exchange chamber  23  in this embodiment. Moreover, openings  84  and  84  for the outdoor fans  81  and  81  are provided at the ceiling of the outdoor unit body  21 . Net covers  85  and  85  are provided at the openings  84  and  84 . The outdoor fan  81  can change its rotation direction in response to the operation of the GHP  1 . That is, the rotation direction of the outdoor fan  81  during the heating operation is different from that during the cooling operation. Thereby, the flow direction of the outdoor air introduced into the outdoor heat exchanger unit  100  can be changed; therefore, the operation of the outdoor heat exchanger apparatus  31  can be assisted. 
     Furthermore, two ventilation chambers  86  and  86  are provided on the partition  22 , and ventilation fans  87  and  87  are provided in the ventilation chambers  86  and  86 . The ventilation chamber  86  and the ventilation fan  87  introduce heat generated in the machine chamber  24  into the heat exchange chamber  23 . Therefore, the air heated in the machine chamber  24 , in which the gas engine  41  operates, is introduced into the heat exchange chamber  23  by the ventilation fan  87 , and discharged to the outside of the outdoor unit body  21  by the outdoor fan  81 . 
     The intake chambers  73  and  73  are positioned on the ventilation chambers  86  and  86 . The air taken in by the intake chamber  73  passes through the ventilation chamber  86  and reaches the gas engine  41 . 
     Next, the machine chamber  24  will be explained. Almost all of the devices and the systems comprising the GHP, which were explained referring to FIG. 2, are contained in the machine chamber  24 . For example, FIGS. 3 and 4 show only the compressor  33 , the accumulator  34 , the four-way valve  35 , and the oil separator  36 , which belong to the refrigerant circuit  30 ; and the gas engine  41 , the drain filter  63 , and the air cleaner  74 , which belong to the gas engine portion  40 . 
     In addition to these devices, a drain pipe  91  is also provided in the machine chamber  24 . The drain pipe  91  connects an opening  22   a , which is formed at the partition  22 , and an opening  25 , which is formed at the floor of the outdoor unit body  21 . The drain pipe  91  discharges rainwater, which falls to the outdoor unit body  21  through the opening  84  formed at the ceiling, into the outside of the outdoor unit body  21 . 
     Moreover, a base plate  92  and vibration proof rubber parts  93  and  93  are provided in the machine chamber  24 . The base plate  92  is substantially in a square shape, and it is used as a floor board on which to place the components comprising the refrigerant circuit  30  and the gas engine portion  40 , which are in the machine chamber  24 . The vibration proof rubber parts  93  and  93  are positioned at the four corners of the bottom surface of the base plate  92 . The base plate  92  and the vibration proof rubber parts  93  and  93  prevent vibrations due to the refrigerant circuit  30  and the gas engine portion  40 . 
     Below, the preferred embodiment of the outdoor heat exchanger unit  100  will be explained referring to FIGS. 1A and 1B. 
     As explained above, the outdoor heat exchanger apparatus  31 , in which the refrigerant flows, and the radiator  53 , in which the cooling water for the gas engine  41  flows, are integrated in the outdoor heat exchanger unit  100 . The refrigerant and the cooling water exchange heat with the outdoor air introduced by the outdoor fan  81  into the outdoor heat exchanger unit  100 . The outdoor heat exchanger apparatus  31  and the radiator  53  are arranged in series in the flow direction of the outdoor air. There is an interval  101  between the outdoor heat exchanger apparatus  31  and the radiator  53 . In the outdoor heat exchanger unit  100  shown in FIG. 1B, the radiator  53  is arranged at the downstream side with respect to the outdoor heat exchanger apparatus  31  in the flow direction of the introduced air during the cooling operation. The preferable width of the interval  101  varies depending on various conditions; however, it is preferably about 2 mm. 
     As shown in FIG. 1A, the outdoor heat exchanger apparatus  31  and the radiator  53 , each of which has individual fins, are integrated by fixing the right and the left ends thereof using end plates  102  and  103 . In other words, the interval  101  is between the fins  31   a  of the outdoor heat exchanger apparatus  31  and the fins  53   a  of the radiator  53 . These fins  31   a  and  53   a  are separated, and are individual. Heat cannot be conducted between the fins  31   a  and the fins  53   a . Moreover, reference number  104  denotes intermediate girders. The intermediate girders  104  and  104  are positioned between the end plates  102  and  103  maintaining a suitable interval, if necessary. Moreover, reference number  31   b  denotes a copper pipe which is used as a refrigerant passage, and  53   b  denotes a copper pipe which is used as a cooling water passage. 
