JP3380452B2 - Refrigeration cycle apparatus and retrofit method for refrigeration cycle apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a retrofitting method for a refrigerating cycle device for retrofitting a refrigerating cycle device using a refrigerant other than HC refrigerant, for example, R22, as a refrigerant, and a HC. The present invention relates to a refrigeration cycle device using a refrigerant.

[0002]

2. Description of the Related Art A working medium in an air conditioner using a refrigeration cycle apparatus including a compressor, a condenser, a throttle device, an evaporator, an accumulator, etc. in recent years has a harmful effect on an ozone layer. H, which is an alternative refrigerant that does not pose a threat to the ozone layer from the refrigerant or HCFC refrigerant
It is being transferred to FC and HC refrigerants.

That is, the working medium for an air conditioner is HCF.
From C refrigerant R22 (chlorodifluoromethane, CHClF _2, boiling point -40.8 ° C.), R32 of HFC refrigerant, R12
5, mixed refrigerant such as R134a and R290 of HC refrigerant
(Propane, CH ₃ -CH ₂ -CH _3, boiling point -42.1 ° C.), R1
270 (propylene, CH ₃ -CH = CH _2, boiling point -47.7 ℃)
Or, R170 (ethane, CH ₃ -CH _3, boiling point -88.8 ℃)
It has been proposed to shift to a mixed refrigerant with.

However, the HFC refrigerants R32, R125,
A mixed refrigerant such as R134a is used as a lubricant for a compressor such as mineral oil or alkylbenzene oil which has been conventionally used in R22, and HFC.
Since the refrigerant has poor compatibility, it is necessary to adopt a new synthetic oil such as ester oil or ether oil, which can be used for a new air conditioner, but retrofits an air conditioner using an existing R22. Things come with great difficulty.

On the other hand, the HC refrigerant has almost no threat to the ozone layer and global warming, and has good compatibility with lubricating oils for compressors such as mineral oil and alkylbenzene oil which have been conventionally used in R22. Since HC refrigerant has a strong flammability that R22 did not have, it is desirable to install a safety device such as a leak detector separately. However, it is not possible to study a method of retrofitting an existing air conditioner using R22. , It is very significant from the viewpoint of global environment protection.

In addition, a new air conditioner for HC refrigerant is designed and
In the case of manufacturing, it is also significant to provide an air conditioner that safely and efficiently uses HC refrigerant having strong flammability.

[0007]

H that can be substituted for R22
As a C refrigerant, R290 (propane), which has the closest boiling point
However, merely changing the refrigerant from R22 to R290 cannot sufficiently fulfill the function as an air conditioner.

For example, when retrofitting an existing R22 refrigeration cycle device, the expansion device and compressor in the refrigeration cycle device are fixed by welding or the like, and when changing the refrigerant, the expansion device or It is also difficult to replace or weld the compressor. In particular, if the throttle device is not set to an appropriate throttle opening degree, it returns to the compressor as a liquid refrigerant, or the discharge temperature rises because it is returned to the compressor due to excessive overheating. It will have a great impact on reliability.

Further, in both cases of retrofitting an existing R22 refrigeration cycle apparatus and newly designing and manufacturing a refrigeration cycle apparatus using an HC refrigerant containing R290 as a main component, the refrigerant is used in both cases. Since R290 used as has a strong flammability, it is a major problem to make the refrigeration cycle apparatus capable of reducing the risk and operating efficiently by reducing the amount of the refrigerant used as much as possible.

In view of the above problems, the present invention reduces the risk and enables efficient operation by reducing the amount of R290 used as a refrigerant in a separation type air conditioner in particular. An object of the present invention is to provide a refrigeration cycle device using an HC refrigerant containing as a main component. It is another object of the present invention to provide a retrofitting method for a refrigeration cycle apparatus that easily retrofits an existing refrigeration cycle apparatus for R22 or the like to a refrigeration cycle apparatus that uses the HC refrigerant containing R290 as a main component. is there.

[0011]

In order to solve the above-mentioned problems, the present invention according to claim 1 provides an outdoor unit having a compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, and A liquid side conduit and a gas side conduit connecting an outdoor unit and the indoor unit, a throttle device included in the outdoor unit or the indoor unit, and one of the outdoor unit or the indoor unit,
A fixed throttle member, which is installed near a connection port with the liquid-side conduit that does not include the throttle device,
The refrigeration cycle apparatus is characterized by using an HC refrigerant containing 290 (propane) as a main component.

