Toshiba RAS-07BKV-E Installation Manual

Also see for RAS-07BAV-E: Installation manual Service manual Owner's manual Owner's manual

12APPENDIXAPPENDIXWork instructionsThe existing R22 and R407C piping can be reused forinverter R410A product installations.WARNINGConfirming the existence of scratches or dents onthe existing pipes and confirming the reliability ofthe pipe strength are conventionally referred to thelocal site.If the specified conditions can be cleared, it ispossible to update existing R22 and R407C pipesto those for R410A models.Basic conditions needed to reuse existingpipesCheck and observe the presence of three conditions inthe refrigerant piping works.1. Dry (There is no moisture inside of the pipes.)2. Clean (There is no dust inside of the pipes.)3. Tight (There are no refrigerant leaks.)Restrictions for use of existing pipesIn the following cases, the existing pipes shouldnot be reused as they are. Clean the existing pipesor exchange them with new pipes.1. When a scratch or dent is heavy, be sure to use newpipes for the refrigerant piping works.2. When the existing pipe thickness is thinner than thespecified “Pipe diameter and thickness,” be sure touse new pipes for the refrigerant piping works.y The operating pressure of R410A is high (1.6 timesthat of R22 and R407C). If there is a scratch or denton the pipe or a thinner pipe is used, the pressurestrength may be inadequate, which may cause thepipe to break in the worst case.* Pipe diameter and thickness (mm)Pipe outer diameter Ø6.4 Ø9.5 Ø12.7Thickness R410A 0.8 0.8 0.8R22 (R407C)y In case the pipe diameter is Ø12.7 mm or less andthe thickness is less than 0.7 mm, be sure to use newpipes for the refrigerant piping works.3. When the outdoor unit was left with the pipesdisconnected, or the gas leaked from the pipes andthe pipes were not repaired and refilled.y There is the possibility of rain water or air, includingmoisture, entering the pipe.4. When refrigerant cannot be recovered using arefrigerant recovery unit.y There is the possibility that a large quantity of dirtyoil or moisture remains inside the pipes.5. When a commercially available dryer is attached to theexisting pipes.y There is the possibility that copper green rust hasbeen generated.6. When the existing air conditioner is removed afterrefrigerant has been recovered.Check if the oil is judged to be clearly different fromnormal oil.y The refrigerator oil is copper rust green in color:There is the possibility that moisture has mixed withthe oil and rust has been generated inside the pipe.y There is discolored oil, a large quantity of residue,or a bad smell.y A large quantity of shiny metal dust or other wearresidue can be seen in the refrigerant oil.7. When the air conditioner has a history of thecompressor failing and being replaced.y When discolored oil, a large quantity of residue,shiny metal dust, or other wear residue or mixture offoreign matter is observed, trouble will occur.8. When temporary installation and removal of the airconditioner are repeated such as when leased etc.9. If the type of refrigerator oil of the existing airconditioner is other than the following oil (Mineral oil),Suniso, Freol-S, MS (Synthetic oil), alkyl benzene(HAB, Barrel-freeze), ester series, PVE only of etherseries.y The winding-insulation of the compressor maydeteriorate.NOTEThe above descriptions are results have been confirmedby our company and represent our views on our airconditioners, but do not guarantee the use of the existingpipes of air conditioners that have adopted R410A inother companies.Curing of pipesWhen removing and opening the indoor or outdoor unit fora long time, cure the pipes as follows:y Otherwise rust may be generated when moisture orforeign matter due to condensation enters the pipes.y The rust cannot be removed by cleaning, and newpipes are necessary.Placementlocation Term Curing mannerOutdoors 1 month or more PinchingLess than 1 month Pinching or tapingIndoors Every timeAre there scratches or dents on the existing pipes?Is it possible to operate the existing air conditioner?y After the existing air conditioner is operated in coolingmode for approx. 30 minutes or longer,* recover therefrigerant.y For cleaning the pipes and recovering oily Refrigerant recovery: Pump down methody Remove the existing air conditioner from the pipingand carry out flushing (nitrogen pressure 0.5 MPa) toremove any remains inside of the pipe.Note: In case of twin pipes, also be sure to flush thebranching pipe.Connect the indoor / outdoor units to the existing pipe.y Use a flare nut attached to the main unit for the indoor/ outdoor units. (Do not use the flare nut of the existingpipe.)y Re-machine the flare machining size to size for R410A.y (Airtight test), Vacuum dry, Refrigerant charge, Gasleak checkTest runWas largely discolored oil or a large quantityof remains discharged? (When the oil deteriorates,the color of the oil changes to a muddyor black color.)Existing pipes: Cannot be used.y Use new pipes.Clean the pipes or use new pipes.Piping necessary to change the flare nut / machiningsize due to pipe compression1) Flare nut width: HH(mm)Copper pipeouter diameter Ø6.4 Ø9.5 Ø12.7For R410A 17 22 26For R22 Same as above 242) Flare machining size: AA(mm)Copper pipeouter diameter Ø6.4 Ø9.5 Ø12.7For R410A 9.1 13.2 16.6For R22 9.0 13.0 16.2Becomes a little larger for R410ADo not apply refrigerator oil to the flare surface.(If there is discharge of remains, it is judged that alarge quantity of remains are present.)YESYESNONONOYESNitrogen gas pressure 0.5 MPa