Daikin VRV RXYQ72XBYC Series Installation Manual

Also see for VRV RXYQ120XBYC Series: Operation manual

29EnglishNOTE• If the power of some units is turned off, the charging procedure can-not be finished properly.• In case of a multiple outdoor system, turn on the power of all out-door units.• Make sure to turn ON the power 6 hours before starting the opera-tion. This is necessary to warm the crankcase by the electric heater.• If operation is performed within 12 minutes after the indoor andoutdoor units are turned on, the compressor will not operate beforethe communication is established in a correct way between outdoorunit(s) and indoor units.• Before starting charging procedures, check if the segment displayindication of the main printed circuit board (A1P) is as normal (seefunctions of the push button switches which are located on the mainprinted circuit board (A1P) on page 24). If a malfunction code ispresent, see 15.5. Malfunction code list on page 40.• Make sure all connected indoor units are recognized (see15.2. Monitoring function and field settings on page 31).• Close the front panel before any refrigerant charge operation isexecuted. Without the front panel attached the unit cannot judgecorrectly whether it is operating properly or not.14.3.2. Charging methodAs explained during vacuum drying method, once vacuum drying isfinished, additional refrigerant charging can start.A flow chart is available which gives an overview of the possibilitiesand actions to be taken (see 14.3.1. Flow chart on page 28).To speed up the process of pre-charging refrigerant for large systems,it is recommended to first charge a portion of the refrigerant beforeperforming refrigerant charging operation of outdoor unit. This step isincluded in below procedure. This step can be skipped, but chargingwill take longer in such a case.Follow the steps as described below.1 Calculate the additional amount of refrigerant to be added usingthe formula mentioned in 14.2. Calculating the additional refriger-ant charge on page 26.2 The first 22 lbs. (10 kg) of additional refrigerant can be chargedwithout outdoor unit operation.If the additional refrigerant amount is smaller than 22 lbs. (10 kg),perform the pre-charging procedure as explained in step 3 and 4abelow.If the additional refrigerant charge is larger than 22 lbs. (10 kg),perform step 3 till the end of the procedure.3 Pre-charging can be done without compressor running by con-necting the refrigerant tank only to the liquid stop valve service port(open valve A). Make sure that all outdoor unit stop valves, as wellas valve B are closed.12 3456AB879 9910121113141 Pressure reducing valve2 Nitrogen3 Measuring instrument4 Refrigerant R410A tank (siphon system)5 Vacuum pump6 Charge hose7 Gas pipe stop valve8 Liquid pipe stop valve9 Outdoor unit10 To indoor unit11 Stop valve12 Field piping13 Gas flow14 Stop valve service portA Valve AB Valve B4 a) If the calculated additional refrigerant amount is reached byabove pre-charging procedure, close valve A.b) If the total amount of refrigerant could not be charged by pre-charging, then close valve A and go to step 5.INFORMATIONIf the total additional refrigerant amount was reached in step 4 (bypre-charging only), record the amount of refrigerant that was addedon the additional refrigerant charge label provided with the unit andattach it on the back side of the front panel. Perform the test procedureas described in 15.4. Test operation on page 39.5 After pre-charging, perform the refrigerant charge operation asshown below and charge the remaining refrigerant of the additionalcharging amount through valve B.Open all outdoor units stop valves. Valves A and B must remainclosed!NOTEIn order to ensure uniform refrigerant distribution, it may take the com-pressor ±10 minutes to start up after the unit has started operation.This is not a malfunction.6 The remaining additional refrigerant charge can be charged byoperating the outdoor unit by means of the refrigerant chargeoperation mode:• Turn on the power of the indoor units and outdoor unit.• Take all the precautions mentioned in start-up and configura-tion into account.• Activate outdoor unit setting [2-20]=1 to start refrigerant chargemode. Refer to page 32 for details.Result: The unit will start operation. Valve A can be opened.Charging of remaining additional refrigerant can be done.When the remaining calculated additional refrigerant amount isadded, close valve A and push BS3 to stop the refrigerant charg-ing procedure.