Standard Chiller/HP modulare per compressore a vite con driver CAREL
Cod.: +030221241 Rel. 1.0 dated 25 September 03
44
20.5 Antifreeze control
Inputs used:
• Water temperature at evaporator outlet
• Water temperature at condenser outlet
Parameters Used
:
• Enable evaporator outlet probe
• Enable condenser outlet probe
• Antifreeze heater set point
• Antifreeze heater differential
• Antifreeze alarm set point
• Antifreeze alarm set point
• Forcing of main pump due to antifreeze alarm
Outputs used :
• Antifreeze heater
• General alarm relays
• All compressor outputs
• Main circulation pump
20.5.1 Description of operation
Every pCO unit is able to manage antifreeze control providing the water temperature probe at evaporator/condenser outlet is connected and
enabled according to the type of unit being controlled.
Antifreez
e alarm
set point
Antifreeze alarm
differential
Antifreeze
heater set
point
Antifreeze heater
differential
Activation of antifreeze
alarm
Activation of antifreeze
heater
Antifreeze control is always enabled, even if the machine is OFF, both in summer and winter operating modes.
For type 5 machines with reversing of the water circuit, the antifreeze control always controls water temperature at evaporator outlet, shifting
control to the evaporator or condenser according to the operating mode (summer-winter).
The antifreeze alarms is a system alarm in multi-card systems. If present on any unit, it will totally shut down the machine.
A control parameter is provided, which enables you to select whether to keep the main circulation pump ON or OFF in the event of an
antifreeze alarm