Panasonic PAW-500ZDX3N Installation, Use And Maintenance Manual

Also see for ERV+DX Series: Installation, use and maintenance manual

Contents

English3.8 Connecting the Refrigerant TubingCAUTIONS DURING BRAzINGReplace air inside the tube with nitrogen gas to prevent copper oxide film from forming during the brazing process. (Oxygen, carbon dioxideand Freon are not acceptable.)● Do not allow the tubing to get too hot during brazing.The nitrogen gas inside the tubing may overheat, causing refrigerant system valves tobecome damaged. Therefore allow the tubing to cool when brazing.● Use a reducing valve for the nitrogen cylinder.● Do not use agents intended to prevent the formation of oxide film. These agents adversely affect the refrigerant and refrigerant oil, and maycause damage or malfunctions.TIGhTENINGIn the table below are shown the pipes diameter for each unitFor the flare nuts at tubing connections, be sure to use the flare nuts that were supplied with the unit, or else flare nuts for R410A. The refrige-rant tubing that is used must be of the correct wall thickness as shown in the table below.Because the pressure is approximately 1.6 times higher than conventional refrigerant pressure, the use of ordinary flare nuts or thin-walledtubes may result in tube rupture, injury, or asphyxiation caused by refrigerant leakage.● In order to prevent damage to the flare caused by overtightening of the flare nuts, use the table above as a guide when tightening.● When tightening the flare nut on the liquid tube, use an adjustable wrench with a nominal handle length of 200 mm.INSUlATING ThE REfRIGERANT TUBINGThermal insulation must be applied to all units tubing, including distribution joint (field supply). For gas tubing, the insulation material must beheat resistant to 120°C or above. For other tubing, it must be heat resistant to 80°C or above.Insulation material thickness must be 10 mm or greater.If the conditions inside the ceiling exceed DB 30°C and RH 70%, increase the thickness of the gas tubing insulation material by 1 step.Unit PAW 500 PAW 800 PAW 1000Gas Pipe ø 12,7 mmLiquid Pipe ø 6,35 mmø Tube Tightening torque Tube thicknessø 6,35 (1/4”) 14 - 18 N*m 0,8 mmø 12,7 (1/2)” 49 - 55 N*m 0,8 mmInstallation, Use and Maintenance Manual - ERV+DX series pag. 29