Trane SINTESIS ADVANTAGE CGAF Series Installation Operation & Maintenance page 46

Evaporator Waterside (not for free-cooling version)
Low Refrigeration Temperature Setpoint
and Antifreeze Setpoint on CGAF and
CXAF Unit Control
CAUTION! The chiller is provided with standard
factory settings. It can be necessary to modify the
low refrigerant cutout temperature and the antifreeze
setpoint on the unit control. Based on the following
examples, it is necessary to modify on the unit control
the following settings:
• The LP saturation temperature
• The antifreeze setpoint
Examples for:
• 7°C, the LRTC setting must be -4°C where the
antifreeze setting shall be 2°C
• 0°C, the LRTC setting must be -12°C where the
antifreeze setting shall be -6°C
Figure 7 – Low refrigerant cutout temperature setpoint and antifreeze water temperature based on active chilled
water setpoint
46
Freeze Protection with Glycol
It is mandatory to use a freeze inhibitor for leaving
water setpoint less or equal to 5°C. On the glycol
recommended concentration figure, you must select
concentration on or above the curve. For example, for
-4°C brine temperature, a concentration of 25% ethylene
glycol is not sufficient. The concentration must be 28%
ethylene glycol or 33% propylene glycol.
Using Glycol with Hydraulic Module
If the glycol brine percentage is not at the recommended
percentage (greyed area), corrosion inhibitor present
in the glycol may not be efficient enough. For instance,
a glycol concentration of 15% will provide freeze
protection to the unit down to -5°C, but it might generate
additional corrosion.
CG-SVX039C-GB