KR100308093B1 - Air conditioner - Google Patents

Abstract

The present invention relates to an air conditioner, wherein a refrigerant pipe from a compressor (1) is connected to an indoor heat exchanger (3) via a four-way valve (2), and a refrigerant pipe from the indoor heat exchanger (3) After passing through the expansion valve (4), branched in two directions, one is connected to the petroleum refrigerant heater (7) via the two-way valve (5), the other is the outdoor heat exchange via the two-way valve (6) To the compressor 8, the refrigerant pipe from the petroleum refrigerant heater 7 is connected to the compressor 1, and the refrigerant pipe from the outdoor heat exchanger 8 is a four-way valve 2 and a non-return valve 9 By returning to the compressor 1 via), the operation control unit 10 switches the heat pump operation and the refrigerant heating operation according to the outside temperature signal from the outside temperature sensor 11 to execute the control.

The present invention provides an air conditioner that switches between operation of a heat pump operation using an air heat source and a refrigerant heating operation using a combustion heat source in consideration of economy and comfort, while reducing heating operation costs and improving comfort. do.

Description

Air Conditioning Equipment {AIR CONDITIONER}

The present invention relates to an air conditioner having a refrigerant heater for heating a refrigerant during heating.

In recent years, the air conditioner market mainly based on heat pumps has released a number of models that have further energy saving and high heating.

In terms of energy saving, efforts have been made to improve the performance of compressors, blowers, heat exchangers and the like to reduce the difference between the evaporation temperature and the condensation temperature and to lower the input of the refrigeration cycle.

In high heating, it is possible to exhibit high heating capability even at low ambient temperature due to the use of heat storage, the use of liquid injection, and the improvement of compressor input efficiency.

On the other hand, in a cold district in which the outdoor air temperature is lowered in winter, a refrigerant heating air conditioner that heats and evaporates a refrigerant with a combustion heat source such as petroleum or gas has been introduced to the market.

However, as long as the heat pump type is used to spread the air heat source, the evaporation temperature of the refrigerant must be less than or equal to the outside air temperature, and when the outside air temperature is low, it adheres to frost (hereinafter, referred to as "wearing"), Another problem remains, such as a decrease in the heating capacity due to a decrease in the refrigerant circulation amount.

Refrigerant heating is generally a device that circulates a refrigerant evaporated by heating using a compressor. Since the input of the compressor as a gas pump is relatively high, high heating capability can be exhibited, but the maintenance cost is never cheap. In particular, in the refrigerant heating method by gas combustion, gas cost is high and electricity cost is also required. Therefore, the refrigerant heating method using petroleum as fuel instead of gas can reduce the maintenance cost relatively.

On the other hand, under the condition where the outside air temperature is high, the heat pump type can exhibit sufficient heating capacity and the heating cost is lower than that of the refrigerant heating method by gas or petroleum fuel.

The present invention takes advantage of the characteristics of the refrigerant heating by the heat pump and the combustion heat source, and in the heating cycle, the heat pump operation by the air heat source and the refrigerant heating operation by the combustion heat source are switched in consideration of economy and comfort, and during heating. It is an object of the present invention to provide an air conditioner which reduces operating costs and improves comfort.

1 is a configuration diagram showing a first embodiment related to an air conditioner of the present invention;

2 is a view showing an example of a heating operation cost with respect to the outside temperature;

3 is a view showing the switching temperature of operation at the time of rising and falling of the outside air temperature,

4 is a configuration diagram showing a second embodiment related to the air conditioner of the present invention;

5 is an operation explanatory diagram showing a third embodiment related to the air conditioner of the present invention;

6 is an explanatory diagram for switching the operation when the heating capacity is raised and lowered;

7 is a configuration diagram showing a fourth embodiment related to the air conditioner of the present invention;

8 is an explanatory diagram showing a heating ratio and a CO ₂ reduction rate of a hybrid operation compared with a conventional propane gas refrigerant heating operation,

9 is an explanatory diagram showing a switching temperature of operation at the time of rising and falling of the outside air temperature;

10 is a configuration diagram showing a modification of the fourth embodiment related to the air conditioner of the present invention;

11 is a configuration diagram showing a fifth embodiment related to the air conditioner of the present invention.

* Explanation of symbols for main parts of the drawings

1: compressor 2: 4-way valve

3: indoor heat exchanger 4: solenoid expansion valve

5, 6, 13: Two-way valve 7: Petroleum refrigerant heater

8: outdoor heat exchanger 9: non-return valve

10: operation control unit 11: outside temperature sensor

12: capillary tube 14, 15: three-way valve

17: gas refrigerant heater

In order to solve the above problems, the air conditioner of the present invention includes a refrigerant heater that heats a refrigerant as a combustion heat source, an outdoor heat exchanger that performs heat exchange between the refrigerant and outdoor air, and performs heat exchange between the refrigerant and indoor air. From an indoor heat exchanger, a compressor for circulating a refrigerant, a switching valve for switching a refrigerant circulation path to either the outdoor heat exchanger or the refrigerant heater, an outside air temperature sensor for detecting the outside air temperature, and the outside air temperature sensor And an operation control means for switching the switching valve according to the outside temperature signal to switch between the heat pump operation and the refrigerant heating operation.

With the above configuration, the heat pump operation and the refrigerant heating operation are switched in accordance with the outside air temperature signal from the outside air temperature sensor, thereby realizing high heating capability at low outside air temperature and reducing the running cost during heating.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail with reference to drawings.

