The most comprehensive inverter multi -connected project installation explanation


The most comprehensive inverter multi -connected project installation explanation

The main steps for the installation of frequency frequency multi -connected project:

1. Material preparation

2. Preparation before installation


3. Equipment installation

4. Cold media pipe construction construction

5. Concrete water pipe construction

6. Construction of power distribution and communication system

7. Qi Test

8. Vacuum drying

9. Refrigerator filling


10. System debugging

From Nuantong South Society (Qi Nan Society) carefully organized and published for you.

1. Material preparation


The current variable frequency multi -connected market generally uses R410A refrigerant. Requirements for refrigerant pipe materials:


Material: seamless copper tube, pull -up. When entering the venue, you should have a factor certificate and test report. The inner and outer surface of the pipeline should have no pinch, cracks, peeling, foaming, mixed, copper powder, carbon accumulation, green rust, dirty and severe oxide film, and no obvious scratches, pit, spots, etc. defect.

The minimum copper tube wall thickness requirements (see the table below)

R410A refrigerant pipe wall thickness requirements table:

Pipe outer diameter (MM)









Minimum wall thickness (MM)

















Both ends of the pipeline must be sealed.

Differential pipes: Dedicated U -shaped pipes.

Insulation material: The heating material should be used with closed -hole foaming materials, which is difficult to ignite B1, and the heating resistance exceeds 120 ° C; when the outer diameter of the copper pipe is d≤ ¢ 12.7mm, the thickness of the insulation layer is more than 15mm, and the outer diameter of the copper pipe is D ¢ ¢ ¢ ¢ ¢ ¢ ¢ ¢ At 15.9mm, the thickness of the insulation layer is more than 20mm, and the thickness of the insulation layer of the outer diameter of the copper pipe is φ = 25mm or more.

Signal line: The signal line must be shielded with ≥0.75 square meters.


Both ends of the pipe must be sealed to prevent the copper tube from being damaged due to collision.

Cleanness requirements: impurities <30 mg/10m.


Mineral oil and R410A are not dissolved, and pipelines will cause dirty pipelines.

Water and oxide residues can also cause ice and dirt.


2. Preparation before installation


1. Check the model and quantity

2. Check the intact of packaging and appearance

3. Confirm the installation of attachments and accessories

Construction Conditions

1. Carefully read random attachment installation instructions

2. Power supply power supply capacity and voltage

3. Outdoor foundation

4. Reserve holes and embedded parts

5. Equipment handling channel

Materials: specifications, technical requirements and quantity

Installation tool requirements

Drawing Mixed

The majors of the construction of the construction at the same time exist in the construction drawings at the same time: the elevation? The location of the equipment and pipeline? The order of construction? Interference between various majors? ……and many more.

Installation process:

Third, equipment installation

Pain points for outdoor installation:

1. The crew and the foundation shall be installed or vibration pads in accordance with the design regulations.

2. The contact between the outdoor machine and the foundation should be tight, otherwise it will produce a large vibration and noise.

3. The body itself must have a reliable ground.

4. Before debugging, it is forbidden to open the valve of the outdoor gas and liquid tube.

5. The installation location must ensure that there is enough maintenance space.

Wall -mounted basic precautions:

Basic intensity: load -bearing satisfaction requirements;

Multiple wall hanging foundations at the same time;

The strength of the wall: there is enough strength to load the weight of the machine;

The use of expansion bolts is prohibited, the pairing bolt must be used;

Be sure to use steel pads on the wall;

Basic rust -proof and anticorrosive treatment.

Pain points for indoor machine installation:

Installation steps: OK Installation Location → Planning Labeling position → Playing expansion bolts → Hanging indoor machine

1. The installation of the indoor machine must be flattened, and the level is kept within ± 1 °, reducing noise during operation, and avoiding condensate water from overflowing from the water disk.

2. The suspension boil must be able to withstand the weight of the indoor machine. If the length of the boom exceeds 1.5m, the triangle is fixed or four booms, and two nuts are used to fix the indoor machine. To prevent loosening, apply a thread locking solid agent in the boom and nut. Ensure that the unit’s operation will not cause abnormal vibration and noise.