     As explained above, the preferred embodiment of the outdoor heat exchanger unit  100 , in which the outdoor heat exchanger apparatus  31  and the radiator  53  are integrated, is shown in FIG.  1 . However, an outdoor heat exchanger unit  100 , which is shown in FIG. 6, can also be suitably used. 
     In this outdoor heat exchanger unit  100 , the outdoor heat exchanger apparatus  31  has a pair of end plates  110  and  111 , and the radiator  53  also has a pair of end plates  112  and  113 . These end plates  110 ,  111 ,  112 , and  113  respectively have ribs. Intermediate girders  114  and  114 , which comprise fixing plates at the upper and lower ends thereof, are interposed between the end plates  110  and  111 . Intermediate girders  115  and  115 , which comprise fixing plates  115   a  and  115   b  at the upper and lower ends thereof, are also interposed between the end plates  112  and  113 . The fixing plates  115   a  and  115   b , which are provided with the intermediate girder  115 , are positioned perpendicular to the intermediate girder  115  and parallel to the end plates  112  and  113 . The fixing plates  115   a  and  115   b  are superposed on the fixing plates of the intermediate girder  114 . As shown in FIG. 1A, the outdoor heat exchanger apparatus  31  and the radiator  53  are integrated maintaining the interval  101  between them by superposing and screwing together the ribs of the end plates  110  and  111  of the outdoor heat exchanger apparatus  31  and the end plates  112  and  113  of the radiator  53 , and by fixing and screwing the fixing plates  115   a  and  115   b  of the intermediate girder  115  and the fixing plates of the intermediate girder  114  using screws  117  and  117 . 
     Below, the components of the GHP  1  will be explained by classifying the operations of the GHP  1  into a heating operation and a cooling operation. 
     First, the components of the GHP  1  during the cooling operation will be explained. During the cooling operation, the four-way valve  35  connects the compressor  33  and the outdoor heat exchanger apparatus  31 , and connects the indoor heat exchanger apparatus  11  and the accumulator  34 . The flow direction of the refrigerant during the cooling operation is shown by an arrow with a solid line in FIG.  2 . As shown in FIG. 2, a gas refrigerant of high temperature and high pressure, which is discharged from the compressor  33 , flows into the outdoor heat exchanger apparatus  31 . Moreover, the three-way valves  38  and  38  make the refrigerant pass through the by-pass circuit  30   a , in order to prevent the refrigerant from passing through the water heat exchanger apparatus  32  during the cooling operation. 
     The gas refrigerant of high temperature and high pressure discharges heat into the outdoor air and is condensed in the outdoor heat exchanger apparatus  31 , and it becomes a liquid refrigerant of high temperature and high pressure. Then, the liquid refrigerant of high temperature and high pressure is decompressed when the refrigerant passes through the expansion valve  37 , and it becomes a liquid refrigerant of low temperature and low pressure. Thereafter, the liquid refrigerant is sent into the indoor unit  10 . 
     The liquid refrigerant of low temperature and low pressure absorbs heat from the indoor air, and is vaporized in the indoor heat exchanger apparatus  11 . Thereby, the chamber is cooled and the liquid refrigerant becomes a gas refrigerant of low temperature and low pressure. Then, the gas refrigerant is sent into the refrigerant circuit  30  in the outdoor unit  20 . 
     The refrigerant passes through the four-way valve  35 , and flows into the accumulator  34 . When the refrigerant contains a liquid component, the liquid component is separated out in the accumulator  34 . The gas refrigerant containing no liquid component flows into the compressor  33 . The gas refrigerant is compressed in the compressor  33 , and then it becomes a gas refrigerant of high temperature and high pressure. Thereafter, the gas refrigerant is sent into the outdoor heat exchanger apparatus  31  again. 
     As explained above, the outdoor heat exchanger apparatus  31  of the outdoor heat exchanger unit  100  acts as a condenser during the cooling operation. Namely, the outdoor heat exchanger apparatus  31  discharges heat of the refrigerant to the outdoor air introduced therein. Therefore, the waste heat of the gas engine  41  radiated from the radiator  53  causes adverse effects on the outdoor heat exchanger apparatus  31 . In other words, when the outdoor heat exchanger apparatus  31 , which acts as a condenser, is heated due to the waste heat of the gas engine  41 , the pressure of the refrigerant of the refrigerant circuit  30  increases, and a large amount of electric power is required to drive the compressor. As a result, the COP of the GHP decreases. This is unsuitable for the cooling operation. 
