JP2009068737A

JP2009068737A - Refrigerator

Info

Publication number: JP2009068737A
Application number: JP2007236040A
Authority: JP
Inventors: Takanori Tanigawa; 貴紀谷川; Makoto Okabe; 誠岡部; Akira Nishizawa; 章西澤; Mutsumi Kato; 睦加藤
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2007-09-12
Filing date: 2007-09-12
Publication date: 2009-04-02
Anticipated expiration: 2027-09-12
Also published as: JP4789891B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerator capable of checking leakage of each weld portion of an evaporator and a capillary tube, and the evaporator and a suction tube. <P>SOLUTION: This refrigerator comprises a compressor 1 for compressing a gas refrigerant of low pressure/low temperature, and discharging a gas refrigerant of high pressure/high temperature, a condenser 2 for condensing the gas refrigerant discharged from the compressor 1 to be a liquid refrigerant of high pressure, a capillary tube 4 for decompressing and expanding the liquid refrigerant of high pressure to be a gas-liquid two-phase refrigerant of low pressure, an evaporator 5 for evaporating the gas-liquid two-phase refrigerant of low pressure to be a gas refrigerant of low pressure, an accumulator 6 for storing the liquid refrigerant, a suction pipe 7 for connecting the accumulator 6 and the compressor 1, a check valve 8 disposed in the suction pipe 7, and a charge pipe 10 connected between the accumulator 6 and the check valve 8 for sealing a gas for leakage test in checking the leakage of the weld portion on a low pressure side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

この発明は、冷蔵庫に関する。詳しくは、逆止弁搭載の冷蔵庫における製造時のリークチェック、運転時の省エネ効果に関する。 The present invention relates to a refrigerator. Specifically, the present invention relates to a leak check at the time of manufacture in a refrigerator equipped with a check valve and an energy saving effect during operation.

冷凍サイクルとして、以下に示すような構成の冷蔵庫が提案されている。即ち、冷凍サイクルは、低圧シェルレシプロ圧縮機、コンデンサ（凝縮器）、毛細管、蒸発器、アキュムレータ、逆止弁、吸入管が順番に接続されている。逆止弁を設けたことにより、圧縮機の運転停止時および霜取運転時に吸入管に液冷媒の流入を防止することにより、吸入管内での液冷媒の偶発的な蒸発に伴う急激な冷媒の移動を押え、アキュムレータ内に冷媒が逆流したことに起因する冷媒音を低減し静音な冷蔵庫を提供することができる（例えば、特許文献１参照）。
特開２００２−００５５５７号公報 As a refrigeration cycle, a refrigerator having the following configuration has been proposed. That is, in the refrigeration cycle, a low-pressure shell reciprocating compressor, a condenser (condenser), a capillary tube, an evaporator, an accumulator, a check valve, and a suction pipe are connected in order. By providing a check valve, the flow of liquid refrigerant into the suction pipe is prevented when the compressor is shut down and during defrosting operation. It is possible to provide a quiet refrigerator that suppresses the movement and reduces the noise of the refrigerant caused by the reverse flow of the refrigerant into the accumulator (for example, see Patent Document 1).
JP 2002-005557 A

上記特許文献１の冷凍サイクルでは、蒸発器と毛細管及び蒸発器と吸入管の溶接部のリークテストは、各溶接部を溶接後に毛細管、蒸発器、吸入管内にリークテスト用ガスを封入し加圧して行う。しかしながら、逆止弁を設けている吸入管側からリークテスト用ガスを封入することはできないため、毛細管側からリークテスト用ガスを封入加圧しなければならなかった。従って毛細管がリークテスト用ガス封入の抵抗となり、封入が極めて長時間となるという課題があった。 In the refrigeration cycle of the above-mentioned Patent Document 1, the leak test of the welded portion of the evaporator and the capillary tube and the evaporator and the suction tube is performed by sealing and welding the leak test gas in the capillary tube, the evaporator, and the suction tube after welding each welded portion. Do it. However, since the leak test gas cannot be sealed from the suction pipe side where the check valve is provided, the leak test gas must be sealed and pressurized from the capillary side. Accordingly, there is a problem that the capillary tube becomes a resistance for gas filling for the leak test and the filling time is extremely long.