3. Maintain enough maintenance space, reserve the inspection and repairs of the repairs is 450X450mm or more;

4. Indoor machines ensure that there is a suitable installation space for condensed drainage pipes.

5. The indoor machine and the ceiling are tightly matched, and the distance from the top is 600mm. The inner machine cannot be in contact with other material.

The ceiling of the embedded machine: 860mm ~ 910mm, it is recommended to 890mm × 890mm;

Requires the level of indoor machine or allowing the side of the drain pipe to be slightly lower of 1 to 5mm;

When the decorative panel is installed, the part of the panel is marked with the “refrigerant pipe” direction. The part of the indoor machine is consistent with the refrigerant pipe interface of the indoor machine, and the panel and the indoor machine are seamless.


The minimum distance from the top of the indoor machine to the floor is 10mm.


6. It should be ensured that the delivery and return air are smooth to prevent the air flow from short circuit.


7. The indoor machine must be cleaned after the lifting of the machine to avoid the smell and dust from entering the interior machine during the decoration, which causes the first chance to start with odor and dust. At the same time, the dust accumulates on the indoor machine heat exchange, which will affect the heat exchange effect.

8. The indoor machine hanging must be fixed with a double nut at the lower end of the screw to ensure that the indoor machine is solid firmly; if the single nut is fixed, it will cause the indoor machine to loosen during the operation, cause noise or cause other faults.

9. To ensure that the gap between the machine’s air supply is high, it meets the requirements.

Interior protection:

When carrying or lifting the indoor machine, it is not allowed to grab its resin housing, or to destroy the insulating material on the surface of the machine.


Before the indoor machine is installed, the packaging shall not be removed.

Protection measures during indoor machines: Prevent the insulation layer of indoor machines.

After the installation is completed, the inner machine should be bandaged and protected with a plastic bag before the decoration is completed.

To prevent short circuit of air flow.

The air ducts and maintenance ports meet the installation requirements (leaving full inspection and repairs, generally 450x450mm).

Other related details:

Indoor fixation

Dual nuts must be fixed at the lower end of the screw to ensure the firmness of the indoor machine. If a single snail is fixed, it will cause the indoor machine to loosen during the operation, cause noise or cause other faults.

Indoor leveling

⑴ After the indoor machine is fixed, the horizontal ruler should be flattened (keep within ± 1 °).

必须 The installation of indoor machines must ensure the level to reduce operating noise.

(3) The installation of the indoor machine must ensure the level, and avoid condensation water from overflowing from the water disk.

时 When installing the indoor machine, you should pay attention to reserving sufficient maintenance space on both sides.

Fourth, refrigerant pipe construction construction

See the table three principles below:

Cause of problems

Countermeasures to prevent failure



No water inside

External rainwater entry/engineering water entry/tube produces condensate water

Cover the pipe, blow washing, vacuum drying



Oxide formation in the welding process

Tong nitrogen protection during welding


During welding, oxides, external dust, and debris entering in the tube enter

Payment processing process Pay attention to clean protection


No refrigerant leak

Welding is not tightly welded/unqualified sealing of the speaker mouth/edge leakage

Use suitable materials and strictly abide by the welding operation procedures

Airtight test

Strictly abide by the rules of pipeline expansion operation


Strictly adhere to the interface operation regulations

Points for installation of differences:

1. Differential tubes cannot be replaced with three links.

2. The model and connection must be confirmed in accordance with the construction drawings and installation instructions

The pipeline of the supervisor and the support.

3. The distance between 500mm before and after the divergence component cannot be set within a distance of 500mm (90 ° bending angle).

4. Try to make the installation location of the spinach components in a place that is convenient for welding (if there is no guarantee, the prefabricated component can be prefabricated first).

5. Horizontal or vertical installation, the horizontal angle should be within 10 ° angle.


6. In order to ensure that the refrigerant is evenly diverted, the installation of differential tube components should pay attention to the distance of its horizontal pipeline.

1. Before the copper pipe is used, it must be cleaned

the cleaning method:

Silk cloth washing: Wrapped a clean silk cloth with fine steel wire, the silk cloth wrapped into a ball, and the diameter of the cloth group was slightly greater than the diameter of the copper pipe. When cleaning, drip some trichlorndue preparations on the silk, enter from one end of the copper pipe, and then pull out from the other end. Every time, the cloth group is immersed with trichloroethylene to wash off the dust and impurities on the silk cloth. Repeated cleaning until there is no dust and impurities in the tube. ——The applicable to direct tube.

