Daikin RWEYQ8T9Y1B Installation And Operation Manual

Also see for RWEYQ10T9Y1B: Installer and user guide Installer and user reference guide Installation and operation manual

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5 InstallationInstallation and operation manual17RWEYQ8~14T9V1B+RWEYQ8~14T9Y1BVRV IV water-cooled system air conditioner4P452190-1A – 2017.04NOTICEThe connections to the indoor units and all indoor unitsshould also be leak and vacuum tested. Keep any possible(field supplied) field piping valves open as well.Refer to the indoor unit installation manual for more details.Leak test and vacuum drying should be done before thepower supply is set to the unit. If not, see also the flowchart earlier described in this chapter (see "5.4.1 Aboutchecking the refrigerant piping" on page 16).5.4.4 To perform a leak testThe leak test must satisfy the specifications of EN378‑2.To check for leaks: Vacuum leak test1 Evacuate the system from the liquid and gas piping to–100.7 kPa (–1.007 bar) (5 Torr absolute) for more than 2hours.2 Once reached, turn off the vacuum pump and check that thepressure does not rise for at least 1 minute.3 Should the pressure rise, the system may either containmoisture (see vacuum drying below) or have leaks.To check for leaks: Pressure leak test1 Break the vacuum by pressurising with nitrogen gas to aminimum gauge pressure of 0.2 MPa (2 bar). Never set thegauge pressure higher than the maximum operation pressure ofthe unit, i.e. 4.0 MPa (40 bar).2 Test for leaks by applying a bubble test solution to all pipingconnections.3 Discharge all nitrogen gas.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).5.4.5 To perform vacuum dryingTo remove all moisture from the system, proceed as follows:1 Evacuate the system for at least 2 hours to a target vacuum of–100.7 kPa (–1.007 bar) (5 Torr absolute).2 Check that, with the vacuum pump turned off, the targetvacuum is maintained for at least 1 hour.3 Should you fail to reach the target vacuum within 2 hours ormaintain the vacuum for 1 hour, the system may contain toomuch moisture. In that case, break the vacuum by pressurisingwith nitrogen gas to a gauge pressure of 0.05 MPa (0.5 bar)and repeat steps 1 to 3 until all moisture has been removed.4 Depending on whether you want to immediately chargerefrigerant through the refrigerant charge port or first pre-chargea portion of refrigerant through the liquid line, either open theoutdoor unit stop valves, or keep them closed. See "5.6.2 Aboutcharging refrigerant" on page 18 for more information.5.5 To insulate the refrigerant pipingAfter finishing the leak test and vacuum drying, the piping must beinsulated. Take into account the following points:▪ Make sure to insulate the connection piping and refrigerant branchkits entirely.▪ Be sure to insulate the liquid and gas piping (for all units).▪ Use heat resistant polyethylene foam which can withstand atemperature of 70°C for liquid piping and polyethylene foam whichcan withstand a temperature of 120°C for gas piping.▪ Reinforce the insulation on the refrigerant piping according to theinstallation environment.AmbienttemperatureHumidity Minimum thickness≤30°C 75% to 80% RH 15 mm>30°C ≥80% RH 20 mmCondensation might form on the surface of the insulation.▪ If there is a possibility that condensation on the stop valve mightdrip down into the indoor unit through gaps in the insulation andpiping because the outdoor unit is located higher than the indoorunit, this must be prevented by sealing up the connections. Seebelow figure.3×aba Insulation materialb Caulking etc.5.6 Charging refrigerant5.6.1 Precautions when charging refrigerantWARNING▪ Only use R410A as refrigerant. Other substances maycause explosions and accidents.▪ R410A contains fluorinated greenhouse gases. Itsglobal warming potential (GWP) value is 2087.5. DoNOT vent these gases into the atmosphere.▪ When charging refrigerant, always use protectivegloves and safety glasses.NOTICEIf the power of some units is turned off, the chargingprocedure cannot be finished properly.NOTICEIn case of a multiple outdoor system, turn on the power ofall outdoor units.NOTICEBe sure to turn on the power 6 hours before operation inorder to have power running to the crankcase heater andto protect the compressor.NOTICEIf operation is performed within 12 minutes after the indoorand outdoor units are turned on, the compressor will notoperate before the communication is established in acorrect way between outdoor unit(s) and indoor units.