The present invention according to claim 2 is characterized in that a dryer is provided in the liquid side conduit or near a connection port between the liquid side conduit and either the outdoor unit or the indoor unit. The refrigeration cycle apparatus according to claim 1. That is, water in the air is mixed into the refrigeration cycle device when the connection pipe is opened, and R290 (propane)
HC refrigerants such as those mentioned above are equipped with a dryer because they may react with a small amount of water to generate an icing phenomenon due to clathrate (also referred to as clathrate compound or hydrate).

In the present invention of claim 3, the HC refrigerant is R
The refrigeration cycle apparatus according to claim 1 or 2, wherein the refrigerant is 290 (propane) or R290 mixed with R1270 (propylene) and / or R170 (ethane).

According to a fourth aspect of the present invention, a four-way valve for switching between heating and cooling is provided, and the fixed throttle member is one orifice portion that functions only in one of the flow directions of the HC refrigerant.
Alternatively, the refrigeration cycle apparatus according to any one of claims 1 to 3, wherein the refrigeration cycle apparatus has two orifice portions, only one of which functions depending on a flow direction of the HC refrigerant.

According to a fifth aspect of the present invention, an outdoor unit having a compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, a liquid side pipe line connecting the outdoor unit and the indoor unit, and a gas. For the refrigeration cycle apparatus including a side pipe line and a throttle device included in the outdoor unit or the indoor unit, the refrigerant is changed to the HC refrigerant, and the fixed throttle member or the fixed throttle member and the A retrofitting method for a refrigeration cycle apparatus, characterized in that the refrigeration cycle apparatus according to any one of claims 1 to 4 is provided by installing a dryer.

The refrigerating cycle apparatus and the retrofitting method for the refrigerating cycle apparatus of the present invention are the same refrigerating cycle apparatus as R22 (chlorodifluoromethane) and R2.
It was invented from the difference in the characteristics of 90 (propane). That is, in a refrigeration cycle apparatus in which the compressor, the outdoor heat exchanger, the indoor heat exchanger, etc. are the same, R22 and R2
Comparing the characteristics of 90, the optimum amount of refrigerant that achieves the maximum efficiency is that R290 requires only about half the amount of refrigerant of R22, and in order to achieve an appropriate throttle opening in R290, R22
Therefore, it is necessary to limit the throttle opening rather than the proper throttle opening. This is because the density of R290 is about half that of R22, the filling amount is about half in the same volume device, and the latent heat of vaporization of R290 is about twice as large as that of R22. This is largely due to the fact that the circulation amount is required to be about half to realize it, and the same tendency is obtained when HC refrigerants other than R290 are mixed.

Therefore, a throttle device for a home-use separation type air conditioner designed for R22 is composed of a capillary tube and an expansion valve and is often arranged in an outdoor unit, which is mainly composed of R290. When changing to the HC refrigerant to be used, if a fixed throttle member is inserted into the connection port of the liquid side pipeline on the indoor unit side, an appropriate throttle opening can be realized at R290 as a whole. In addition, a throttle device for a commercial separation type air conditioner designed for R22 is often arranged in an indoor unit, but when changing it to an HC refrigerant containing R290 as a main component, the outdoor unit side is used. If a fixed throttle member is inserted into the connection port of the liquid side pipe of
With 90, an appropriate throttle opening can be realized. If the fixed throttle member is a detachable orifice type fixed throttle member, it can be easily inserted into the connection pipe.

At this time, the liquid side pipe line between the fixed throttle member inserted on the opposite side of the throttle device originally arranged for R22 is circulated as a two-phase refrigerant of liquid phase and gas phase in R290. As a result, there is a side effect of further reducing the refrigerant amount of R290, which is about half that of R22.

If a dryer is inserted in the liquid side conduit or near the connection port between the outdoor unit or the indoor unit and the liquid side conduit, moisture in the air is frozen when the connection pipe is opened. Even if it gets mixed in the cycle device, the dryer adsorbs a small amount of water, so that there is no possibility of causing an ice phenomenon due to the clathrate.