この発明は、上記のような課題を解決するためになされたもので、蒸発器と毛細管、蒸発器と吸入管等の溶接部のリークチェックを短時間で行うことができる冷蔵庫を提供することを目的とする。 The present invention has been made to solve the above-described problems, and provides a refrigerator capable of performing a leak check of a welded portion such as an evaporator and a capillary tube, an evaporator and a suction tube in a short time. Objective.

この発明に係る冷蔵庫は、低圧・低温のガス冷媒を圧縮して高圧・高温のガス冷媒を吐出する圧縮機と、圧縮機から吐出されたガス冷媒を凝縮させて高圧の液冷媒に凝縮させる凝縮器と、高圧の液冷媒を減圧膨張させて低圧の気液二相冷媒にする減圧装置と、低圧の気液二相冷媒を蒸発させて低圧のガス冷媒にする蒸発器と、液冷媒を貯留するアキュムレータと、アキュムレータと圧縮機とを接続する吸入管と、吸入管に設けられた逆止弁と、アキュムレータと逆止弁との間に接続され、低圧側の溶接部のリークチェック時にリークテスト用ガスを封入するチャージパイプとを備えたことを特徴とする。 The refrigerator according to the present invention includes a compressor that compresses a low-pressure / low-temperature gas refrigerant and discharges the high-pressure / high-temperature gas refrigerant, and a condensation that condenses the gas refrigerant discharged from the compressor into a high-pressure liquid refrigerant. A decompressor that decompresses and expands the high-pressure liquid refrigerant into a low-pressure gas-liquid two-phase refrigerant, an evaporator that evaporates the low-pressure gas-liquid two-phase refrigerant into a low-pressure gas refrigerant, and stores the liquid refrigerant The accumulator, the suction pipe connecting the accumulator and the compressor, the check valve provided in the suction pipe, and connected between the accumulator and the check valve. And a charge pipe for enclosing a working gas.

この発明に係る冷蔵庫は、アキュムレータと逆止弁との間に接続され、低圧側の溶接部のリークチェック時にリークテスト用ガスを封入するチャージパイプを備えたことにより、蒸発器と毛細管、蒸発器と吸入管等の溶接部のリークチェックを短時間で行うことができる。 The refrigerator according to the present invention is provided with a charge pipe that is connected between an accumulator and a check valve and encloses a leak test gas at the time of leak check of a welded portion on the low-pressure side. In addition, it is possible to perform a leak check of a welded part such as a suction pipe in a short time.

実施の形態１．
図１、図２は実施の形態１を示す図で、図１は冷蔵庫５０における冷凍サイクルの配置を示す模式図、図２は冷蔵庫５０における冷凍サイクルの冷媒流路を示す模式図である。図３は比較のために示す参考図で、従来の冷蔵庫５０における冷凍サイクルの冷媒流路を示す模式図である。 Embodiment 1 FIG.
1 and 2 are diagrams showing the first embodiment. FIG. 1 is a schematic diagram showing the arrangement of the refrigeration cycle in the refrigerator 50. FIG. 2 is a schematic diagram showing the refrigerant flow path of the refrigeration cycle in the refrigerator 50. FIG. 3 is a reference diagram for comparison, and is a schematic diagram showing a refrigerant flow path of a refrigeration cycle in a conventional refrigerator 50.

以下、図１及び図２により、冷蔵庫５０の冷凍サイクルの構成を説明する。冷蔵庫５０における冷凍サイクルは、低圧シェルレシプロ圧縮機１（密閉容器内が低圧の圧縮機の一例）、コンデンサ２（凝縮器）、キャビネットパイプ２ａ、ドライヤ３、毛細管４（減圧装置の一例）、蒸発器５、アキュムレータ６、逆止弁８、及び吸入管７を順番に接続している。また、アキュムレータ６と逆止弁８との間に、チャージパイプ１０が接続されている。 Hereinafter, the configuration of the refrigeration cycle of the refrigerator 50 will be described with reference to FIGS. 1 and 2. The refrigeration cycle in the refrigerator 50 includes a low-pressure shell reciprocating compressor 1 (an example of a low-pressure compressor in a sealed container), a condenser 2 (condenser), a cabinet pipe 2a, a dryer 3, a capillary tube 4 (an example of a decompression device), and evaporation. The container 5, the accumulator 6, the check valve 8, and the suction pipe 7 are connected in order. A charge pipe 10 is connected between the accumulator 6 and the check valve 8.