1 is a configuration diagram showing a first embodiment related to the air conditioner of the present invention. Here, the connection by the solid line indicates the flow of the refrigerant, and the connection by the broken line indicates the flow of the control signal. The refrigerant pipe from the compressor 1 is connected to the indoor heat exchanger 3 via the four-way valve 2. The refrigerant piping from the indoor heat exchanger (3) passes through the electromagnetic expansion valve (4), branches in two directions, and one side passes through the two-way valve (5) (first opening / closing valve). Is connected to the outdoor heat exchanger 8 via the two-way valve 6 (second open / close valve). The refrigerant piping from the petroleum refrigerant heater (7) is connected to the compressor (1), and the refrigerant piping from the outdoor heat exchanger (8) is connected to the compressor (1) via a four-way valve (2) and a non-return valve (9). Return to In addition, a capillary tube 12 and a two-way valve 13 are connected between the two-way valve 6 and the compressor 1. The driving controller 10 executes the driving control according to the outside air temperature signal from the outside air temperature sensor 11.

Next, the operation control operation of the operation control unit 10 will be described. After starting the device, when the temperature of the combustion vaporizer of the petroleum refrigerant heater 7 reaches the set temperature by heater preheating, the refrigerant recovery operation is started. Refrigerant recovery sets the four-way valve (2) so that the refrigerant flows in the direction of the solid arrow, closes the two-way valve (5, 6) to operate the compressor (1), the petroleum refrigerant heater (7) and outdoor The refrigerant stored in the heat exchanger (8) is recovered during the indoor heat exchanger (3) and piping. When the refrigerant recovery is completed, the two-way valve 5 is opened to ignite kerosene as a fuel to start heating operation by petroleum refrigerant heating. An electronic expansion valve is used to detect the temperature of the inlet and outlet of the petroleum refrigerant heater 7 (or the suction temperature of the compressor 1) with a sensor and to ensure that the superheat of the refrigerant evaporated in the petroleum refrigerant heater 7 is constant. In 4) the flow of the refrigerant is controlled.

Figure 2 shows an example of the heating operation cost with respect to the outside temperature of the petroleum refrigerant heating alone operation and heat pump alone operation using conventional kerosene in any cold land. In this case, the annual total heating cost can be obtained by integrating the heating cost for each outside air temperature of 1 ° C, about 50,000 yen for petroleum refrigerant heating alone, and about 54,000 yen for heat pump alone.

The annual heating cost depends on the outside temperature, its duration, building load, and performance of the heat pump and refrigerant heater in the cold area. Therefore, it is necessary to calculate the heating operation cost in consideration of the newly installed place and the performance of the equipment in order to improve the accuracy of the heating cost calculation. Do. The method of calculating the heating operation cost may be, for example, a method based on JIS C 9612 or a calculation method in consideration of an officially recognized air conditioning load. The method of using the heating performance test result of changing the ambient temperature to improve the accuracy of the equipment performance I think it is better than this.

In the case of the example of Fig. 2, since the heating capacity depends on the outside temperature of the heat pump operation, the heating cost is lower for the heat pump operation when the outside temperature is 1 ° C or higher and the refrigerant heating operation when it is lower than 1 ° C. Therefore, in order to minimize the maintenance cost, running a hybrid operation for switching the heat pump operation and the refrigerant heating operation at 1 ° C. can reduce the running cost. However, in the heat pump operation, defrosting operation is considered when the comfort of heating is taken into consideration because defrosting (hereinafter referred to as defrosting) operation is started because the outdoor heat exchanger starts to form when the outside temperature is around 5 ° C. It is preferable to avoid as much as possible the rest of the heating operation between the two. Therefore, in the hybrid operation, in consideration of heating comfort, the switching temperature is set slightly higher than 1 ° C., thereby eliminating the rest of the heating, and reducing the operation cost to some extent.

Therefore, in the first embodiment, considering that the actual frosting temperature is about 5 DEG C in the heat pump operation, as shown in Fig. 3, the refrigerant heating operation is executed when the outside air temperature is low when the operation is started. When the outside temperature rises to 7 ° C, it switches to heat pump operation. When the outside temperature is 7 ° C or higher, the heat pump operation is continued. When the outside temperature drops to 5 ° C or lower, the operation is switched to the refrigerant heating operation. The control stability and comfort can be improved by changing the switching temperature of the operation when the outside temperature rises and falls.

The air conditioner of the first embodiment of the present invention shown in Fig. 1 starts the refrigerant heating operation in preference to the external air temperature at the start of the heating operation. At this time, when the outside air temperature indicated by the outside air temperature sensor 11 is 7 ° C. or less, the refrigerant heating operation is continued as it is. On the other hand, when starting the heating operation, if the outside air temperature has already exceeded 7 ° C, the refrigerant is switched from the heating operation to the heat pump operation after a certain time from the start. The operation switching is continued while the compressor 1 continues, and after the combustion of the petroleum refrigerant heater 7 is stopped, the two-way valve 5 is closed and the two-way valve 6 is opened to cool the flow of the refrigerant. Switch to (8). The electronic expansion valve 4 detects the temperature of the inlet and the outlet of the outdoor heat exchanger 8 (or the suction temperature of the compressor 1) with a sensor, and the superheat degree of the refrigerant evaporated in the outdoor heat exchanger 8 is constant. To control the flow rate of the refrigerant.

When the heat exchanger detects the frost of the outdoor heat exchanger 8 with a frost detector (not shown) during operation of the heat pump, the two-way valve 13 is opened and the high temperature compressor discharge gas is returned to the inlet of the outdoor heat exchanger 8 to defrost. Carry out the operation.

