Carrier 53QG18-H Installation Manual

29Corrugated CuttingWrap CuttingCONNECTING REFRIGERANT PIPING LINES (Cont.)15-9 STEPS FOR PREPARING REFRIGERANT PIPING LINES BEFORE CONNECTIONS( IN CASE OF NOT USING THE OPTIONAL FACTORY REFRIGERANT PIPING LINES WITH THE FLARE NUTS )STEP (1): Cutting refrigerant piping lines• Remove protective caps from copper pipe ends.• Position tube end downwards, cut the pipe to therequired length with a pipe cutter.NOTE:• It is recommended to cut approx. 30→50 cmlonger than the estimated pipe length.• Take care to ensure that the cut edge remains at a90° angle with the side of pipe, and refer to theillustrations for examples of edges cut correctlyand incorrectly.Removing the burrs• Remove burrs at the end of the connection pipewith a pipe reamer or a file.This process is important and should be donecarefully to make a good flare and to prevent anygas leaking out.NOTE:When reaming, hold the pipe end downward andbe sure that no copper scraps fall into the pipe.STEP (2): Removing the flare nuts from theindoor unit.Remove the suction and liquid flare nuts from theindoor unit connections.NOTES:• Do not remove the flare nuts from the indoor unituntil refrigerant piping lines are ready forconnections.• It is that easier to remove flare nuts from theindoor unit before being installed on the wall hangbracket.STEP (3): Removing the flare nuts from theoutdoor unit Remove the suctionand liquid flare nuts from theoutdoor unit connections.NOTES:• Do not remove the flare nuts from the outdoor unituntil refrigerant piping lines are ready forconnection.• It is easier to remove flare nuts from the outdoorunit before being installed on the wall support.DebarringAfterBefore1: Connection pipes2: Reamer12Pipe CutterCorrect CuttingInclined Cutting