低圧シェルレシプロ圧縮機１は、冷蔵庫５０の背面下部に位置する機械室に配置される。 The low-pressure shell reciprocating compressor 1 is disposed in a machine room located at the lower back of the refrigerator 50.

コンデンサ２（凝縮器）は、冷蔵庫５０の断熱箱体の背面及び側面に配置される。また、背面及び側面に追加して、天面または底面にも配置される場合がある。さらに、背面及び側面に追加して、天面及び底面にも配置される場合がある。図１では、冷蔵庫５０の背面及び側面及び底部に配置されるケースで、背面及び側面の図示は省略している。蒸発器５に付着した霜は、蒸発器５の直下に設けられた霜取ヒータ９で除霜される。その除霜水は、冷蔵庫５０の底部に配置される図示しない蒸発皿に溜まる。そして、コンデンサ２により加熱されて蒸発する。 The condenser 2 (condenser) is disposed on the back and side surfaces of the heat insulating box of the refrigerator 50. In addition to the back surface and the side surface, the top surface or the bottom surface may be arranged. Further, in addition to the back and side surfaces, the top and bottom surfaces may also be arranged. In FIG. 1, the back and side surfaces of the refrigerator 50 are not shown in the case of the case disposed on the back and side surfaces and the bottom. The frost adhering to the evaporator 5 is defrosted by a defrost heater 9 provided immediately below the evaporator 5. The defrost water collects in an evaporating dish (not shown) arranged at the bottom of the refrigerator 50. Then, it is heated by the capacitor 2 and evaporated.

キャビネットパイプ２ａは、冷蔵庫５０前面のキャビネット部の露付き防止用に折り曲げて配置される。図１のＲは、冷蔵室を示す。また、Ｖは野菜室を示す。さらに、Ｆは冷凍室を示す。 The cabinet pipe 2a is bent and arranged to prevent dew condensation on the cabinet portion on the front surface of the refrigerator 50. R of FIG. 1 shows a refrigerator compartment. Moreover, V shows a vegetable room. Further, F indicates a freezer compartment.

ドライヤ３は、機械室に配置される。ドライヤ３には、シリカゲルなどの乾燥剤が封入されている。乾燥剤が冷媒に混入した水分を除く。 The dryer 3 is disposed in the machine room. A desiccant such as silica gel is enclosed in the dryer 3. Removes moisture mixed with desiccant in the refrigerant.

毛細管４は、機械室に配置されたドライヤ３を経て冷蔵庫５０背面のウレタン（断熱材）内部に折り曲げられて配置される。 The capillary tube 4 is bent and disposed inside the urethane (heat insulating material) on the back of the refrigerator 50 through the dryer 3 disposed in the machine room.

蒸発器５は、冷蔵庫５０背面の冷却器室に配置される。蒸発器５では、冷媒が庫内の空気と熱交換を行ない冷気が生成される。蒸発器５で生成された冷気は、図示しない送風ファンにより強制的に庫内へ送られる。 The evaporator 5 is disposed in a cooler chamber on the back of the refrigerator 50. In the evaporator 5, the refrigerant exchanges heat with the air in the cabinet to generate cold air. The cold air generated by the evaporator 5 is forcibly sent into the cabinet by a blower fan (not shown).

アキュムレータ６も、冷蔵庫５０背面に配置される。アキュムレータ６は、上流側（蒸発器５）が下になるように配置される。アキュムレータ６にはガス冷媒と液冷媒とが存在する。アキュムレータ６の内容積は、圧縮機１の必要貯油量よりも大きく、且つ吸入管７へ液冷媒が流入しないような内容積を有する。 The accumulator 6 is also disposed on the back of the refrigerator 50. The accumulator 6 is arranged so that the upstream side (evaporator 5) is on the bottom. The accumulator 6 includes a gas refrigerant and a liquid refrigerant. The internal volume of the accumulator 6 is larger than the required oil storage amount of the compressor 1 and has an internal volume that prevents liquid refrigerant from flowing into the suction pipe 7.

リークチェック用のチャージパイプ１０は、冷蔵庫５０内背面と機械室を結ぶように配置される。チャージパイプ１０の端末は機械室に位置する。 The leak check charge pipe 10 is arranged so as to connect the rear surface of the refrigerator 50 and the machine room. The terminal of the charge pipe 10 is located in the machine room.