     However, the radiator  53  is positioned at the downstream side with respect to the outdoor heat exchanger apparatus  31  in the flow direction of the introduced outdoor air as shown in FIG. 5A in this embodiment. During the cooling operation, the outdoor fan  81  rotates in a normal mode. That is, the outdoor fan  81  rotates so as to draw in the outdoor air from both sides of the heat exchange chamber  23 , and discharges the outdoor air from the opening  84  formed at the ceiling. Due to this, the outdoor air heated by the radiator  53  does not pass through the outdoor heat exchanger apparatus  31 . That is, the outdoor heat exchanger apparatus  31  is not heated by the outdoor air heated by the radiator  53 . In addition, the interval  101  is between the fins  31   a  of the outdoor heat exchanger apparatus  31  and the fins  53   a  of the radiator  53 ; therefore, heat is not conducted between the outdoor heat exchanger apparatus  31  and the radiator  53 . As a result, it is possible to prevent the outdoor heat exchanger apparatus  31  from being effected by adverse effects of the waste heat of the gas engine  41 . 
     In the outdoor heat exchanger unit  100 , the outdoor heat exchanger apparatus  31 , which acts as a condenser, does not absorb the waste heat from the radiator  53 , and the pressure in the refrigerant cycle does not increase. Therefore, a large amount of electric power is not required to drive the compressor  33 , and the COP of the GHP can be improved. 
     Moreover, the outdoor heat exchanger apparatus  31  is not effected by adverse effects of the radiator  53 , and it can have a small size. The manufacturing cost can be reduced, and the GHP can also have a small size. 
     Below, the components of the GHP  1  during the heating operation will be explained. During the heating operation, the four-way valve  35  connects the compressor  33  and the indoor heat exchanger apparatus  11 , and connects the outdoor heat exchanger apparatus  31  and the accumulator  34 . The flow direction of the refrigerant during the heating operation is shown by an arrow with a broken line in FIG.  2 . As shown in FIG. 2, a gas refrigerant of high temperature and high pressure, which is discharged from the compressor  33 , flows into the indoor heat exchanger apparatus  11  of the indoor unit  10 . 
     The gas refrigerant of high temperature and high pressure discharges heat into the indoor air, and it is condensed and becomes a liquid refrigerant of high temperature and high pressure in the indoor heat exchanger apparatus  11 . Thereby, the camber is heated. Then, the liquid refrigerant of high temperature and high pressure is sent into the refrigerant circuit  30  in the outdoor unit  20 . The liquid refrigerant flows into the outdoor heat exchanger apparatus  31 . The liquid refrigerant of high temperature and high pressure absorbs heat from the outdoor air and is evaporated; then it becomes a gas refrigerant of low temperature and low pressure. 
     Moreover, the three-way valves  38  and  38  make the refrigerant pass through the water heat exchanger apparatus  32  during the heating operation. Therefore, the gas refrigerant of low temperature and low pressure flows into the water heat exchanger apparatus  32 , and exchanges heat with the cooling water of the gas engine  41 . Thereby the gas refrigerant of low temperature and low pressure becomes a gas refrigerant of high temperature and high pressure. The refrigerant flows into the accumulator  34 . When the refrigerant contains a liquid component, the liquid component is separated out in the accumulator  34 . The gas refrigerant containing no liquid component flows into the compressor  33 . The gas refrigerant is compressed in the compressor  33 , and then it becomes a gas refrigerant of high temperature and high pressure. Thereafter, the gas refrigerant is sent into the indoor heat exchanger apparatus  11  again. 
     During the heating operation, when the temperature of the outdoor air is relatively high, the refrigerant can absorb heat from the outdoor air sufficient for evaporation in the outdoor heat exchanger apparatus  31 , and problems do not particularly arise. However, when the temperature of the outdoor air is low, for example when the GHP  1  is used in a cold region, it is difficult for the refrigerant to absorb heat sufficiently from the outdoor air. Therefore, the heating ability sometimes decreases. In particular, the outdoor air passes through the outdoor heat exchanger apparatus  31  and then passes through the radiator  53 ; the outdoor heat exchanger apparatus  31  and the radiator  53  are separated in this embodiment. Therefore, the waste heat of the gas engine  41  does not effect the outdoor heat exchanger apparatus  31 . Namely, the waste heat of the gas engine  41  cannot be utilized in this embodiment. 
     When the temperature of the outdoor air is low and the GHP performs the heating operation, the outdoor fan  81  rotates in a reverse mode. That is, the outdoor fan  81  rotates so as to introduce the outdoor air into the heat exchange chamber  23  from the opening  84  formed at the ceiling, as shown in FIG.  5 B. The outdoor air, which is introduced into the heat exchange chamber  23 , passes through the radiator  53  and the outdoor heat exchanger apparatus  31  in turn, and it is discharged from both sides of the heat exchange chamber  23 . 
