4 InstallationInstallation manual9(A)RXP20~35L5V1B + RXF20~35A5V1B + RXF20~25B5V1BR32 split series3P519299-2H – 2019.09▪ Piping protection. Protect the field piping against physicaldamage.1 Connect the liquid refrigerant connection from the indoor unit tothe liquid stop valve of the outdoor unit.abca Liquid stop valveb Gas stop valvec Service port2 Connect the gas refrigerant connection from the indoor unit tothe gas stop valve of the outdoor unit.NOTICEIt is recommended that the refrigerant piping betweenindoor and outdoor unit is installed in a ducting or therefrigerant piping is wrapped with finishing tape.4.4 Checking the refrigerant piping4.4.1 To check for leaksNOTICEDo NOT exceed the unit's maximum working pressure (see"PS High" on the unit name plate).NOTICEMake sure to use a recommended bubble test solutionfrom your wholesaler. Do not use soap water, which maycause cracking of flare nuts (soap water may contain salt,which absorbs moisture that will freeze when the pipinggets cold), and/or lead to corrosion of flared joints (soapwater may contain ammonia which causes a corrosiveeffect between the brass flare nut and the copper flare).1 Charge the system with nitrogen gas up to a gauge pressure ofat least 200 kPa (2 bar). It is recommended to pressurize to3000 kPa (30 bar) in order to detect small leaks.2 Check for leaks by applying the bubble test solution to allconnections.3 Discharge all nitrogen gas.4.4.2 To perform vacuum drying1 Vacuum the system until the pressure on the manifold indicates−0.1 MPa (−1 bar).2 Leave as is for 4-5 minutes and check the pressure:If the pressure… Then…Does not change There is no moisture in thesystem. This procedure isfinished.Increases There is moisture in thesystem. Go to the next step.3 Vacuum the system for at least 2 hours to a manifold pressureof −0.1 MPa (−1 bar).4 After turning the pump OFF, check the pressure for at least1 hour.5 If you do NOT reach the target vacuum or CANNOT maintainthe vacuum for 1 hour, do the following:▪ Check for leaks again.▪ Perform vacuum drying again.NOTICEMake sure to open the stop valves after installing therefrigerant piping and performing vacuum drying. Runningthe system with the stop valves closed may break thecompressor.4.5 Charging refrigerant4.5.1 About charging refrigerantThe outdoor unit is factory charged with refrigerant, but in somecases the following might be necessary:What WhenCharging additional refrigerant When the total liquid pipinglength is more than specified(see later).Completely recharging refrigerant Example:▪ When relocating the system.▪ After a leak.Charging additional refrigerantBefore charging additional refrigerant, make sure the outdoor unit'sexternal refrigerant piping is checked (leak test, vacuum drying).INFORMATIONDepending on the units and/or the installation conditions, itmight be necessary to connect electrical wiring before youcan charge refrigerant.Typical workflow – Charging additional refrigerant typically consistsof the following stages:1 Determining if and how much you have to charge additionally.2 If necessary, charging additional refrigerant.3 Filling in the fluorinated greenhouse gases label, and fixing it tothe inside of the outdoor unit.Completely recharging refrigerantBefore completely recharging refrigerant, make sure the following isdone:1 All refrigerant is recovered from the system.2 The outdoor unit's external refrigerant piping is checked (leaktest, vacuum drying).3 Vacuum drying on the outdoor unit's internal refrigerant piping isperformed.NOTICEBefore completely recharging, perform vacuum drying onthe outdoor unit's internal refrigerant piping as well.Typical workflow – Completely recharging refrigerant typicallyconsists of the following stages:1 Determining how much refrigerant to charge.2 Charging refrigerant.3 Filling in the fluorinated greenhouse gases label, and fixing it tothe inside of the outdoor unit.4.5.2 About the refrigerantThis product contains fluorinated greenhouse gases. Do NOT ventgases into the atmosphere.Refrigerant type: R32Global warming potential (GWP) value: 675