When the outside air temperature drops to 5 ° C or less, the operation is switched from the heat pump operation to the refrigerant heating operation. The operation switching is almost the same as the control at the start. That is, while the compressor 1 is in operation, the two-way valve 5 and the two-way valve 6 are closed, and the refrigerant contained in the petroleum refrigerant heater 7 and the outdoor heat exchanger 8 is transferred to the indoor heat exchanger 3 and the piping. Collect on the way. The combustion vaporizer of the petroleum refrigerant heater 7 starts preheating by the heater at the same time as or before the start of the refrigerant recovery in consideration of the preheating time.

When the refrigerant recovery is completed, the two-way valve 5 is opened. After the completion of the refrigerant recovery, when the temperature of the combustion vaporizer in the petroleum refrigerant heater 7 reaches the set temperature, ignition of kerosene as fuel is performed to start the heating operation by petroleum refrigerant heating. The temperature of the inlet and the outlet of the petroleum refrigerant heater 7 is detected by a sensor, and the flow rate of the refrigerant is controlled by the expansion valve 4 so that the superheat degree of the refrigerant evaporated in the petroleum refrigerant heater 7 is constant.

The difference between the operation switching to the refrigerant heating in this heat pump compared with the refrigerant heating operation at startup is that the blower of the indoor unit rotates in accordance with the temperature of the indoor heat exchanger to continue heating operation even when the former is recovering the refrigerant.

In the first embodiment, the refrigerant heating operation is executed at the time of heating start, but the heat pump operation is executed when the oil residual amount detector (not shown) detects that the residual oil amount is low. When the petroleum refrigerant heater 7 is broken and it is difficult to execute the refrigerant heating operation, the heat pump operation is forcibly executed as an emergency evacuation operation. The forced driving instruction is executed by operating a remote controller or a switch included in the indoor unit. When defrosting the outdoor heat exchanger 8 at low ambient temperature and high humidity, the defrosting operation is performed by opening the two-way valve 13 and returning the high-temperature compressor discharge gas to the inlet of the outdoor heat exchanger 8 to perform the defrosting operation. Run

The defrosting operation may be changed to a configuration in which the four-way valve 2 is inverted to return the high temperature compressor discharge gas to the outdoor heat exchanger 8. In this case, since the capillary tube 12 shown in FIG. 1, the two-way valve 13, and the piping which connects them can be eliminated, the structure of a cycle can be simplified and cost can be reduced.

4 is a configuration diagram showing a second embodiment related to the air conditioner of the present invention. Here, the connection by the solid line indicates the flow of the refrigerant, and the connection by the broken line indicates the flow of the control signal. The refrigerant pipe from the compressor 1 is connected to the indoor heat exchanger 3 via the four-way valve 2. The refrigerant pipe from the indoor heat exchanger (3) is connected to the three-way valve (14) after passing through the electromagnetic expansion valve (4), and one side of the refrigerant pipe branched from the three-way valve (14) is a petroleum refrigerant heater. It is connected to (7), and the other is connected to the outdoor heat exchanger (8). The refrigerant pipe from the petroleum refrigerant heater 7 is connected to the three-way valve 15, and the refrigerant pipe branched from the three-way valve 15 has one side connected to the compressor 1, and the other side the three-way valve. It is connected to the outdoor heat exchanger 8 with the piping from (14). The refrigerant pipe from the outdoor heat exchanger 8 is returned to the compressor 1 via the four-way valve 2 and the non-return valve 9. The driving control unit 10 executes driving control in accordance with the outside air temperature signal from the outside air temperature sensor 11.

Next, the operation control operation of the operation control unit 10 will be described. After starting the device, first, the four-way valve 2 is set so that the refrigerant flows in the refrigerant pipe in the direction of the solid arrow, and the refrigerant flows from the three-way valve 14 to the petroleum refrigerant heater 7 from the electromagnetic expansion valve 4. The three-way valve 15 is set such that the refrigerant flows from the petroleum refrigerant heater 7 to the outdoor heat exchanger 8. And the combustion vaporizer of the petroleum refrigerant heater 7 starts preheating by a heater. When the temperature of the combustion vaporizer of the petroleum refrigerant heater 7 reaches the set temperature, the compressor 1 is operated to perform ignition of kerosene, which is a fuel, to start heating operation by petroleum refrigerant heating. The temperature of the inlet and the outlet of the petroleum refrigerant heater 7 is detected by a sensor, and the flow of the refrigerant is controlled by the electromagnetic expansion valve 4 so that the superheat degree of the refrigerant evaporated in the petroleum refrigerant heater 7 is constant. After a certain time of starting the superheat degree control, the three-way valve 15 is switched to change the flow of the refrigerant from the petroleum refrigerant heater 7 to the compressor 1, and the outdoor heat exchanger 8 is closed. In this manner, the second embodiment does not require the refrigerant recovery operation at startup.

In the air conditioner according to the second embodiment, when the heating operation is started, the refrigerant heating operation is started with priority regardless of the outside air temperature. At this time, when the outside air temperature indicated by the outside air temperature sensor 11 is 7 ° C. or less, the refrigerant heating operation is continued as it is. On the other hand, when the heating operation is started, when the outside air temperature has already exceeded 7 ° C, the refrigerant is switched from the heating operation to the heat pump operation after a certain time from the start. In the operation switching, after the combustion of the petroleum refrigerant heater 7 is stopped while the operation of the compressor 1 is continued, the three-way valve 14 is switched to close the petroleum refrigerant heater 7 and the electromagnetic expansion valve ( The refrigerant flows from 4) to the outdoor heat exchanger (8). The temperature of the inlet and the outlet of the outdoor heat exchanger 8 is detected by a sensor, and the flow rate of the refrigerant is controlled by the expansion valve 4 so that the superheat degree of the refrigerant evaporated in the outdoor heat exchanger 8 is constant.