Further, when only R290 (propane) is used, the cooling and heating capacity is reduced to about 85 to 90%. When an inverter-driven compressor is used, the operating frequency is automatically adjusted to increase due to the temperature difference between the indoor set temperature and the outlet temperature, and the R290 pressure at the same capacity is lower than the R22 pressure. Therefore, there is no safety problem. H that is changed when using a compressor whose frequency cannot be changed
When a small amount of R1270 (propylene) or R170 (ethane) is added to R290 as a C refrigerant to adjust the capacity, R1270 is suitable up to about 60% by weight, and R170 is up to about 5% by weight.

In general, an HC refrigerant such as R290 (propane) is R22 at the same temperature as a lubricating oil for a compressor such as mineral oil or alkylbenzene oil which has been conventionally used in R22.
Although it dissolves better than the above, the discharge temperature and discharge pressure in the compressor where the lubricating oil accumulates during operation of the refrigeration cycle device are
At 90, it is lower than R22, and there is no substantial difference in the amount of refrigerant dissolved in the lubricating oil. Therefore, the viscosity of the lubricating oil is reduced by dissolution of the refrigerant to the same extent or to a slightly greater extent. Therefore, R
When changing from 22 to R290, it is not always necessary to change the lubricating oil, but in some cases an additive for improving wear resistance may be injected. After discharging R22 and inserting the fixed throttle member, a vacuum is drawn to fill R290. At this time, even if a small amount of R22 is dissolved in the lubricating oil, the reliability is still low. There is no problem.

As a matter of course, in the case of the new refrigeration cycle apparatus using the HC refrigerant, if throttling devices are provided on both sides of the connecting pipe of the liquid side pipeline, the optimum refrigerant amount for achieving the maximum efficiency is R290. The effect of requiring only half the amount of refrigerant of R22 and the effect of circulating as a two-phase refrigerant of liquid phase and gas phase in the liquid side pipeline, R290 can reduce the amount of refrigerant to less than half that of R22. It is possible to greatly reduce the risk of the strong flammability of R290.

Basically, in order to reduce the amount of refrigerant in the liquid side pipeline, it is necessary to throttle the outdoor unit side during the cooling operation and throttle the indoor unit side during the heating operation. The amount of hold of the refrigerant in the phase flow can be reduced most. Therefore, for example, the orifice type throttle members arranged in both the indoor and outdoor units can be configured as a unidirectional mechanism. Further, when the optimum amount of refrigerant in the cooling operation and the heating operation in one expansion device is different, it is possible to devise expansion devices provided on both sides of the connection pipe of the liquid side pipeline. If the amount of refrigerant during cooling operation is greater than the amount of refrigerant during heating operation, the orifice-type throttle member on the outdoor unit side can be configured to flow with resistance during both heating and cooling operations. Since the two-stage throttle is used, the optimum amount of refrigerant during the heating operation is slightly increased, and the same optimum amount of refrigerant can be achieved during both the heating and cooling operations. If the amount of refrigerant during the heating operation is larger than that during the cooling operation, the orifice-type throttle member on the indoor unit side can be configured to flow with resistance during both the cooling and heating operations. Time is 2
Since the staged throttle is used, the optimum amount of refrigerant during the cooling operation is slightly increased, and the same optimum amount of refrigerant can be achieved during both the cooling and heating operations.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) First, the first embodiment of the present invention
Embodiments will be described with reference to the drawings.

FIG. 1 is a conceptual diagram of a separation type air conditioner using a refrigeration cycle device according to the first embodiment of the present invention. The refrigeration cycle apparatus in the present embodiment is obtained by using the retrofitting method of the refrigeration cycle apparatus of the present invention for the existing refrigeration cycle apparatus for R22.