逆止弁８は、冷蔵庫５０内背面の吸入管７に設けられる。チャージパイプ１０の下流側に設けられる。逆止弁８は上流側が下、下流側が上になるように略垂直に設置される。さらに、逆止弁８の下流側の冷媒配管は、逆止弁８の出口から略垂直になるように取り付けられる。逆止弁８の出口から略垂直に延びる冷媒配管を垂直部８ａとする。尚、逆止弁８は上流側が上、下流側が下になるように略垂直に設置してもよい。この場合は、垂直部８ａが不要となる。 The check valve 8 is provided in the suction pipe 7 on the back of the refrigerator 50. Provided on the downstream side of the charge pipe 10. The check valve 8 is installed substantially vertically so that the upstream side is down and the downstream side is up. Further, the refrigerant pipe on the downstream side of the check valve 8 is attached so as to be substantially vertical from the outlet of the check valve 8. A refrigerant pipe extending substantially vertically from the outlet of the check valve 8 is defined as a vertical portion 8a. The check valve 8 may be installed substantially vertically so that the upstream side is up and the downstream side is down. In this case, the vertical portion 8a is not necessary.

吸入管７は冷蔵庫５０背面側のウレタン（断熱材）内に折り曲げられて配置される。吸入管７は機械室の圧縮機１に接続する。 The suction pipe 7 is bent and arranged in urethane (heat insulating material) on the back side of the refrigerator 50. The suction pipe 7 is connected to the compressor 1 in the machine room.

吸入管７と毛細管４は冷蔵庫５０背面のウレタン内部において、冷媒の流れが対向流となるように半田により配管同士を結合し熱交換を行う。 The suction pipe 7 and the capillary 4 exchange heat by connecting the pipes with solder so that the refrigerant flows in the opposite direction inside the urethane on the back of the refrigerator 50.

以上のように構成された冷凍サイクルにおいて、圧縮機１より吐出された冷媒は、コンデンサ２において凝縮され高圧の液冷媒となる。ドライヤ３で冷媒中の水分が除かれる。次いで、膨張機構である毛細管４にて減圧膨張し低圧の気液二相冷媒となる。低圧の気液二相冷媒は蒸発器５で蒸発する。蒸発器５で蒸発しきれない冷媒はアキュムレータ６に溜まる。そして、冷媒ガスのみが逆止弁８、吸入管７を通って圧縮機１の密閉容器内に吸入される。 In the refrigeration cycle configured as described above, the refrigerant discharged from the compressor 1 is condensed in the condenser 2 to become a high-pressure liquid refrigerant. The moisture in the refrigerant is removed by the dryer 3. Subsequently, it expands under reduced pressure in the capillary 4 which is an expansion mechanism, and becomes a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant evaporates in the evaporator 5. The refrigerant that cannot be evaporated by the evaporator 5 is accumulated in the accumulator 6. Then, only the refrigerant gas is sucked into the sealed container of the compressor 1 through the check valve 8 and the suction pipe 7.

一方、圧縮機１の運転停止時および霜取運転時には、冷凍サイクルの圧縮機１から毛細管４までの高圧側から、低圧側である蒸発器５へ冷媒が流入しアキュムレータ６まで液冷媒が流入する。 On the other hand, when the compressor 1 is stopped and defrosted, the refrigerant flows from the high pressure side from the compressor 1 to the capillary 4 in the refrigeration cycle into the evaporator 5 on the low pressure side, and the liquid refrigerant flows into the accumulator 6. .

また、上記の冷凍サイクルにおいて、圧縮機１の運転停止時および霜取運転中には、逆止弁８が圧縮機１からアキュムレータ６の方向へ冷媒が逆流すると弁を閉じ、吸入管７を閉塞する。 In the refrigeration cycle, when the operation of the compressor 1 is stopped and during the defrosting operation, the check valve 8 closes the valve when the refrigerant flows backward from the compressor 1 to the accumulator 6 and closes the suction pipe 7. To do.

一方、圧縮機１の運転中は逆止弁８が開き、吸入管７が連通されることにより冷凍サイクルが形成される。 On the other hand, during the operation of the compressor 1, the check valve 8 is opened and the suction pipe 7 is communicated to form a refrigeration cycle.