Blow: Use nitrogen or dry air to blow off the dust and foreign objects in the tube. —— Applicable to the pipe

Nitrogen pressure: 5 to 6kgf/cm2


1) After the cleaning is completed, the copper pipe end should be blocked in time with a cover or tape.

2) If it is not connected for a long time, the seal should be welded.

2. Pipe cutting and cutting burrs


You must use a tube cutter, you cannot use a saw and a shot machine;


Rotate the knife clockwise, rotate the knife adjustment device of the cutting knife, and gradually get into the knife.



After cutting, polish, remove the inner wool thorns, pay attention to the pipes down to prevent the powder from entering the tube.


If the burr is not completely removed, the phenomenon of air leakage will occur at the expansion part, so the burrs should be removed carefully.

3. Tube bending pipe: can reduce the welding point

processing methods:

A. Manual bending tube-suitable for fine copper pipes (φ6.35-φ12.7)

B. Mechanical bending pipe-wide applicable range (φ6.35-φ44.45)


Processing requirements:

The bending radius of the pipeline bending pipe should be greater than 3.5D (D is the diameter of the pipe), and the ratio of the short diameter to the original diameter after the bending deformation of the pipe should be greater than 2/3.

1) During bending processing, the inside of the copper tube cannot be wrinkled or deformable;

2) The welding interface of the pipeline should not be placed in the bending area, and the distance between the bending part of the tube or the parts of the interface should not be less than 100mm.

4. Expansion operation


The main points of the operation:


1) Ensure that the end surface of the copper pipe is flat;

2) Clear the burrs and edges inside the mouth;

3) Put the expansion nut on the pipeline before expanding the expansion;

4) Expansion should be the same diameter as the parent tube, and must not be eccentric;

5) Put the copper pipe in the root of the tube expansion;


6) Nonth cracks should not be generated.

If the R22 refrigerant pipe is used with a expansion, the R410A refrigerant copper pipe should be processed as shown in the figure on the right.

A size is 1mm to 1.5mm, please pay attention.

Piping diameter






Expansion outer diameter size


~ 8.8



~ 12.8


~ 16.2


~ 19.4



~ 23.7

Expansion connection steps

5. Self -inflation tube operation

Used to connect the tube welding between copper pipes; use the pipe expansion to process.

6. Pipeline connection

1) Inserting 钎 welding connection

Suitable for connections between pipeline and pipelines, pipelines and pipes.

Do not be too large or too small between the gaps between the inheritance, ensure that the friction is not fell without falling.


The expansion direction of the inheritance should welcome the medium.

2) Inserting 钎 welding connection


Packing : welding: The socket welding is actually another form of inheriting the welding welding, that is, the method of using a tube or a large type of pipe for welding. The depth of its insertion should not be less than the provisions of the inheritance connection.


3) Pipeline connection -flange connection

Flange connection: The copper pipe and equipment of the larger pipe diameter usually use flange connection when connecting. The surface of the flange should be cleaned without damage. Use the air -conditioning machine to apply the flange surface and install it. Two flange plates should be positive, and the diagonal direction is fastened to prevent sink.


7. Sealing operation

Sealing: It is an important operation that can prevent water, dirt or dust from entering, and prevent others from damaging.

The first is to wrap the tape: use the PVC tape to seal the end of the copper tube.

The second is to shrink: squeeze the end of the copper tube together, and then welded the gap.

8. Welding operation

assignment order:

Clean the welding site;

Confirm whether the gap between the tube and the joint is appropriate;

Blow with inert gas (nitrogen replacement welding), nitrogen pressure is 0.02 mPa, and nitrogen is charged before welding. After the welding is completed, the nitrogen tube is completely cooled before the nitrogen is turned off.


Preheat the welding.

Note: When welding, please use welded materials and welded additives that do not need welded additives. Recommended Use:

Phosphorus and copper welding material, 温 welding temperature 735-840 ℃


Silver copper welding material, 度 welding temperature 700-845 ℃

No nitrogen welding, black copper oxide in the copper pipe, and after running, it will block the filter filter, electronic expansion valve, and oil return component.