In FIG. 1, 1 is a compressor driven by an inverter 2, 3 is a four-way valve for switching heating / cooling cycles, 4 is an outdoor heat exchanger, 5 is an expansion valve serving as a throttle device, and 6
Is an accumulator, and these components are housed in the outdoor unit 7. The indoor unit 8 houses the indoor heat exchanger 9 and is installed in the room 10. The gas side and the liquid side of the outdoor unit 7 and the indoor unit 8 are connected by the gas side pipeline 11 and the liquid side pipeline 12, and the liquid lines are connected to each other from the outdoor unit 7 side where the expansion valve 5 is arranged, synthetic zeolite or the like. Connected by a dryer 13 and a liquid-side conduit 12 filled with a liquid, and an orifice type fixed throttle member 14 configured to flow with resistance in both heating and cooling operation,
The gas lines are connected to each other through the gas side pipe line 11 to form a closed circuit. An HC refrigerant such as R290 (propane) changed from R22 is sealed inside the closed circuit to form a known refrigeration cycle device. As a lubricating oil,
Soluble alkylbenzene oil is enclosed in both R22 and HC refrigerant.

Regarding the enclosed HC refrigerant, R2
Although 90 (propane) alone may be used, R290 has a slightly inferior ability and a lower pressure than R22, so in order to adjust these, a small amount of R1270 (propylene) or R170 (ethane) with a lower boiling point than R290 is mixed. You may. Also, a small amount of a nonflammable agent for the HC refrigerant may be added.

The operation of the separation type air conditioner having such a configuration will be described below. That is, during the heating operation, as shown by the solid line in FIG. 1, the HC refrigerant is compressed in the compressor 1 driven by the inverter 2 to become high-temperature and high-pressure vapor, which passes through the four-way valve 3 and the gas side pipeline 11 Is discharged to the indoor heat exchanger 9 in the indoor unit 8. At this time, the indoor heat exchanger 9 functions as a condenser, heats the room 10 by heating the room 10, and the HC refrigerant is condensed and liquefied. The liquefied HC refrigerant reaches the outdoor heat exchanger 4 through the fixed throttle member 14, the liquid side conduit 12, the dryer 13, and the expansion valve 5 in the outdoor unit 7. At this time, the outdoor heat exchanger 4 functions as an evaporator, receives heat from the outside air and evaporates,
It becomes low-pressure steam and is sucked into the compressor 1 through the four-way valve 3 and the accumulator 6. Here, the HC refrigerant condensed and liquefied in the indoor heat exchanger 9 in the indoor unit 8 is once decompressed by the inserted fixed throttle member 14 and further decompressed by the expansion valve 5, so that the opening degree of the expansion valve 5 is R22. Even if it is set to be used for HC, a proper throttle opening can be realized with the HC refrigerant as a whole, and the liquid side conduit 12 from the fixed throttle member 14 to the expansion valve 5 is filled with the refrigerant in the two-phase state. The amount of the refrigerant can be half or less than that of R22.

Next, during the cooling operation, as shown by the broken line in FIG. 1, the outdoor heat exchanger 4 is switched to the condenser by switching the four-way valve 3.
The indoor heat exchanger 9 functions as an evaporator and absorbs heat from the air in the room 10 to cool the room 10. Here, the HC refrigerant condensed and liquefied in the outdoor heat exchanger 4 in the outdoor unit 7 is once decompressed by the expansion valve 5 and further decompressed by the fixed throttle member 14, so that the HC refrigerant has a proper throttle opening as a whole. Since it can be realized and the liquid side conduit 12 from the expansion valve 5 to the fixed throttle member 14 is filled with the two-phase refrigerant,
The amount of the HC refrigerant can be half or less than that of R22.

Further, when the fixed throttle member 14 is inserted into one of the liquid side conduits 12, the dryer 13 is also inserted into the other, so that the moisture in the air is mixed into the refrigeration cycle device when the liquid side conduits 14 are opened. However, due to the evacuation when changing to HC refrigerant and the adsorption of water by the dryer 13,
There is no risk of freezing due to clathrates. The insertion position of the dryer is not limited to the position shown in FIG.

As described above, the refrigeration cycle apparatus in the present embodiment can reduce the risk and operate efficiently by reducing the amount of R290 used as the refrigerant as much as possible. In addition, the retrofitting method of the refrigeration cycle apparatus in the present embodiment can easily replace the existing R22 refrigeration cycle apparatus with the R2.
It is possible to retrofit to a refrigeration cycle device using an HC refrigerant containing 90 as a main component.