When the detection of the outdoor heat exchanger 8 is detected by a frost detector (not shown) during the operation of the heat pump, the three-way valve 14 is switched and the refrigerant from the electromagnetic expansion valve 4 toward the petroleum refrigerant heater 7 is detected. Flow and run petroleum combustion. At the same time, the three-way valve 15 is set to flow from the petroleum refrigerant heater 7 to the outdoor heat exchanger 8. The hot refrigerant heated by the petroleum refrigerant heater 7 and evaporated is sucked into the compressor 1 while performing defrost through the outdoor heat exchanger 8 that has been implanted. The solenoid expansion valve 4 is controlled by detecting the temperature of the inlet and outlet of the petroleum refrigerant heater 7 with a sensor so that the superheat degree of the refrigerant evaporated in the petroleum refrigerant heater 7 is constant. Since the liquid bag amount of the refrigerant at the inlet is made as small as possible, the superheat set temperature becomes larger than in the case of normal refrigerant heating operation. A feature of this defrosting operation is that continuous heating operation can be performed while performing defrosting operation. When the defrost is finished, the three-way valves 14 and 15 are switched to return to normal heat pump operation.

When the outside air temperature drops to 5 ° C or less, the operation is switched from the heat pump operation to the refrigerant heating operation. The operation switching is almost the same as the control at the start. That is, the three-way valve 14 is switched so that the refrigerant flows from the electromagnetic expansion valve 4 toward the petroleum refrigerant heater 7, and the three-way valve 15 is switched from the petroleum refrigerant heater 7 to the outdoor heat exchanger 8. Switch to flow refrigerant

The combustion vaporizer of the petroleum refrigerant heater 7 starts preheating by the heater so as to be preheated off before switching from the heat pump operation to the refrigerant heating operation. When the switching of the refrigerant circuit is completed and the temperature of the combustion vaporizer of the petroleum refrigerant heater 7 reaches the set temperature, ignition of kerosene as fuel is executed to start the heating operation by petroleum refrigerant heating. The temperature of the inlet and the outlet of the petroleum refrigerant heater 7 is detected by a sensor, and the flow of the refrigerant is controlled by the electromagnetic expansion valve 4 so that the superheat degree of the refrigerant evaporated in the petroleum refrigerant heater 7 is constant. After a certain time of starting the superheat degree control, the three-way valve 15 is switched to change the flow of the refrigerant from the petroleum refrigerant heater 7 to the compressor 1, and the outdoor heat exchanger 8 is closed. Thus, in this embodiment, the refrigerant recovery operation at the time of operation switching is not required. For this reason, the fall of a heating capability is very small and comfort can be improved.

In the second embodiment, the refrigerant heating operation is executed at the time of heating start, but the heat pump operation is executed when the oil residual amount detector (not shown) detects that the oil residual amount is small. When the petroleum refrigerant heater 7 is broken and it is difficult to execute the refrigerant heating operation, the heat pump operation is forcibly executed as an emergency evacuation operation. In this case, the three-way valve 14 is switched to close the oil refrigerant heater 7 side, and the refrigerant flows from the electromagnetic expansion valve 4 to the outdoor heat exchanger 8 side. At the same time, the three-way valve 15 is switched to close between the petroleum refrigerant heater 7 and the outdoor heat exchanger 8. The temperature of the inlet and the outlet of the outdoor heat exchanger 8 is detected by a sensor, and the flow rate of the refrigerant is controlled by the electromagnetic expansion valve 4 so that the superheat degree of the refrigerant evaporated in the outdoor heat exchanger 8 is constant.

The forced driving instruction is executed by operating a switch provided in the remote controller or the indoor unit. When defrosting the outdoor heat exchanger (8) at low ambient temperature and high humidity, the defrosting operation inverts the four-way valve (2) to return high-temperature compressor discharge gas to the inlet of the outdoor heat exchanger (8). Run

Next, a third embodiment will be described.

The third embodiment is characterized in that the operation is controlled by selecting either the heat pump operation or the refrigerant heating operation according to not only the outside temperature but also the heating capability required for air conditioning. In addition, in this 3rd Example, since the cycle structure is the same as that shown in FIG. 1, description of the structure is abbreviate | omitted and the operation | movement is demonstrated using FIG.

Fig. 5 is a horizontal axis indicating an outside air temperature (° C) and a vertical axis indicating heating capacity required for air conditioning, and operation control is performed by selecting either a heat pump operation or a refrigerant heating operation according to the outside temperature and the heating capacity. It is explanatory drawing which shows to do.

The air conditioner of the third embodiment starts at the start of the heating operation in preference to the refrigerant heating operation regardless of the outside temperature. At this time, for example, when it is determined that the heating capacity required for air conditioning is the maximum Qmax when the outside air temperature is 4 ° C, the heating capacity is larger than Q1 as shown in FIG. Coolant heating operation is performed. The heating capacity required for air conditioning is calculated based on the difference between the room temperature detected in the room and the set temperature. In other words, when the difference between the room temperature and the set temperature is large, the required heating capacity is set high. Here, to obtain the heating capacity (Qmax) is carried out by controlling the amount of oil burned.

After the refrigerant heating operation is continued while the outside temperature is 4 ° C., the temperature of the room rises, and the required heating capacity gradually decreases. When the temperature is lower than Q1, the operation is switched to the heat pump operation. At this time, the heating capability in the heat pump operation is performed by controlling the rotation speed of the compressor 1 by the control frequency of an inverter power source (not shown) connected to the compressor 1. Then, if the door of the room is opened while the heat pump operation continues, and the room temperature drops sharply and the heating capacity requiring air conditioning exceeds Q2, the operation is switched back to the refrigerant heating operation to execute the operation control.