     Due to this, the outdoor air is heated by the waste heat of the gas engine  41  when it passes through the radiator  53 . The heated outdoor air flows into the outdoor heat exchanger apparatus  31 , and exchanges heat with the refrigerant. Therefore, even when the temperature of the outdoor air is low, the refrigerant can absorb heat sufficient for evaporation from the outdoor air. That is, the waste heat of the gas engine  41  can be utilized, and thereby the heating ability can be improved. 
     Moreover, the rotation direction of the outdoor fan  81  may be changed in response to the temperature of the outdoor air, in addition to the heating operation conditions. 
     Furthermore, when the GHP  1  comprises the water heat exchanger apparatus  32 , the expansion valve  37 , which is positioned between the indoor heat exchanger apparatus  11  and the outdoor heat exchanger apparatus, is preferably a constant pressure expansion valve. When the expansion valve  37  is a constant pressure expansion valve, a pressure decrease in the circulating refrigerant can be prevented. In other words, when the temperature of the outdoor air is low, the efficiency of the gas engine  41  is improved, and thereby the waste heat of the gas engine  41  decreases; a pressure decrease in the circulating refrigerant can be prevented. Consequently, a temperature decrease in the refrigerant can be prevented. Therefore, frost of the outdoor heat exchanger apparatus  31  can be prevented by using a constant pressure expansion valve. As a result, a decrease in the heating ability can be prevented. 
     Below a second embodiment of the GHP according to the present invention will be explained referring to FIG.  7 . 
     FIG. 7 shows the main components comprising the refrigerant circuit  30  and the gas engine portion  40 , which belong to the outdoor unit  20 , and the indoor heat exchanger apparatus  11 . An outdoor heat exchanger apparatus  31 A, which comprises three heat exchangers arranged in series in the flow direction of the outdoor air introduced into an outdoor heat exchanger unit  100 A, is provided in the GHP  1  of this embodiment. 
     A heat exchanger, which is centered in the outdoor heat exchanger apparatus  31 A, is a warm water heat exchanger  120 , and belongs to the cooling water system  50 . The remaining two heat exchangers, which sandwich the warm water heat exchanger  120 , are refrigerant heat exchangers  121  and  121 , and belongs to the refrigerant circuit  30 . 
     The outdoor heat exchanger apparatus  31 A is arranged upstream with respect to the radiator  53  in the flow direction of the air introduced in the outdoor heat exchanger unit  100 A. Moreover, the interval  101  is between the outdoor heat exchanger apparatus  31 A and the radiator  53 . 
     A valve  122  for selectively introducing the cooling water of the gas engine  41  into the warm water heat exchanger  120  is arranged upstream with respect to the warm water heat exchanger  120  in the flow direction of the cooling water of the gas engine  41 . Namely, the valve  122  is arranged between the gas engine  41  and the outdoor heat exchanger apparatus  31 A. In particular, an electrical valve is suitably used as the valve  122 . 
     During the cooling operation, the valve  122  is closed, and thereby the cooling water for the gas engine  41  passes through only the radiator  53 . Namely, the cooling water for the gas engine  41  does not pass through the warm water heat exchanger  120 . As a result, only the refrigerant heat exchangers  121  and  121  act as a heat exchanger. In other words, the radiator  53  and the refrigerant heat exchangers  121  and  121 , which are shown in FIG. 7, function similarly to the outdoor heat exchanger apparatus  31  and the radiator  53 , which are shown in FIG.  1 . 
     The outside air passes through the outdoor heat exchanger apparatus  31 A and then passes through the radiator  53 , and the interval  101  is between the outdoor heat exchanger apparatus  31 A and the radiator  53 ; therefore, the outdoor heat exchanger apparatus  31 A is not effected by adverse effects of the waste heat radiated from the radiator  53 . 
     During the heating operation, the valve  122  is opened, and thereby the cooling water for the gas engine  41  passes through the radiator  53  and the warm water heat exchanger  120 . The refrigerant heat exchangers  121  and  121  are heated by the cooling water at a high temperature, which passes through the warm water heat exchanger  120 . Therefore, even when the temperature of the outdoor air is low, the refrigerant can absorb heat sufficient for evaporation from the waste heat of the cooling water for the gas engine  41 . 
     Moreover, the valve  122  is operated in response to the heating operation or the cooling operation, as explained above. However, the valve  122  may be operated in response to whether or not the refrigerant heat exchangers  121  and  121  are frosted. That is, the valve  122  can be operated depending on the temperature of the outside air, the temperature of the outdoor heat exchanger apparatus  31 A, etc. 
     Furthermore, this embodiment adopted the outdoor heat exchanger apparatus  31 A comprising three heat exchangers, but the outdoor heat exchanger apparatus  31 A is not restricted to three heat exchangers.