Important precautions for welding operations:


1) Using hard tadpole welding, 2%silver welding stick containing silver. The temperature is 700 to 845 degrees.

2) It must be protected by nitrogen. The flow of nitrogen is not less than 0.02 ~ 0.05m3/h, or the diameter of the copper tube is not the same. Require. Before welding, you must remove the air in the tube clean! Intersection

3) After welding, continue to pass nitrogen for 3 to 5 minutes until no oxidation occurs.

4) After the welding is completed, the surface of the copper tube cannot be used to cool the copper tube (the contraction rate of copper and welding material is different, the stress concentration, and the crack is generated).

5) After welding, the inner wall of the copper tube should have no oxide.

Welds: no sandylona, ​​bubbles, full and smooth.

Strictly prohibit supper welding.

6) The temperature of the mother material (copper tube) must be melted, instead of melting directly by the flame.

7) Safety awareness! Safety measures! Welding personnel must have an qualification certificate! Fire application!

9. Installation of divergence

1) The differences are as close to the indoor machine as much as possible;


2) Differential pipes must be matched with the equipment, and products are not allowed to use equipment manufacturers;

3) Before installation, you must check the model of the divert, and you must not use it wrong;

4) The liquid pipe and the trachea should have the same tube length, and the lines are paved with the same lines and parallel laying;

5) The length of the straight pipe section between the two adjacent ducts must not be less than 500mm;

6) The outbound and entrance side of the joint and end tube requires a direct tube of more than 500mm. Otherwise, it is easy to cause refrigerant partial flow and refrigerant liquidity.

7) Installation method

A. Horizontal installation

The three ports are required to be on the same horizontal plane, and the stereotype size and assembly angle of the differences must not be changed;

B. Vertical installation


You can go up or down to ensure that the three ports are on one vertical facade, but not allowed to be skewed;


Correct case

Error case

10. Fixed piping


The pipe is fixed with corner steel brackets, brackets or round steel suspensions. The “U” tube or flat steel is fixed outside the thermal insulation layer. In principle, the insulation material is not allowed to compress to ensure its effect.

The horizontal tube is fixed: oblique corner steel brackets, inverted “T” or “L” -shaped corner steel brackets or round steel suspension can be used. Corner steel uses a 30 × 30 × 3mm equivalent steel, and the diameter of the round steel is φ8mm.


Pipe outer diameter (MM)

Minimum wall thickness (MM)













Range fixation: The tube card should be used instead of the thermal insulation material, and the “U” tube card should be fixed outside the round wood. Round wood should be anticorrosive.

The production of branches, hanging, and brackets should be required to be load -bearing, and rust removal and anticorrosive treatment before installation.

Seeing the minimum spacing between the refrigerant pipes, the minimum spacing between the risers, and the brackets, see the table below:

Pipeline outer diameter (MM)



20 ~ 40



The spacing of the horizontal pipe (M)




Story spacing (M)




1) The fixing of the refrigerant trunk and supporting pipes must be used. The U -shaped card must be used. The bandaging belt cannot be tied and fixed to the horizontal tube and vertical vertical pipe, and the local supporting tube fixation (the fixation of the divert, around the interior machine, before and after the wall). The trachea and liquid tube are separated! Intersection Can’t be tied together to fix! Intersection

2) Copper pipes, water pipes, and communication lines are not allowed to wear the same wall hole, and the sleeve must be installed separately.

3) The U -shaped card used in the copper tube in the well should be made of flat steel when fixed. The copper tube cannot be contacted directly with the suspension, and the thermal insulation layer must be padded in the middle. Or other fixed methods.

4) Anti -rust and anticorrosive racks! Intersection The first is to apply red rust paint twice, and then brush the silver powder on the surface.

5) The tube card should be used instead of the insulation material, and the “U” shaped tube card is fixed outside the round wood. Round wood should be anticorrosive.

11. Local support and fixation


1) Local support

2) Local fixation

11. Back to the oil back (HVAC has talked about it)

When the outdoor unit is on the indoor machine, on the vertical trachea between the outdoor and the indoor machine, the oil back of the oil is increased by 10 meters more than 10 meters.