When the heating operation is started and the refrigerant heating operation is started, when the outside temperature is 4 ° C, the temperature detected in the room is close to the set temperature, the heating capacity required for air conditioning is low, and the heating capacity required is If it is smaller than Q1, it is controlled to switch to heat pump operation after a certain time.

On the other hand, in the case of heating operation, when the outside temperature falls from 4 ° C. and falls below −1 ° C., as shown in FIG. 5, the operation is switched to the refrigerant heating operation to control the operation. Controls operation by switching to heat pump operation.

Here, the switching of the heat pump operation and the refrigerant heating operation according to the heating capacity required is a variable width of about 0.7 to 6.0 kW in the heat pump operation, a variable width of about 2.5 to 6.6 kW in the refrigerant heating operation, and a heat pump. The operating range has a wide range in which the heating capacity can be varied, and in particular, in the low heating capacity region, selecting a wide variable heat pump operation improves the operating efficiency and improves the comfort of heating.

By the way, in the third embodiment, as shown in Fig. 6, when the heating capacity required for air conditioning (hereinafter referred to as the required capability) is low and the Q1 is less than Q1, the heat pump operation is executed. After that, when the required capacity rises and Q2 is exceeded, the operation is switched from the heat pump operation to the refrigerant heating operation. After the refrigerant heating operation is started, the heat pump operation is prevented from entering until the required capacity is below Q1. Therefore, since the switching capability of driving is changed when the required capability rises and falls, the stability of control and comfort can be improved.

In this way, the operation is controlled by switching the heat pump operation and the refrigerant heating operation in accordance with not only the outside temperature but also the heating capacity required for air conditioning, thereby improving comfort while reducing the heating operation cost.

In addition, in the third embodiment, as shown in Fig. 5, three types of switching points of the outside air temperature or the heating capacity are set, respectively, and in particular, the outdoor heat exchanger tends to form a low temperature, and the outside air temperature at which the efficiency of the heat pump operation is low is low. Since the area is set so as to increase the ratio of the refrigerant heating operation, fine room temperature control can be executed, and the comfort of heating can be greatly improved.

7 is a configuration diagram showing a fourth embodiment related to the air conditioner of the present invention. Here, the connection by the solid line indicates the flow of the refrigerant, and the connection by the broken line indicates the flow of control signals by the operation control unit, which is an operation control means described later. The refrigerant pipe from the compressor (1) is connected to the indoor heat exchanger (3) via a four-way valve (2). The refrigerant pipe from the indoor heat exchanger (3) passes through an electronic expansion valve (4), and Branched in two directions, one side is connected to the gas refrigerant heater 17 via the two-way valve 5 (first open / close valve), and the other is via the two-way valve 6 (second open / close valve). Is connected to the outdoor heat exchanger (8). The refrigerant piping from the gas refrigerant heater (17) is connected to the compressor (1), and the refrigerant piping from the outdoor heat exchanger (8) is connected to the compressor (1) via a four-way valve (2) and a non-return valve (9). Return to The capillary tube 12 and the two-way valve 13 are connected between the upstream side of the two-way valve 6 and the discharge side of the compressor 1. The driving control unit 10 serving as the driving control unit executes the driving control in accordance with the signals from the outside temperature sensor 11 and the heating capability request mode switch S1.

Next, the operation control operation of the operation control unit 10 will be described. In the heating operation mode, when the hybrid operation for performing the heat pump operation and the gas refrigerant heating operation is selected, the refrigerant recovery operation is started after the device is started. In the refrigerant recovery, the four-way valve (2) is set so that the refrigerant flows in the direction of the solid arrow, the two-way valves (5 and 6) are closed, and the compressor (1) is operated to exchange the gas refrigerant heater (17) and the outdoor heat exchange. The refrigerant stored in the machine 8 is recovered during the indoor heat exchanger 3 and the piping. When the refrigerant recovery is completed, the two-way valve 5 is opened to ignite the gas as a fuel, and heating operation by gas refrigerant heating is started. The temperature of the inlet and the outlet of the gas refrigerant heater 17 (or the suction temperature of the compressor 1) is detected by a sensor (not shown), and the superheat degree of the refrigerant evaporated in the gas refrigerant heater 17 becomes constant. The flow of the refrigerant is controlled by the electromagnetic expansion valve (4).

Next, in this fourth embodiment, the operation control in which the heat pump operation or the refrigerant heating operation is selected in accordance with the ambient temperature and the heating capacity will be described. The basic operation selection is heat pump operation when the outside temperature is high and the demand is low, and refrigerant heating operation when the outside temperature is low and the demand is high. That is, the heat pump operation or the refrigerant heating operation is automatically selected and executed according to the heating capacity and the outside temperature.

Based on this operation control specification, for example, the heating cost and the CO ₂ reduction rate when operating with propane in gas fuel are shown in comparison with the conventional propane gas operation alone. . The calculation method is calculated by assuming that the heating equipment and installation place of our heating rating capacity 6 난방 class are applied by applying the air conditioning load calculation code LESCOM80. The places to be calculated are Tokyo and Sapporo, and the housing specifications are represented by heat loss coefficients, and the heating operation costs and the reduction rates of CO ₂ emissions when the room temperature of 12 bedroom tatami sheets are set to 20 to 27 ° C are shown. As shown in FIG. 8, the hybrid operation that performs the combination of the heat pump operation using the outdoor air heat source and the propane gas refrigerant heating operation reduces the heating cost by 30 to 65% compared to the conventional refrigerant operation of propane alone, and reduces CO ₂ emissions. Is reduced by 31 to 59%. As such, hybrid operation is excellent in protecting the global environment by suppressing warming because heating costs are low and CO ₂ emissions are reduced.

