Blue Box
4.15 OPERATION WITH LOW TEMPERATURE CHILLED WATER AT EVAPORATOR ............... 48
TABLE 2 - FREEZING POINT FOR WATER-ANTIFREEZE MIXTURES ........................... 48
OPERATING LIMITS - R22 refrigerant .................................................................... 49
OPERATING LIMITS - R407C refrigerant ................................................................ 51
EVAPORATOR PRESSURE DROP ........................................................................... 53
PUMPS AVAILABLE PRESSURE - MODEL ZETA 2002 /ST 2PS ................................ 54
4.16 ELECTRICAL CONNECTIONS .................................................................................... 55
4.16.1 General ........................................................................................................... 55
4.16.2 Power supply to crankcase heaters ....................................................................... 56
4.16.3 Potential free contacts ......................................................................................... 56
4.16.4 Flow switch electrical connections ........................................................................ 56
4.16.5 Circulating pump electrical connections ................................................................ 56
4.17 MICROPROCESSOR CONTROLLERS ........................................................................... 56
4.17.1 Microprocessor controller for /LE and HP/LE versions .............................................. 57
4.17.2 RS485 serial interface (optional) ........................................................................... 57
ELECTRICAL PANEL LAY OUT .................................................................................. 58
5. START-UP ........................................................................................................... 60
5.1 PRELIMINARY CHECKS............................................................................................ 60
6UNITS WITH µCHILLER MICROPROCESSOR (models from 3.2 to 13.2)......................... 61
6.1 INTRODUCTION ...................................................................................................... 61
6.1.1 Display ........................................................................................................... 61
6.1.2 Machinestatusinformation.................................................................................. 61
6.1.3 Keypad ........................................................................................................... 61
6.1.4 Controls and display screens ................................................................................ 62
6.1.5 Muting the BUZZER............................................................................................. 62
6.1.6 ALARMS reset .................................................................................................... 62
6.1.7 Activation/deactivationofCOOLINGoperation (Summer mode) ............................. 63
6.1.8 Activation/deactivation of HEATING mode (winter mode) ...................................... 63
6.1.9 Switching off the machine (stand by).................................................................... 63
6.1.10 Inlet water temperature control ............................................................................ 64
6.1.11 Defrosting (heat pump mode only) ....................................................................... 64
6.2 STARTING THE UNIT ............................................................................................... 66
6.3 STOPPING THE UNIT ............................................................................................... 66
6.3.1 Temporary stop ................................................................................................... 66
6.3.2 Seasonal stop ..................................................................................................... 67
6.4 EMERGENCY STOP ................................................................................................. 67
7. TROUBLESHOOTING ................................................................................................ 67
8UNIT WITH pCO2MICROPROCESSOR (models from 14.4 to 26.4) ............................... 75
8.1 INTRODUCTION ...................................................................................................... 75
8.1.1 Display ........................................................................................................... 75
8.1.2 Keypad ........................................................................................................... 75
8.2 OPERATING DESCRIPTION ....................................................................................... 77
8.2.1 Introduction ........................................................................................................ 77
8.2.2 Unit in stand-by mode ......................................................................................... 77
8.2.3 Enabling the unit................................................................................................. 77
8.2.4 Pumps management (ST units only)...................................................................... 77
8.2.5 Compressorstart up ............................................................................................ 77
8.2.7 Heat pump mode operation ................................................................................. 78
8.2.8 Evaporatorlowtemperaturechilledwaterprotection ............................................. 78
8.2.9 No-frostheaterinstalledontheevaporator(optional)............................................. 78
8.2.10 Compressor operation ......................................................................................... 78
8.2.11 Compressors management .................................................................................. 79
8.2.12 High and low pressure alarms .............................................................................. 79
