Daikin VRV-WIII Installation Manual

Contents

9 English9. REFRIGERANT PIPINGCautionAfter completing installation, be sure to open the valve.(See 9-9 Additional refrigerant charge for details) (Operatingthe unit with the valve shut will break the compressor.)Use R410A to add refrigerant.All field piping must be installed by a licensed refrigeration techni-cian and must comply with relevant local and national regulations.CAUTION TO BE TAKEN WHEN BRAZING REFRIGERANTPIPINGDo not use flux when brazing copper-to copper refrigerant pip-ing. (Particularly for the HFC refrigerant piping) Therefore, usethe phosphor copper brazing filler metal (BCuP-2: JIS Z 3264,B-Cu93P-710/795: ISO 3677) which does not require flux.(Flux has extremely harmful influence on refrigerant piping sys-tems. For instance, if the chlorine based flux is used, it will causepipe corrosion or, in particular, if the flux contains fluorine, it willdamage the refrigerant oil.)Note• Installation tools:Gauge manifold, charge hose, etc.Make sure to use installation tools that are exclusively used forR410A installations to withstand the pressure and to preventforeign materials (e.g. mineral oils such as SUNISO and mois-ture) from mixing into the system.(The screw specifications differ for R410A and R407C.)Vacuum pump1. Use a 2-stage vacuum pump with a non-return valve.2. Make sure the pump oil does not flow oppositely into the sys-tem while the pump is not working.3. Use a vacuum pump which can evacuate to –100.7 kPa (5Torr,–755mmHg).9-1 Selection of piping material1. Foreign materials inside pipes (including oils for fabrication) mustbe 30mg/10m or less.2. Use the following items for the refrigerant piping.Material : Jointless phosphor-deoxidized copper pipeSize : See “Example of connection” to determine the correctsize.Thickness : Select a thickness for the refrigerant piping whichcomplies with national and local laws.For R410A, the design pressure is 4.0 MPa (40-bar).The minimum thickness of piping according to Japan’s High-Pressure Gas Safety Law (as of January 2003) is shownbelow.Temper grade (O type, 1/2H type) in the table indicate thematerial types specified in JIS H 3300.(unit : mm)(unit : mm)3. Make sure to use the particular branches of piping that have beenselected referring to chapter “Example of connection”.4. Refer to chapter “Shutoff valve operation procedure” in 9-10 aboutthe shutoff valve operation procedure.5. Make sure to perform the piping installation within the range of themaximum allowable pipe length, allowable level difference andallowable length after branching as indicated in chapter “Exampleof connection”6. For installation of the refrigerant branching kit, refer to the instal-lation manual delivered with the kit.And follow the conditions listed below.• Mount the REFNET joint so that it branches either horizontallyor vertically.• Mount the REFNET header so that it branches horizontally.(Refer to figure 22)1. Horizontal surface2. With in 30° against horizontal surface3. Horizontal surface7. The outside unit multi connection piping kit that is sold separatelyas an option (BHFP22MA56·84, BHFP26MA56·84) is necessaryfor the multi installation of outside units. See the installation man-ual attached to the kit with attention to the following restrictionswhen installing.Restriction for the installation of the outside unit multi connec-tion piping kit• Install the joint horizontally within a lean of ±15°with cautionnameplate on top. Refer to figure 23 (Fig. A)Do not connect it vertically. Refer to figure 23 (Fig. B)• Reserve the straight part of 500mm or more to the branch pipeand do not bend the local pipe in that area.Straight part of 500mmor more can be reserved if a local pipe (straight pipe) of 120mm ormore is connected to the joint. Refer to figure 23 (Fig. C)• Incorrect installation may cause breakage of outside unit.(Refer to figure 23)1. Caution nameplate2. Horizontal line3. Ground4. Straight part of 500mm or more5. Local pipe(120mm length or more)9-2 Protection against contamination wheninstalling pipes• Take measures to prevent foreign materials like moisture andcontamination from mixing into the system.• Great caution is needed when passing copper tubes throughwalls.9-3 Pipe connection• Only use the flare nuts included with the unit.Using different flare nuts may cause the refrigerant to leak.• Be sure to perform a nitrogen blow when brazing.(Brazing without performing nitrogen replacement or releasingnitrogen into the piping will create large quantities of oxidizedfilm on the inside of the pipes, adversely affecting valves andcompressors in the refrigerating system and preventing nor-mal operation.)CautionDo not use anti-oxidants when brazing the pipe joints.Residue can clog pipes and break equipment.Note• For nitrogen replacement method,see the “Installation Manual” (contact your dealer).• The pressure regulator for the nitrogen released when doing thebrazing should be set to 0.02 MPa(0.2kg/cm 2) or less.(Refer to figure 18)1. Refrigerant pipe2. Location to be brazed3. Nitrogen4. Taping5. Manual valve6. RegulatorPrecautions when connecting pipes• See the following table for flare part machining dimensions.• When connecting the flare nuts, apply refrigerant oil to the insideand outside of the flares and screw them in by hand three or fourtimes at first.(Use ester oil or ether oil.)• See the following table for tightening torque.(Applying too much torque may cause the flares to crack.)• After all the piping has been connected, check the gas leak withnitrogen.Temper grade O typeouter diameter φ6.4 φ9.5 φ12.7 φ15.9smallest thickness 0.80 0.80 0.80 0.99Temper grade 1/2H typeouter diameter φ19.1 φ22.2 φ25.4 φ28.6 φ31.8 φ34.9 φ38.1 φ41.3smallest thickness 0.80 0.80 0.88 0.99 1.10 1.21 1.32 1.43Place Installation period Protection methodOutdoor More than a month Pinch the pipeLess than a monthPinch or tape the pipeIndoor Regardless of theperiodpipe size tighteningtorque (N · m) A (mm) flare shapeφ9.5 32.7 - 39.9 12.8 - 13.2φ12.7 49.5 - 60.3 16.2 - 16.6φ15.9 61.8 - 75.4 19.3 - 19.7R=0.4~0.845˚±290˚±2A