In addition, the heating operation control specification may be simplified and the heat pump operation and the gas refrigerant heating operation may be switched and operated only at the outside temperature as shown in FIG. 9. In Fig. 9, considering that the actual frosting temperature in the heat pump operation is about 5 DEG C, the gas refrigerant heating operation is executed when the outside air temperature is low at the time of starting the heating operation. Switch to heat pump operation. When the outside temperature is 7 ° C or higher, the heat pump operation is continued, and when the outside temperature drops to 5 ° C or lower, the gas coolant heating operation is switched. The control stability and comfort can be improved by changing the switching temperature of the operation when the outside temperature rises and falls.

An operation method for switching the heat pump operation and the gas refrigerant heating operation to two variable values of the outside air temperature and the heating capacity as shown in FIG. 5, or switching the heat pump operation and the gas refrigerant heating operation only with the outside temperature as shown in FIG. 9. driving method both of the reduction ratio and the reduction ratio of CO ₂ emissions by hybrid heating operation for the gas refrigerant heating single operation, as shown in Figure 8 is different from the kind of gaseous fuel varies. Therefore, although the type of gas is not shown, it can be set so as to increase the reduction rate of these by inputting and controlling the indoor remote controller, the panel unit of the indoor unit, or the outdoor unit.

In the air conditioner of the fourth embodiment shown in Fig. 7, the gas refrigerant heating operation is started in priority when the hybrid vehicle is selected as the heating operation mode regardless of the outside temperature. At this time, when the outside air temperature indicated by the outside air temperature sensor 11 is 7 ° C. or less, the gas refrigerant heating operation is continued as it is. On the other hand, when the heating operation is started, when the outside air temperature has already exceeded 7 ° C, the refrigerant is switched from the heating operation to the heat pump operation after a certain time from the start. In operation switching, after the combustion of the gas refrigerant heater 17 is stopped while the operation of the compressor 1 is continued, the two-way valve 5 is closed and the two-way valve 6 is opened to exchange the flow of refrigerant to the outdoor heat exchange. Switch to step (8). The temperature of the inlet and the outlet of the outdoor heat exchanger 8 (or the suction temperature of the compressor 1) is detected by a sensor (not shown), and the superheat degree of the refrigerant evaporated in the outdoor heat exchanger 8 becomes constant. The amount of shrinkage of the refrigerant is controlled by the electromagnetic expansion valve (4).

When a heat detector operates to detect an idea of the outdoor heat exchanger 8 when the heat pump is operated, the two-way valve 13 is opened to return the high-temperature compressor discharge gas to the inlet of the outdoor heat exchanger 8 to defrost it. Carry out the operation.

When the outside air temperature drops to 5 ° C. or less, the operation is switched from the heat pump operation to the gas refrigerant heating operation. Operation switching is almost the same as control at start. That is, the refrigerant stored in the gas refrigerant heater 17 and the outdoor heat exchanger 8 while the compressor 1 is closed while the two-way valve 5 and the two-way valve 6 are closed while the compressor 1 is in operation. Is collected during the indoor heat exchanger (3) and piping. When the refrigerant recovery is completed, the two-way valve 5 is opened. After completion of the refrigerant recovery, ignition of the gas serving as fuel is performed to start the heating operation by gas refrigerant heating. The electronic expansion valve (1) detects the temperature of the inlet and the outlet of the gas refrigerant heater 17 (or the suction temperature of the compressor 1) with a sensor and makes the superheat degree of the refrigerant evaporated in the gas refrigerant heater 17 constant. 4) to control the flow rate of the refrigerant.

The difference between the operation switching of the gas refrigerant heating furnace and the gas refrigerant heating operation at the start of the heat pump is different from that of the gas refrigerant heating operation at the start. It is. However, when the indoor heat exchanger temperature drops to a predetermined temperature or less, the blower 16 of the indoor unit does not rotate.

In the fourth embodiment, when the hybrid operation is selected as the heating operation mode, the gas refrigerant heating operation is executed at the time of heating start, but the gas residual amount detector (not shown, including the flame detector) decreases or disappears. Is detected, the heat pump operation is executed. In addition, when it is difficult to execute the refrigerant heating operation due to lack of fuel and failure of the gas refrigerant heater 17, the heat pump operation can be selected. In addition, when the heat pump operation is difficult due to frost, snow, ice, or the like adhering to the outdoor heat exchanger 8 or when a sufficient heating feeling cannot be obtained by the heat pump operation, the gas refrigerant heating operation can be selected. That is, the heating operation selection mode includes three operation modes of hybrid operation, heat pump operation, gas refrigerant heating operation, and the user may select one of the indoor licomon setting, the indoor unit panel setting, or the outdoor unit setting. Heating operation can be selected and operated.

In the hybrid operation, the type of gas can be inputted by any one of the above three setting operations to select an operation control specification changed to a more suitable outside temperature and a switching point of heating capacity.

In addition, defrosting when the outdoor heat exchanger 8 is formed at low outdoor air temperature and high humidity causes defrosting by opening the two-way valve 13 to return the high-temperature compressor discharge gas to the inlet of the outdoor heat exchanger 8. Run

The defrosting operation may be changed to a configuration in which the flow path of the four-way valve 2 is reversed to return the high temperature compressor discharge gas to the outdoor heat exchanger 8 as in the refrigerating cycle shown in FIG. 10. In this case, the capillary tube 12, the two-way valve 13, and the pipe connecting the same can be eliminated, so that the cycle configuration can be simplified and the cost can be reduced.

