Detailed process of refrigeration compressor replacement

Detailed process of refrigeration compressor replacement After confirming that there is only a problem with the compressor and it needs to be replaced, proceed to prepare for the replacement of the compressor. Specific steps are as follows: 1. Power off Before replacing the compressor, be sure to cut off the power supply of the unit. Otherwise there will be a risk of electric shock. When removing the power supply of the compressor, the identification of each wire and the corresponding terminal should be done to facilitate the restoration of the wiring after maintenance. Second, put the refrigerant Use the inner hexagon to open the high and low pressure side valves, pay attention to the ventilation of the working environment, so as not to suffocate the operator; the speed of the refrigerant should not be too fast, so as to avoid the operator being injured by the refrigerant. If conditions permit, the refrigerant should be recovered rather than directly discharged to protect the environment. 3. Remove the suction and exhaust pipes Before removing the suction and exhaust pipes, ensure that the refrigerant in the system has been exhausted. Heat the welding port with gas welding. After the solder melts at the welding port, pull out the suction and exhaust pipes. During the entire welding process, be sure to fill with nitrogen. The nitrogen pressure is 0.5±0.1kgf/cm2 to avoid the oxidation of the copper pipe to produce oxide scale. Also pay attention to whether there are impurities or foreign bodies on the inner wall of the copper pipe. When welding, pay attention to controlling the flame direction, avoiding the casing and sponge. Wire, etc. 4. Replace the compressor and connect the suction and exhaust pipes When the compressor is replaced with a new one, the inclination angle of the compressor must not be greater than 45° during the process of compressor handling. The rubber plug of the compressor must be exhausted first and then the suction tube. The interval between the rubber plug and the welded piping should not exceed 10 minutes to prevent air moisture and impurities from entering the system and affecting the performance of the unit. Before welding, remove oil, oxides, burrs and other debris on the surface of the welding point of the connecting pipe and the joint to ensure the cleanness and dryness of the welding joint surface. Nitrogen must be filled during the entire welding process. The nitrogen pressure is 0.5±0.1kgf/cm2, and ensure that the nitrogen reaches the welding position to avoid oxidation of the copper pipe at the welding place. When welding, pay attention to controlling the flame direction, avoiding the casing and sponge. Wire, etc. V. Packing and leak detection After the suction and exhaust pipes are welded, it is necessary to keep the pressure and check the leakage. The gas used for holding pressure can only be inert gases such as nitrogen and carbon dioxide. It is strictly forbidden to substitute air, oxygen, acetylene, refrigerant, etc. to avoid safety accidents. Before pressing, the pressure test instrument should be connected to the system pressure test leak detection pipeline, and the compressed gas cylinder should be connected according to safety requirements to check the opening of each valve of the system First press the pressure to 0.3MPa and then stop the pressure, observe 5 minutes to check whether the pressure has dropped significantly; raise the pressure again to 1.5MPa and stop the pressure, observe 5 minutes to check whether the pressure has dropped significantly; then increase the pressure to the specified Pressure (about 2.6MPa for R22 system and about 3.8MPa for R410a system), and record the ambient temperature. After standing for 24 hours, the pressure drop is within 0.02MPa (temperature change of 1℃, pressure change of about 0.01MPa). If the holding pressure fails, it indicates that the system is leaking. Be sure to check the system for leaks. Investigate and deal with the leakage and then re-weld or repair the welding, and then repeat the above pressure holding steps until it is qualified. 6. Vacuum Before any system needs to be filled with refrigerant after pressure installation and leak detection, the system must be evacuated to remove air and moisture from the system. It is strictly forbidden to use refrigerant to purge the pipeline for emptying. This method is difficult to completely remove the air and moisture in the system, especially when the system piping is long. It is strictly forbidden to use the compressor exhaust to evacuate, which will cause the compressor to burn out. Vacuuming with a vacuum pump is the only way to ensure that the system excludes air and moisture. When vacuuming, it is necessary to select a suitable vacuum pump according to the length of the refrigerant pipe. If the vacuum pump is too small, the vacuuming time will be too long, or the required vacuum will not be achieved. 1. Before evacuating, the gas used for holding pressure in the system should be discharged cleanly, and the gauge pressure shall be reduced to 0MPa. 2. Connect the common connector of the pressure gauge to the suction interface on the vacuum pump; connect the high and low pressure interface heads on the pressure gauge to the inspection valves on the high and low pressure sides of the system, respectively. When the valve in the pressure gauge is closed, open the service valve to approximately the middle of the front and rear seats. 3. Start the vacuum pump and slowly open the pressure gauge tube valve to start vacuuming. The suction pressure of the vacuum pump must be limited by means of a pressure gauge tube valve to avoid overloading the vacuum pump motor. 4. After the vacuum reaches -0.1MPa (gauge pressure -1kgf/cm2), continue to pump for 0.5 to 1 hour, close the high and low pressure shut-off valves, and stop the vacuum pump. 5. After the evacuation is completed, keep it for 6 hours, and the refrigerant can be charged without changing the vacuum. 6. If the vacuum cannot be maintained, it indicates that the system has a leak, and the system needs to be re-checked for leaks and repaired the leaked points to pass. Seven, filling refrigerant The filling volume of the unit should be calculated through strict calculation according to the requirements of the nameplate and the length of the connecting pipeline of the internal and external machines. When infusion, an electronic scale must be used to accurately measure the amount of refrigerant infusion. Refrigerant is filled into the liquid tube side in liquid form, and observe the electronic scale until the required filling volume. If the system is not turned on and cannot be added to the system, let the system run at the full load of refrigeration, and the refrigerant is charged into the trachea side in gaseous form, and observe the electronic scale until the required perfusion amount is reached. 8. Commissioning Restore electrical components such as compressor electric heating belt and temperature sensor to their original positions. Restore power and ensure the unit is well grounded. And jog the compressor to see if it reverses. Start trial operation. Listen to the abnormal noise of the compressor and fan, whether the operation of each mode of air conditioning is normal, and whether the current of the unit is within a reasonable range. After everything is normal, the unit maintenance is completed. The replacement and maintenance of other air-conditioning components (such as four-way valves, electronic expansion valves, etc.) are similar to compressors, and should be strictly installed and operated in accordance with the specifications.