The height of the oil back bend is generally around 10cm. Or 3 to 5 times the outer diameter of the copper tube.

12. Pipe tube insulation construction


The insulation material uses rubber and plastic foam insulation pipes, which is difficult to ignite, and its heat resistance is 120 degrees;

The thickness of the insulation layer:

1) When diameter ≥15.88mm, the thickness of the insulation material is 20mm;

2) When diameter ≤12.7mm, the thickness of the insulation material is 15mm;

The insulation of outdoor copper pipes: For the system used in the northern region for winter heating, the insulation wall is thick and thicker, generally 40mm. For the insulation of the trachea of ​​the indoor part, it is best to do not distinguish between the tube. The thickness of the tracheal insulation wall is 20mm.

The cohesion of the thermal insulation pipe should be adhesive and the tape should be used, and then the tape of the electrical workers should be used. The width of the tape should not be less than 50mm to ensure that the thermal insulation between the solid copper pipe and the indoor machine should be tightly prevents the generation of condensate.

Pipe-mounted insulation construction-insulation construction of indoor machine connection parts

Please follow the key to the refrigerant of the indoor machine, and do a good job of thermal insulation project

Preservation method

Cutting off site repair

First of all, cut the warm insulation material longer than the gap, open the two ports, embed the heating material, and closely paste the glue at the interface. The surface is wrapped with a tape (be careful not to be too tight, avoid excessive squeezing warming material, resulting in the lack of thermal insulation effect) Essence

Error case

13. The main points of storage and maintenance of copper pipes:

1. The copper pipe is sent to the construction site. Whether it is straight or the pipe, be careful not to deform or bend. The two ports must be blocked with a lid.

2. When the pipe is installed and connected, if it cannot be connected to the room and the machine in time, a seal must be performed.

3. During the construction of the pipe tube, the port must be wrapped well. (Especially when wearing a thermal set, when wearing a wall)

Incorrect case: The two ends must be sealed before the use of copper pipes

14. Electronic expansion valve installation

安 Electronic throttling components should be installed vertically and upward, and it is forbidden to tilt and invert.

与 When the electronic chip part is connected to the indoor and outdoor machine pipes, the two wrenches should be operated to prevent the copper tube cracking.

(3) Swipe components cannot be connected by oxygen welding.

接 Please pay attention to the connection direction when connecting (see the sticker on the electronic throttling component).


Fifth, condense water pipe construction construction

Water pipe material

Give water for PVC plastic tube, (the pressure resistance is not less than 9kgf/cm2). Its specifications and wall thickness are: UPVC pipe: φ32 × 2, φ40 × 2, φ50 × 2.52

Hot -galvanized steel pipe: φ25, φ32, φ40, φ50.

Principles of the installation of drainage pipes:

理 Diagram 径 Pipe diameter A reasonable ⑵ Emissions nearby

Installation points:

⑴ The drainage pipe is less than 1/100.

According to the length of the pipe section, it can generally be between 5 ‰ and 5%, or the local slope can be greater;

Can’t fall down;

The exit of the drainage outlet without a drainage pump without a drainage pump is not less than 1%.

避 Horizontal drainage pipes must avoid hedging phenomena to avoid falling slopes and poor drainage.

(3) The highest point of the drainage pipe should be set up to ensure that the condensation water is discharged smoothly, and the exhaust port must be facing down to prevent the dirt from entering the pipeline.

, After the pipeline connection is completed, the water traffic test and full water test should be performed. On the one hand, check whether the drainage is smooth, and on the other hand, check whether the pipe system is leaking.


缝 At the seam of the insulation material, it must be adhesive with a dedicated adhesion, and then the rubber plastic tape is wrapped. The width of the rubber and plastic band is not small to ensure firmness and prevent condensation.


必须 The air -conditioning machine drainage pipe must be installed separately with other sewage pipes, rainwater pipes, and drainage pipes in the building.

Indoor machines in different drainage forms cannot shared the same episode drainage pipe.

: The spacing of the hanging frame: usually 0.8m-1m in the horizontal tube and 1.2m-1.5m riser. Each riser must not be less than two.

