Hitachi UTOPIA R32 Series - 9 Piping Work and Refrigerant Charge

9 Piping work and refrigerant charge
TCGB0136 rev.1 - 05/2021
83
9
9. Piping work and refrigerant charge
Index
9.1 Refrigerant pipe selection......................................................................................................................84
9.1.1 Pipe size selection ......................................................................................................................................... 84
9.1.2 Multikit or distributor selection ....................................................................................................................... 84
9.2 Refrigerant piping range ........................................................................................................................84
9.2.1 Refrigerant piping length ............................................................................................................................... 84
9.2.2 Piping system for header branch ................................................................................................................... 85
9.2.3 Maximum lenght of refrigerant piping ............................................................................................................ 86
9.2.4 Combinations of piping size and piping length .............................................................................................. 88
9.2.5 Refrigerant piping size and multikit/distributor ............................................................................................... 88
9.3 Copper pipes, sizes and connection .....................................................................................................90
9.3.1 Copper pipes and sizes ................................................................................................................................. 90
9.3.2 Insulation ....................................................................................................................................................... 91
9.4 Refrigerant charge amount....................................................................................................................92
9.4.1 Refrigerant charge before shipment (W
0
(kg)) ............................................................................................... 92
9.4.2 Calculation method for the additional refrigerant charge ............................................................................... 92
9.5 Caution in case of refrigerant leakage...................................................................................................94
9.5.1 Maximum permitted concentration of hydrouorocarbon (HFC) ................................................................... 94
9.5.2 Calculation of refrigerant concentration ......................................................................................................... 94
9.5.3 Countermeasure for R410A refrigerant leakage ............................................................................................ 95