Sterling GP Series - Manual (Page 18)

GP Series Portable Chillers Chapter 3: Installation 18 of 44
Figure 2: Ethylene Glycol and Propylene Glycol Curves
Pe rce n t G lyc o l Cu rves fo r F ree ze P ro tec tion
-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
% Gl ycol by Vol um e
Eth ylene G ly col
P rop ylene G lyc ol
Example: 45°F set point minus 20°F = 25°F.
From Figure 28, 25°F equates to 10% by volume of glycol required.