、 The static pressure value is relatively large, and the indoor machine of the natural drainage must be used to save water.


Important details


1) Skill rack installation

The spacing of the hanging frame: usually 0.8m-1m in the horizontal tube, 1.2m-1.5m riser, and each vertical tube must not be less than two. After forming a gas bag, no matter how drainage can only compress the gas bag without drainage, causing drainage abnormalities.

2) Drainage pipe installation method

No condensed water increase pump model

There are condensation water to improve the pump model



Then, then, then

Construction of power distribution and communication system

Points for strong electricity layout:

When applying the line, according to the requirements, different colors of wires should be used for phase lines, zero lines, and protection ground (zero) lines;

The signal cable between the power cord and the indoor unit of the concealed project must be separated by the wires separately; if it is parallel to arrange, and the signal line and the power cord should be at least 300mm.

Electric installation attention points:


The power cord connection must use the pressure line terminal.

线 The indoor signal line must adopt the connection method and strictly prohibited connection method; the inner and outer machine connection cable must be used to use the three -core shielding line, the indoor machine is only connected to the signal line, and its shielding layer is short. , The last one is cut off directly, the shielding layer must be connected to the sheet metal when the communication line to the outdoor unit.

(3) When the power cord and the signal cable are parallel, put the wires into their respective wire tubes, and there must be a suitable wire spacing distance (the current capacity of the power cord: below 10A -300mm, below 50A -500mm).

足 The current capacity must be sufficient, the cable line diameter must meet the requirements, and the leakage protection switch must be installed.

必须 Outdoor ground ground must be reliable. (Note: The grounding line cannot be connected to the pipelines, gas pipes, and fire management pipelines.)


机 Multi -connected indoor machines must be powered uniformly.


The signal line must use the three -core barrier line (0.75m2)

All signal cables are polar and cannot be mistaken, otherwise there will be a traffic failure.

Error connection:

Seven, Qi Tan Test

1) Key points: Guarantee that the gas pressure within 24 hours is kept at 4.15MPa

2) Purpose: Verify the pipe distribution system without leakage;

3) Test steps: Press the system liquid pipe and trachea at the same time with nitrogen








More than minutes

You can find a big leak



You can find a large leakage


twenty four


You can find a small leak

Note: Nitrogen pressure changes with the environmental temperature, and there will be a pressure change of+0.01MPa every+1 ° C (when this standard is tested when mixed with water or other gases). Make records so as to compare temperature changes to correct.

To prevent the equipment from damaging, the pressure keeping time should not be too long! Intersection

Discovery method:

Check the method of leakage can be checked by feel, listening, soapy water, or put nitrogen to 0.3MPa (3kgf/cm2) after the nitrogen test pressure is completed, and the corresponding refrigerant is added to 0.5MPa (5kgf/cm2 ) Use the leak detector that is compatible with the refrigerant.

Precautions for pressure testing


Pressure correction: Temperature change 1 degree pressure corresponds to 0.1kg.

At the same time from the trachea and liquid tube nitrogen filling

The range of the pressure gauge: R410A — 4.5MPa or above;

The pressure should rise slowly when pressing pressure;


Before test pressure, you must check the trimmed valve of the trachea and liquid tube to prevent nitrogen from entering the machine system during test pressure.

If the pipe is temporarily put on hold after the pressure test is completed, it is best to use the vacuum in the piping, and then use nitrogen pressure to prevent water from entering the pipe.

You can do the pressure test multiple times: the first time the pipe system is performed to test the sealing of the welded joint; after the second time the indoor and outdoor unit is connected, the sealing of the expansion nut and flange connection are tested.

If you need to keep pressure for a long time, the pressure should be reduced to less than 0.5MPa (5kgf/cm2). Long -term high pressure may cause leakage in the welding site and there are hidden safety hazards.

Eight, vacuum dry

1) Points: Use vacuum pumps with a vacuum below -755mmHg and an exhaust volume of 40L/min above

2) Objective: remove the water in the system;

3) The outdoor unit does not smoke the vacuum. Do not open the interception valve on the side of the outdoor unit and the side of the liquid;


4) Confirm that the vacuum pump works can reach -755mmHg below 2 hours; if it is still less than -755mmHg if it is more than 3 hours, it means that there is a mix of water mixing or leakage, and it needs to be checked;

Tool points: Use a new refrigerant-specific vacuum pump (with a stop valve) or install the deeper valve on the original vacuum pump. The vacuum pump below -755mmHg is below -755mmHg.

