Sterlco GC Series Central Chiller - Manual (Page 27)

GC Series Central Chillers Chapter 3: Installation 27 of 79
Figure 9: Ethylene Glycol and Propylene Glycol Curves
Percent Glycol Curves for Freeze Protection
-60.0
-50.0
-40.0
-30.0
-20.0
-10.0
0.0
10.0
20.0
30.0
40.0
0.0 10.0 20.0 30.0 40.0 50.0 60.0
% Glycol by Volume
Ethylene Glycol
Propylene Glycol
Example: 45°F set point minus 20°F = 25°F.
From Figure 28, 25°F equates to 10% by volume of glycol required.