In the present embodiment, the refrigeration cycle apparatus of the present invention is obtained by using the retrofitting method of the refrigeration cycle apparatus of the present invention for an existing R22 refrigeration cycle apparatus. However, even if it is newly designed and manufactured, the same configuration is obtained. At this time, in the separation type air conditioner using the refrigeration cycle device according to the present embodiment shown in FIG.
It is needless to say that 3 may be arranged inside the outdoor unit 7 and the fixed throttle member 14 inside the indoor unit 8.

In the present embodiment, the refrigeration cycle apparatus of the present invention has been described as being capable of heating / cooling switching provided with a four-way valve, but it is only for cooling or heating without the four-way valve. It may be.

Further, although the refrigeration cycle apparatus of the present invention has been described as having a dryer in the present embodiment, if the dryer is omitted, the effect of suppressing the icing phenomenon due to the clathrate is lost, but the refrigerant is used. By similarly reducing the amount of R290 used as, the effects of reducing the risk and enabling efficient operation can be obtained in the same manner.

(Second Embodiment) Next, the second embodiment of the present invention will be described.
Embodiments will be described with reference to the drawings. The present embodiment is different from the above-described first embodiment in that the fixed throttle member of the present invention, in the first embodiment, is an orifice configured to flow with resistance during both heating and cooling operation. While the mold fixed diaphragm member was not further limited, this embodiment is concerned with the fixed diaphragm member shown in FIGS. 2 and 3. Therefore, in the present embodiment, the same components as those in the first embodiment are designated by the same reference numerals and will be described with reference to FIG. In addition, the elements that are not particularly described are the same as those in the first embodiment.

FIG. 2 is a sectional view of a fixed diaphragm member according to the second embodiment of the present invention. FIG. 3 is a partial perspective view of the fixed diaphragm member according to the second embodiment of the present invention.

In FIG. 2, the fixed throttle member 14 is one in which two throttle members 17 and 18 having orifice portions 19 and 20 are arranged on both sides of a space 16 in a copper tube 15.
Further, the disks 21, 2 are provided on the space 16 side of the diaphragm members 17, 18.
2 is arranged, and the copper pipe 15 is provided around the throttle members 17 and 18.
And space grooves 23 and 24 are formed between
The side opposite to the space 16 of 8 is formed in a taper shape, and in the copper tube 15, tapered receiving members 25 and 26 that fit with the tapered portions of the throttle members 17 and 18 are arranged. Here, the throttling members 17 and 18 cause the copper tube 15
When the refrigerant circulates inside as shown by the solid line in FIG. 2, the left throttle member 17 is fixed by the left disk 21, and the refrigerant bypasses the orifice portion 19 of the throttle member 17 so that the copper pipe Since it flows through the space groove 23 between the diaphragm 15, the function as the diaphragm device is lost. On the other hand, the right diaphragm member 18 moves to the right, the tapered portion of the diaphragm member 18 fits into the tapered portion of the receiving member 26, and the space groove 22
Is closed and the refrigerant flows only through the orifice portion 20 of the throttle member 18, so that the refrigerant functions as a throttle device. Figure 2
When the refrigerant circulates in the direction opposite to the solid line, the right throttle member 18 does not function as a throttle device, and the left throttle member 17 functions as a throttle device. here,
When changing from R22 to R290 or other HC refrigerant, it is necessary to limit the expansion device, so the diameters of the orifice portions 19 and 20 of the two expansion members 17 and 18 are required during the heating and cooling operation. It may be set separately according to the aperture opening.

Many modifications can be made to the structure of the fixed diaphragm member 14 of FIG. Two diaphragm members 17, 1
The inlet side of the eight orifice portions 19 and 20 may be formed in a tapered shape to stabilize the flow rate characteristic of the refrigerant. Further, a strainer for catching dust may be provided on the outlet side of the two tapered receiving members 25 and 26. Further, although the fixed diaphragm member 14 in FIG. 2 has been described as being composed of two diaphragm members 17 and 18, etc., diaphragm members configured separately may be used in combination, or only one diaphragm member. But it's okay. Furthermore, the fixed throttle member 14 may be brazed and welded, but if it is a flare connection shape or a shape that uses packing, the number of steps for brazing and welding can be reduced, and an oxide film may be formed in the pipe. It is desirable from the standpoint of prevention and reliability.