11 is a configuration diagram showing a fifth embodiment related to the air conditioner of the present invention. Here, the connection by the solid line indicates the flow of the refrigerant, and the connection by the broken line indicates the flow of the control signal by the operation control unit 10. The refrigerant pipe from the compressor 1 is connected to the indoor heat exchanger 3 via the four-way valve 2. The refrigerant pipe from the indoor heat exchanger (3) is connected to the three-way valve (14) via the electromagnetic expansion valve (4), and the refrigerant pipe branched from the three-way valve (14) is a gas refrigerant heater. (17), and the other is connected to the outdoor heat exchanger (8). The refrigerant pipe from the gas refrigerant heater 17 is connected to the three-way valve 15, and the refrigerant pipe branched from the three-way valve 15 has one side connected to the compressor 1 and the other side the three-way valve. It is connected to the outdoor heat exchanger 8 with the piping from (14). The refrigerant pipe from the outdoor heat exchanger 8 is returned to the compressor 1 via the four-way valve 2 and the non-return valve 9. The operation control unit 10 executes the outside air temperature sensor 11 and the heating capacity in accordance with the outside air temperature signal at the required mode switch S1. Instead of the three-way valve 14 and the three-way valve 15, two two-way valves having such a movement may be substituted for four in total.

Next, the operation control operation of the operation control unit 10 will be described. After starting the device, first, the four-way valve 2 is set so that the refrigerant flows in the refrigerant pipe in the direction of the solid arrow, and the refrigerant flows from the three-way valve 14 to the gas refrigerant heater 17 from the electromagnetic expansion valve 4. The three-way valve 15 is set such that the refrigerant flows from the gas refrigerant heater 17 to the outdoor heat exchanger 8. A hybrid operation as a selection mode of heating operation is selected by an indoor remote controller (not shown), and when an operation command is issued, the compressor 1 is driven, and ignition of gas as fuel is performed to start heating operation by gas refrigerant heating. . The temperature of the inlet and the outlet of the gas refrigerant heater 17 (or the suction temperature of the compressor 1) is detected by a sensor (not shown), and the superheat degree of the refrigerant evaporated in the gas refrigerant heater 17 becomes constant. The flow rate of the refrigerant is controlled by the electromagnetic expansion valve (4). After a certain time of starting the superheat degree control, the three-way valve 15 is switched to change the flow from the gas refrigerant heater 17 to the compressor 1 to close the outdoor heat exchanger 8. In this manner, this fifth embodiment does not require the refrigerant recovery operation at startup.

In the air conditioner of the fifth embodiment, at the start of heating operation, the refrigerant heating operation is started with priority regardless of the outside temperature. At this time, as shown in FIG. 9, when the outside temperature shown by the outside temperature sensor 11 is 7 degrees C or less, refrigerant heating operation is continued as it is. On the other hand, when the heating operation is started, when the outside air temperature has already exceeded 7 ° C., the refrigerant is switched from the heating operation to the heat pump operation after a certain time from the start. In the operation switching, after the combustion of the gas refrigerant heater 17 is stopped while the operation of the compressor 1 is continued, the three-way valve 14 is switched to close the gas refrigerant heater 17, and the solenoid control valve 4 ) To the outdoor heat exchanger (8). The temperature of the inlet and the outlet of the outdoor heat exchanger 8 (or the suction temperature of the compressor 1) is detected by a sensor (not shown), and the superheat degree of the refrigerant evaporated in the outdoor heat exchanger 8 becomes constant. The amount of shrinkage of the refrigerant is controlled by the electromagnetic expansion valve (4).

When the heat detector operates to detect the frost of the outdoor heat exchanger 8 with a frost detector (not shown), the three-way valve 14 is switched to transfer the refrigerant from the electromagnetic expansion valve 4 toward the gas refrigerant heater 17. Flow, and gas combustion is performed. At the same time, the flow path of the three-way valve 15 is switched to set the refrigerant to flow from the gas refrigerant heater 7 to the outdoor heat exchanger 8. The hot refrigerant heated by the gas refrigerant heater 17 and evaporated is sucked into the compressor 1 while performing defrost through the outdoor heat exchanger 8 that has been implanted. The electromagnetic expansion valve 4 detects the temperature of the inlet and the outlet of the gas refrigerant heater 17 (or the suction temperature of the compressor 1) by the sensor so that the superheat degree of the refrigerant evaporated from the gas refrigerant heater 17 is constant. In order to make the liquid bag amount of the refrigerant at the inlet of the compressor 1 as small as possible, the superheat set temperature is larger than in the case of the normal refrigerant heating operation. A feature of this defrosting operation is that continuous heating operation can be performed while performing defrosting operation. When the defrost is completed, the three-way valves 14 and 15 are switched to return to normal heat pump operation.

When the outside air temperature drops to 5 ° C or less, the operation is switched from the heat pump operation to the refrigerant heating operation. The operation switching is almost the same as the control at the start. That is, the three-way valve 14 is switched so that the refrigerant flows from the electromagnetic expansion valve 4 toward the gas refrigerant heater 17, and the three-way valve 15 is switched from the gas refrigerant heater 17 to the outdoor heat exchanger 8. Switch to flow refrigerant

When the switching of the refrigerant circuit is completed and the ignition of the gas serving as fuel is performed, heating operation by gas refrigerant heating is started. The flow of the refrigerant is controlled by the electromagnetic expansion valve 4 so that the superheat degree of the refrigerant evaporated in the gas refrigerant heater 17 is constant. After a certain time of starting the superheat degree control, the three-way valve 15 is switched to change the flow of the refrigerant from the gas refrigerant heater 17 to the compressor 1 to close the outdoor heat exchanger 8. In this manner, the fifth embodiment does not require the refrigerant recovery operation at the time of operation switching. For this reason, the fall of a heating capability is very small and comfort can be improved.

