AEC 2-40 HP Portable Chillers - Manual (Page 27)

2-40 HP Portable Chillers Chapter 3: Installation 26 of 78
Figure 6: Ethylene Glycol and Propylene Glycol Curves
Pe rce n t G lyc ol Cu rves for Free ze P rotec 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 lycol
P rop ylene Glycol
Example: 45°F set point minus 20°F = 25°F.
From Figure 28, 25°F equates to 10% by volume of glycol required.