Recent related posts

06/14/2020

Detailed process of refrigeration compressor replacement

06/14/2020

Causes of liquid shock in refrigeration compressors

Causes of liquid shock in refrigeration compressors 1) Too much refrigerant is added to the entire refrigeration system. 　　 2) The throttle valve is opened too large, or the adjustment is malfunctioning. 　　 3) The evaporation area is too sm器2䀀ￜ皥䖒皦즠Ʋ煔क़㲈Ʋ䌁皦ᮔǅ༬皧煞क़Ѐ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠ƲبǜV /펔B䌁皦 ᮔǅ'鱤ǆၜ먢䇨珵呈ᠾ뤂ᐱ⿇⬿먲僧ᐱ㥲ᐲ�僬㣢ᐲᠾ랖僧ք識�僬㣢ᐲ臆S㥲ᐲᬄğ識理艏S杴識杴㥲ᐲ

06/14/2020

Disassembly and maintenance of industrial screw refrigeration compressor

Disassembly and maintenance of industrial screw refrigeration compressor 1. Working principle, movement and movement characteristics of screw refrigeration compressor Screw refrigeration compression belongs to volumetric refrigeration compressor. It器2䀀ￜ皥䖒皦즠Ʋ嫜ི㲈Ʋ䌁皦ᮔǅ༬皧嫦ིЀ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠ƲبǜV /펔B䌁皦 ᮔǅ'鱤ǆၜ먢䇨珵呈ᠾ뤂ᐱ

06/14/2020

The specific operation method of screw refrigeration compressor maintenance

Before the screw compressor must be overhauled, if possible, unload the slide valve to the "0" position, shut down normally, and cut off the power supply. The pipeline connected to the compressor should be cut off and the refrigerant and lubricating oil i器2䀀ￜ皥䖒皦즠Ʋ煔क़㲈Ʋ䌁皦ᮔǅ༬皧煞क़Ѐ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠Ʋبǜ

06/14/2020

An accident analysis of refrigeration compressor

An accident analysis of refrigeration compressor A major refrigerator damage accident occurred in the refrigeration workshop of a meat joint processing plant. The refrigeration workshop of the factory was equipped with 2 single-stage two-stage ammonia re器2䀀ￜ皥䖒皦즠Ʋ嫜ི㲈Ʋ䌁皦ᮔǅ

06/14/2020

Precautions for use of refrigeration compressor overload protector

The overload protector of the compressor for air-conditioning generally adopts a sudden bimetal protector, which is composed of a heating wire, a bimetal and two static contacts, which are connected in series in the compressor circuit. When the current in器2䀀ￜ皥䖒皦즠Ʋ煔क़㲈Ʋ䌁皦ᮔǅ༬皧煞क़Ѐ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠ƲبǜV /펔B䌁皦 ᮔǅ'鱤ǆၜ먢䇨珵呈ᠾ뤂ᐱ⿇⬿먲僧ᐱ㥲ᐲ�僬㣢ᐲᠾ랖僧ۂ識�僬㣢ᐲ臆S㥲ᐲᬄğ識理艏S杴識杴㥲ᐲ

06/14/2020

What to do if the refrigeration compressor is damaged

What to do if the refrigeration compressor is damaged After the refrigeration compressor in the refrigeration system is damaged, the new compressor cannot be replaced directly because there may be some incentives for the refrigeration compressor to be da器2䀀ￜ皥䖒皦즠Ʋ嫜ི㲈Ʋ䌁皦ᮔǅ༬皧嫦ིЀ呄ᠾ鹨់༹皧ࠄ00령

06/14/2020

Comparison of working principle of single screw and twin screw refrigeration compressors

Comparison of working principle of single screw and twin screw refrigeration compressors 1. Twin screw compressor 　　 Twin-screw refrigeration compressor is an energy-adjustable oil-injected compressor. Its three consecutive processes of suction, c器2䀀ￜ皥䖒皦즠Ʋ煔क़㲈Ʋ䌁皦ᮔǅ༬皧煞क़Ѐ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠ƲبǜV /펔B䌁皦 ᮔǅ'鱤ǆၜ먢䇨珵呈ᠾ뤂ᐱ⿇⬿먲僧ᐱ㥲ᐲ�僬㣢ᐲᠾ랖僧Ҵ識�僬㣢ᐲ臆S㥲ᐲᬄğ識理艏S杴識杴㥲ᐲ

06/14/2020

Why does the refrigeration compressor frost and the solution!

Why does the refrigeration compressor frost and the solution! 1. The frost on the compressor return air port indicates that the temperature of the compressor return air is too low, so what will cause the compressor return air temperature to be too low? 器2䀀ￜ皥䖒皦즠Ʋ嫜ི㲈Ʋ䌁皦ᮔǅ༬皧嫦ིЀ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠ƲبǜV /펔B䌁皦 ᮔǅ'鱤ǆၜ먢䇨珵呈ᠾ뤂ᐱ⿇⬿먲僧ᐱ㥲ᐲ�僬㣢ᐲᠾ랖僧ӄ識�僬㣢ᐲ臆S㥲ᐲᬄğ識理艏S杴識杴㥲ᐲ

06/14/2020

Basic knowledge of refrigeration compressors! Did you know everything

Basic knowledge of refrigeration compressors! Did you know everything Why should the compressor run continuously for at least 5 minutes, and stop at least 3 minutes after shutdown to restart? Stop at least 3 minutes after shutting down to start again 器2䀀ￜ皥䖒皦즠Ʋ煔क़㲈Ʋ䌁皦ᮔǅ༬皧煞क़Ѐ呄ᠾ鹨់༹皧ࠄ00령ꐱ댁珵뛐珵Љ䕄ྦ뤂ᐱ뚜珵ᴴᏩ呄ᠾ퍘ᒥ鹨់ᩄꋔྦ瑉浥巠皱㙲皦抐皱巠皱੨皦柘皱ￜ皥ب巠皱㙲皦忈皱੨皦柘皱즠Ʋǜ勁皦즠ƲبǜV /펔B䌁皦 ᮔǅ'鱤ǆၜ먢䇨珵呈ᠾ뤂ᐱ⿇⬿먲僧ᐱ㥲ᐲ�僬㣢ᐲᠾ랖僧і識�僬㣢