Vacuum drying operation steps

1) Unprecedentedness, confirm that the air and liquid tube cut -off valve is closed again.

2) Connect the regulatory valve and vacuum pump on the detection joint of the air valve and liquid valve with the filling catheter.

3) Pump for 2 hours until the vacuum reaches 756mmHg or above. If the vacuum cannot reach 756mmHg, there may be leaks. It should be performed again. If there is still no leakage, it should be vacuum for another 1.5-2 hours.

4) If the vacuum is not kept in vacuum twice, it is determined that the pipes contain water under the condition of no leakage. At this time, water destruction should be taken to discharge water. The specific method is to fill the nitrogen of 0.05MPa in the pipeline. If you still reach 756mmHg, repeat this operation until the water is exhausted.

5) After the vacuum is pumped, turn off the valve of the regulating valve, stop the vacuum and keep it for 1 hour. The pressure of the regulating valve has not increased.

At the same time, the trachea and liquid tube are vacuum.

When closing the vacuum pump to stop the vacuum, the valve should be turned off first, and then the vacuum pump is broken.


For 1 hour, the pressure of confirmation of the vacuum table has not been picked up to qualify.


For the new refrigerant R407C and R410A systems, dedicated tools and instruments should be used in the position of direct contact with refrigerants.

Nine, refrigerant filling

Cold media filling steps

1) Calculate the addition of refrigerant, record the pipeline system and the indoor machine rechargeable amount in the random table, and put the form on the panel of the outdoor electromechanical box. This will be convenient for future maintenance.

2) Put the charging tank on the weighing, write down the reading, and calculate the reading after the refrigerant is completed. Excessive or insufficient refrigerant will cause serious damage to the unit.

3) Use the rechargeable catheter to bring the double -head pressure meter and the charging tank with the regulating valve to receive the detection joint of the air valve and liquid valve. Before the connection, release a part of the refrigerant and discharge the air in the pipe.

4) Confirm that the outdoor gas and the liquid tube cut -off valve are in a close state.

5) Open the charging tank to adjust the valve valve without booting.

6) Observe the number of readings that focus on, turn off the adjustment valve immediately after the requirements are required, and then turn off the valve of the charging tank. If a bottle of refrigerant is charged or more, the readings of each charging tank should be recorded.

Confirm the construction, wiring construction, air tight test, and vacuum dry

The specifications and length calculations of the system should be accurate to ensure that the accurate filling volume is calculated.


The additional refrigeration dose measurement should be accurate, and the weight must meet a certain accuracy to ensure that the error is within a reasonable range.

When adding a refrigerant, in order to prevent liquid strikes, it is necessary to prevent excessive additional additional operations, and must confirm whether there is a rainbow suction device in the cylinder to ensure the addition of R410A refrigerant in the liquid state

The R410A is a non -common boiling mixed work. The composition of the gas phase and the liquid phase must be added.


There must be a siphon device must adopt a steel cylinder to stand up

The siphon -free device must be inverted in the cylinder

In the process of additional, the actual addition and filling in the refrigerator charging form pasted on the outdoor unit should be facilitated for later maintenance and use.

10. System debugging


Dial switch settings

Outdoor dial switch

Wired remote control

Debugging method 1: Trial transportation through the outdoor unit (see the product instructions of various manufacturers)


Debugging method 2: Through the wired remote control, conduct trial transportation (see the product instructions of various manufacturers)


Setting method steps

1. Press the “operation switch” and “check” keys for more than 3 seconds, and the “trial operation” is displayed on the bottom right side of the wired remote control.

2. Select the trial transport mode “cooling” or “heating”

3. Set the air volume to the “high wind” state

4. Press “Run/Stop” key

1. All wired remote controls in the same system must be set according to the above method

2. Automatically end the trial operation for 2 hours, stop the trial operation in the middle, press the “Run/Stop” key

3. Confirm whether the number of indoor machines that show is consistent with the actual connection

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