In the fifth embodiment, when the hybrid operation is selected as the heating operation mode, the refrigerant heating operation is executed at the time of heating, but the gas residual detector (not shown, including the flame detector) detects that the gas fuel is reduced or disappeared. In this case, heat pump operation is performed. In this case, the three-way valve 14 is switched to close the gas refrigerant heater 17, and the refrigerant flows from the electromagnetic expansion valve 4 to the outdoor heat exchanger 8. At the same time, the three-way valve 15 is switched to close between the gas refrigerant heater 17 and the outdoor heat exchanger 8. The electronic expansion valve 4 detects the temperature of the inlet and the outlet of the outdoor heat exchanger 8 (or the suction temperature of the compressor 1) with a sensor and makes the superheat of the refrigerant evaporated in the outdoor heat exchanger 8 constant. To control the shrinkage of the refrigerant.

In addition, heat pump operation can be selected when it is difficult to execute the refrigerant heating operation due to lack of fuel or failure of the gas refrigerant heater 17. When defrosting the outdoor heat exchanger (8) at low ambient temperature and high humidity, the defrosting operation inverts the four-way valve (2) to return high-temperature compressor discharge gas to the inlet of the outdoor heat exchanger (8). Run

In addition, when heat, operation, etc. are attached to the outdoor heat exchanger 8 due to frost, snow, ice or the like, or when a sufficient heating feeling cannot be obtained by the heat pump operation, the refrigerant heating operation can be selected. That is, the heating operation selection mode includes three operation modes of hybrid operation, heat pump operation, and refrigerant heating operation, and the user selects each heating operation by any one of indoor remote control setting, indoor unit panel setting, or outdoor unit setting (not shown). I can operate it. In the hybrid operation, the type of gas can be input by any one of the above three setting operations to select the operation control specification changed to a more suitable outside temperature and switching point of heating capacity.

As described above, the air conditioner of the present invention switches the heat pump operation and the refrigerant heating operation according to the outside temperature signal from the outside temperature sensor, thereby realizing high heating capability at low outside temperature and operating cost at heating. It can reduce and also improve comfort.

Claims (11)

A refrigerant heater for heating the refrigerant with a combustion heat source; An outdoor heat exchanger configured to perform heat exchange between the refrigerant and outdoor air; An indoor heat exchanger performing heat exchange between the refrigerant and indoor air; A compressor for circulating the refrigerant; A switching valve for switching the refrigerant circulation path to either the outdoor heat exchanger or the refrigerant heater; An outside air temperature sensor for detecting outside air temperature; And And an operation control means for switching between the heat pump operation and the refrigerant heating operation by switching the switching valve according to the outside air temperature signal from the outside air temperature sensor during the heating operation. And an outside air temperature for switching from the heat pump operation to the refrigerant heating operation is lower than an outside air temperature for switching from the refrigerant heating operation to the heat pump operation. The method of claim 1, The outdoor heat exchanger and a refrigerant heater using oil or gas as a combustion heat source for heating the refrigerant are connected in parallel, and the flow path of the refrigerant is switched to the outdoor heat exchanger by the switching valve. And the flow path of the refrigerant is switched to the refrigerant heater. The method of claim 2, The switching valve is composed of a first on-off valve for opening and closing the upstream side of the refrigerant heater and a second on-off valve for opening and closing the upstream side of the outdoor heat exchanger, When switching from the heat pump operation to the refrigerant heating operation, after closing the first and second on-off valve to recover the refrigerant to the indoor heat exchanger, the first on-off valve is opened. The method of claim 5, The switching valve is composed of a first on-off valve for opening and closing the upstream side of the refrigerant heater, and a second on-off valve for opening and closing the upstream side of the outdoor heat exchanger, When switching from the refrigerant heating operation to the heat pump operation, after the combustion stop of the refrigerant heater, the first on-off valve is closed and the second air-conditioning device is opened. The method of claim 1, Refrigerant heating operation, characterized in that the priority is given to the refrigerant heating operation regardless of the outside temperature at the start of the heating operation. The method of claim 2, And a residual amount detecting means for detecting the residual amount of oil or gas, wherein the residual amount detecting means performs a heat pump operation when detecting that the residual amount of oil or gas is low or when the refrigerant heater fails. Conditioner. The method of claim 1, The outdoor heat exchanger and the refrigerant heater are connected to each other in parallel or in series and have an idea detection means for detecting attachment of a frost to the heat exchanger. And defrosting operation is carried out by connecting the outdoor heat exchanger and the refrigerant heater in series when an idea is detected. The method of claim 10, When switching from the heat pump operation to the refrigerant heating operation, the refrigerant flows from the refrigerant heater to the outdoor heat exchanger to perform the refrigerant heating operation, and then the refrigerant flows directly from the refrigerant heater to the compressor. Conditioner. The method of claim 10, And the refrigerant flow is switched from the refrigerant heater to the outdoor heat exchanger after the combustion of the refrigerant heater is stopped when switching from the refrigerant heating operation to the heat pump operation. An air conditioner having a refrigeration cycle having an air heat source and a combustion heat source of oil or gas, And an operation control means for executing the refrigerant heating operation until an operation stop command is issued when the detection of the concept of the outdoor heat exchanger at the time of heating cycle operation. Selection control operation means for selecting one of heat pump operation using air heat source, gas refrigerant heating operation using gas combustion heat source, or hybrid operation combining heat pump operation and gas refrigerant heating operation during heating operation. And the selection control driving means is installed in any one of an indoor remote controller, a panel unit of an indoor unit, and an outdoor unit.