このため、圧縮機１の運転停止時および霜取運転時には圧縮機１からアキュムレータ６方向へ冷媒が逆流すると逆止弁８が閉となる。すると、吸入管７を閉塞するので冷媒が吸入管７を通ってアキュムレータ６へ逆流するのを防止することができる。 For this reason, the check valve 8 is closed when the refrigerant flows backward from the compressor 1 toward the accumulator 6 when the operation of the compressor 1 is stopped and during the defrosting operation. Then, since the suction pipe 7 is closed, it is possible to prevent the refrigerant from flowing back to the accumulator 6 through the suction pipe 7.

また、冷媒の流れが吸入管７から圧縮機１の密閉容器方向のときには、逆止弁８は開である。そのため冷媒が冷凍サイクル中を流動し通常の冷却運転を行うことができる。 When the refrigerant flows from the suction pipe 7 toward the closed container of the compressor 1, the check valve 8 is open. Therefore, the refrigerant flows in the refrigeration cycle, and a normal cooling operation can be performed.

蒸発器５と毛細管４及び蒸発器５から吸入管７へ至る各溶接部（低圧側の溶接部）のリークテストをする際には、各溶接部を溶接後に毛細管４、蒸発器５、吸入管７内にリークテスト用ガスを封入し加圧する。 When performing a leak test of the welds (low pressure side welds) from the evaporator 5 and the capillary 4 and the evaporator 5 to the suction pipe 7, the capillary 4, the evaporator 5, and the suction pipe are welded after the welds are welded. 7 is filled with a leak test gas and pressurized.

図３の参考図に示す従来の冷蔵庫では、蒸発器５と毛細管４及び蒸発器５と吸入管７等の各溶接部のリークテスト時に、逆止弁８を設けている吸入管７側からリークテスト用ガスを封入することはできない。そのため、毛細管４側からリークテスト用ガスを封入加圧しなければならない。従って毛細管４がリークテスト用ガス封入の抵抗となり、封入が極めて長時間となるという課題があった。 In the conventional refrigerator shown in the reference diagram of FIG. 3, the leak from the suction pipe 7 side where the check valve 8 is provided at the time of the leak test of each welded portion such as the evaporator 5, the capillary tube 4, the evaporator 5, and the suction pipe 7. Test gas cannot be sealed. Therefore, the leak test gas must be sealed and pressurized from the capillary 4 side. Accordingly, there is a problem that the capillary 4 becomes a resistance for leak test gas sealing, and the sealing takes a very long time.

本実施の形態では、毛細管４の片端末を封止した状態で、吸入管７の片端末もカプラ等で塞ぎながら、逆止弁８とアキュムレータ６の間に設けたチャージパイプ１０からリークチェック用ガスを封入する。そのため、蒸発器５等にリークチェック用ガスを速やかに封入することができる。且つ充分な加圧を加えることができる。 In the present embodiment, the one end of the capillary tube 4 is sealed, and the one end of the suction tube 7 is closed with a coupler or the like, and the leak pipe is used for a leak check from the charge pipe 10 provided between the check valve 8 and the accumulator 6. Fill with gas. Therefore, the leak check gas can be quickly sealed in the evaporator 5 or the like. And sufficient pressurization can be applied.

そしてリークチェック終了後に、チャージパイプ１０の機械室側片端末を閉鎖処理する。それにより、逆止弁８の機能を損なうことなく圧縮機１の運転停止時および霜取運転中におけるアキュムレータ６内への逆流を防ぐことができる。 Then, after the leak check is completed, the machine room side terminal of the charge pipe 10 is closed. Thereby, backflow into the accumulator 6 can be prevented when the operation of the compressor 1 is stopped and during the defrosting operation without impairing the function of the check valve 8.

