Daikin FXFQ12MVJU Installation Manual

Also see for FXFQ12MVJU: Serivce manual Serveice manual Service manual Design, Installation & Testing Instruction Engineering data

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Daikin FXFQ12MVJU Installation Manual Manual pdf 9 page image

8NOTE• Apply ester oil or ether oil around the flare portions beforeconnecting.• The flare nuts used must be those included with the mainbody.• Over-tightening may damage the flare and cause a refriger-ant leakage.Not recommendable but in case of emergencyYou must use a torque wrench but if you are obliged toinstall the unit without a torque wrench, you mayfollow the installation method mentioned below.After the work is finished, make sure to check thatthere is no gas leak.When you keep on tightening the flare nut with a spanner,there is a point where the tightening torquesuddenly increases. From that position, further tighten theflare nut the angle shown below:Table 47-3 Piping insulation• Execute heat insulation work completely on both sides of thegas piping and the liquid piping. Otherwise, a water leakagecan result sometimes.• When using a heat pump, the temperature of the gas pipingcan reach up to approximately 250°F, so use insulationwhich is sufficiently resistant.• Also, in cases where the temperature and humidity of the refrig-erant piping sections might exceed 86°F or RH80%, reinforcethe refrigerant insulation. (13/16” or thicker) Condensation mayform on the surface of the insulating material.• Check the pipe connector for gas leaks, then insulate it asshown in the drawing below.• Make absolutely sure to execute heat insulation works on thepipe-connecting section after checking gas leakage by thor-oughly studying the following figure and using the attachedheat insulating materials for fitting. (Fasten both ends withthe clamps (accessory).)• Wrap the sealing pad (accessory) only around the insulationfor the joints on the gas piping side.CAUTIONBe sure to insulate any field piping all the way to the pipingconnection inside the unit. Any exposed piping may causecondensation or burns if touched.7-4 Brazing referigerant piping• Before brazing local refrigerant piping, nitrogen gas shall beblown through the piping to expel air from the piping.If your brazing is done without nitrogen gas blowing, a largeamount of oxide film develops inside the piping, and couldcause system malfunction.• When brazing the refrigerant piping, only begin brazing afterhaving carried out nitrogen substitution or while insertingnitrogen into the refrigerant piping. Once this is done, con-nect the indoor unit with a flared or a flanged connection.• Nitrogen should be set to 2.9psi. with a pressure-reducingvalve if brazing while inserting nitrogen into the piping.NOTEDo not use flux when brazing refrigerant piping. Therefore,use the phosphor copper brazing filter metal (BCuP) whichdoes not require flux.(Flux has extremely harmful infulence on refrigerant pipingsysems. For instance, if the chlorine based flux is used, itwill cause pipe corrosion or, in particular, if the flux containsfluorine, it will damage the refrigerant oil.)8. DRAIN PIPING WORK〈〈Rig the drain pipe as shown below and take measuresagainst condensation. Improperly rigged piping could leadto leaks and eventually wet furniture and belongings.〉〉(1) Rig drain piping• The diameter of the drain pipe should be greater than orequal to the diameter of the connecting pipe (vinyl tube; pipesize: 1”; outer dimension: 1 1/4”). (This does not apply torises.)• Keep the drain pipe short and sloping downwards at a gradi-ent of at least 1/100 to prevent air pockets from forming.• If the drain hose cannot be sufficiently set on a slope, exe-cute the drain raising piping.• To keep the drain hose from sagging, space hanging wiresevery 3.28 ~ 4.92ft .Pipe size Further tighteningangleRecommended arm length oftool (in.)φ 1/4” 60 to 90 degrees Approx. 5 7/8φ 3/8” 60 to 90 degrees Approx. 7 7/8φ 1/2” 30 to 60 degrees Approx. 9 13/16φ 5/8” 30 to 60 degrees Approx. 11 13/16