As described above, the refrigeration cycle apparatus according to the present embodiment operates more efficiently than the refrigeration cycle apparatus according to the first embodiment by including the fixed throttle member according to the present embodiment. be able to.

The refrigeration cycle apparatus of the present invention is the first
In the embodiment described above, it was explained that it may be dedicated to cooling or heating without the four-way valve,
When the fixed throttle member according to the present embodiment is provided, it is limited to the one capable of switching between cooling and heating, which is provided with a four-way valve.

[0042]

As is clear from the above description, the present invention according to claim 1 reduces the risk and enables efficient operation by reducing the amount of R290 used as a refrigerant as much as possible. It is possible to provide a refrigeration cycle device that uses an HC refrigerant containing R290 as a main component. Further, the present invention of claim 5 provides a retrofitting method for a refrigeration cycle apparatus, which easily retrofits an existing refrigeration cycle apparatus for R22 or the like to a refrigeration cycle apparatus using an HC refrigerant containing R290 as a main component. can do.

That is, in the retrofitting method of the refrigeration cycle apparatus of the present invention, in the separation type air conditioner, when the refrigerant is changed from R22 to HC refrigerant containing R290 as a main component, an outdoor or indoor unit for accommodating the expansion device. A fixed throttle member is inserted into the connection port of the liquid side conduit on the unit side located on the opposite side to the side, and an appropriate throttle opening can be realized with HC refrigerant as a whole, and a removable orifice type fixed throttle member. If so, it can be easily inserted into the connection pipe, and the optimum amount of refrigerant during the heating and cooling operation can be adjusted. At this time, the side effect of further reducing the refrigerant amount of R290, which is about half that of R22, is obtained.
The danger to the strong flammability of the refrigerant can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a separation type air conditioner using a refrigeration cycle device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a fixed diaphragm member according to a second embodiment of the present invention.

FIG. 3 is a partial perspective view of a fixed diaphragm member according to a second embodiment of the present invention.

[Explanation of symbols]

1 compressor 2 inverter 3 four-way valve 4 outdoor heat exchanger 5 expansion valve 6 Accumulator 7 outdoor unit 8 indoor units 9 Indoor heat exchanger 10 rooms 11 gas side pipeline 12 Liquid side pipeline 13 Dryer 14 Fixed diaphragm member 15 Copper tube 16 spaces 17, 18 diaphragm member 19, 20 Orifice part 21,22 disk 23, 24 space groove 25,26 Receiving member

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shozo Funakura 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-9-264619 (JP, A) JP-A-7- 174439 (JP, A) Actual development Sho 60-12155 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F25B 1/00 395 F25B 13/00 F25B 45/00

Claims (5)

(57) [Claims] 1. An outdoor unit having a compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, a liquid side conduit and a gas side conduit connecting the outdoor unit and the indoor unit, A throttling device included in the outdoor unit or the indoor unit, and a fixing device that is installed near a connection port of the liquid side pipeline that does not include the throttling device of the outdoor unit or the indoor unit A refrigeration cycle device comprising: a throttle member, wherein the refrigerant is an HC refrigerant containing R290 (propane) as a main component. 2. The dryer according to claim 1, wherein a dryer is provided inside the liquid side conduit or near a connection port between the liquid side conduit and either the outdoor unit or the indoor unit. Refrigeration cycle device. 3. The refrigerating cycle according to claim 1, wherein the HC refrigerant is R290 (propane) or a refrigerant obtained by mixing R290 with R1270 (propylene) and / or R170 (ethane). apparatus. 4. An air-conditioning switching four-way valve, wherein the fixed throttle member is provided with one orifice portion that functions only in one of the directions of the flow of the HC refrigerant, or depending on the direction of the flow of the HC refrigerant. , Two orifice portions, only one of which functions.
The refrigeration cycle apparatus according to any one of 1 to 3. 5. An outdoor unit having a compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, a liquid side pipeline and a gas side pipeline connecting the outdoor unit and the indoor unit, For a refrigeration cycle apparatus including an outdoor unit or a throttle device included in the indoor unit, while changing the refrigerant to the HC refrigerant,
A retrofitting method for a refrigeration cycle apparatus, wherein the refrigeration cycle apparatus according to any one of claims 1 to 4 is provided by installing the fixed throttle member or the fixed throttle member and the dryer.