また、圧縮機１の運転停止時および霜取運転時には逆止弁８の下流部に液冷媒が溜まる。逆止弁８を上流側が下、下流側が上になるように略垂直に設置し、さらに逆止弁８の下流部に垂直部８ａを設ける。それにより、逆止弁８を略垂直に設置しない、さらに逆止弁８の下流部に垂直部８ａを設けない場合に比べ、圧縮機１の運転停止中および霜取運転中には逆止弁８の弁の自重に加え、溜まった液冷媒の重さにより、高圧側から低圧側の吸入管７に液冷媒が流入しにくくなる。よって高圧側の高温の冷媒の低圧側への移動が抑えられ、蒸発器５の温度上昇を抑えることができる。そのため、省エネ効果を得ることができる。 In addition, liquid refrigerant accumulates in the downstream portion of the check valve 8 when the compressor 1 is stopped and defrosted. The check valve 8 is installed substantially vertically so that the upstream side is on the lower side and the downstream side is on the upper side. As a result, the check valve 8 is not installed substantially vertically, and the check valve is not operated during the operation of the compressor 1 and during the defrosting operation, compared to a case where the vertical portion 8a is not provided downstream of the check valve 8. In addition to the weight of the valve 8, the weight of the accumulated liquid refrigerant makes it difficult for the liquid refrigerant to flow into the suction pipe 7 on the low pressure side from the high pressure side. Accordingly, the movement of the high-temperature refrigerant on the high-pressure side to the low-pressure side can be suppressed, and the temperature rise of the evaporator 5 can be suppressed. Therefore, an energy saving effect can be obtained.

以上のことにより、本実施の形態の冷蔵庫は、蒸発器５と毛細管４及び蒸発器５と吸入管７との各溶接部のリークチェックに要する時間を、逆止弁８とアキュムレータ６との間にリークチェック用ガス封入のためのチャージパイプ１０を設け、そのチャージパイプ１０からリークチェック用ガスを封入することで短時間でリークチェックすることができる。 As described above, the refrigerator according to the present embodiment is configured so that the time required for the leak check of each welded portion between the evaporator 5 and the capillary 4 and between the evaporator 5 and the suction pipe 7 is between the check valve 8 and the accumulator 6. By providing a charge pipe 10 for leak check gas filling in and charging the leak check gas from the charge pipe 10, the leak check can be performed in a short time.

実施の形態１を示す図で、冷蔵庫５０における冷凍サイクルの配置を示す模式図。FIG. 5 shows the first embodiment and is a schematic diagram showing the arrangement of the refrigeration cycle in the refrigerator 50. FIG. 実施の形態１を示す図で、冷蔵庫５０における冷凍サイクルの冷媒流路を示す模式図。FIG. 5 shows the first embodiment and is a schematic diagram showing a refrigerant flow path of a refrigeration cycle in the refrigerator 50. FIG. 比較のために示す参考図で、従来の冷蔵庫５０における冷凍サイクルの冷媒流路を示す模式図。It is a reference figure shown for a comparison, and is a schematic diagram which shows the refrigerant | coolant flow path of the refrigerating cycle in the conventional refrigerator 50. FIG.

Explanation of symbols

１圧縮機、２コンデンサ、２ａキャビネットパイプ、３ドライヤ、４毛細管、５蒸発器、６アキュムレータ、７吸入管、８逆止弁、８ａ垂直部、９霜取ヒータ、１０チャージパイプ、５０冷蔵庫。 1 compressor, 2 condenser, 2a cabinet pipe, 3 dryer, 4 capillary tube, 5 evaporator, 6 accumulator, 7 suction pipe, 8 check valve, 8a vertical part, 9 defrost heater, 10 charge pipe, 50 refrigerator.

Claims

A compressor that compresses low-pressure / low-temperature gas refrigerant and discharges high-pressure / high-temperature gas refrigerant;
A condenser that condenses the gas refrigerant discharged from the compressor and condenses it into a high-pressure liquid refrigerant;
A decompression device that expands the high-pressure liquid refrigerant under reduced pressure to form a low-pressure gas-liquid two-phase refrigerant;
An evaporator that evaporates the low-pressure gas-liquid two-phase refrigerant into a low-pressure gas refrigerant;
An accumulator for storing liquid refrigerant;
A suction pipe connecting the accumulator and the compressor;
A check valve provided in the suction pipe;
A refrigerator comprising: a charge pipe connected between the accumulator and the check valve and enclosing a leak test gas when checking a leak of a welded portion on a low pressure side.

The refrigerator according to claim 1, wherein the compressor is a low-pressure compressor in a sealed container.

The refrigerator according to claim 1 or 2, wherein the check valve is installed substantially vertically so that the upstream side is down and the downstream side is up.

The refrigerant pipe on the downstream side of the check valve is attached so as to be substantially vertical from an outlet of the check valve, and forms a vertical portion extending substantially vertically from the outlet of the check valve. Item 4. The refrigerator according to any one of Items 1 to 3.

The refrigerator according to claim 1 or 2, wherein the check valve is installed substantially vertically so that the upstream side is up and the downstream side is down.