Carrier 30KAV-ZE Series - Page 77

Required glycol concentration
Freezing curve for Ethylene and Propylene glycol
Glycol concentration (%)
0
5
10
15
20
25
30
35
40
45
50
-26 -24 -22 -20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0
Ethylène glycol (%)
Propylène glycol (%)
Minimum frost protection temperature (°C)
Ethylene glycol (%)
Propylene glycol (%)
For example, based on the curves given above, if the mass
concentration measurement for ethylene glycol measured in the
loop is 30 %, the frost protection temperature value to be entered
in the software is -14.8 °C.
Here under you can find tables to help you to define the
concentration of glycol you need to mix with your water loop.
Following the water temperature at chiller inlet (EWT) and at chiller
outlet (LWT), you can determine the evaporator DT as equal to
[EWT-LWT].
Then the tables provide the minimum glycol concentration so that
the evaporator does not freeze.
Minimum glycol concentration
30KAVZE option 6
Fluid type: EG
Evaporator Delta T °C
[EWT (°C) - LWT (°C)]
3 4 6 8
Evaporator water outlet
LWT (°C)
3 1 % 2 % 3 % 5 %
2 4 % 4 % 6 % 8 %
1 6 % 7 % 9 % 11 %
0 9 % 10 % 11 % 14 %
-1 11 % 12 % 14 % 17 %
-2 14 % 15 % 17 % 19 %
-3 16 % 17 % 19 % 22 %
-4 19 % 20 % 22 % 25 %
-5 21 % 22 % 25 % 27 %
-6 24 % 25 % 27 % 30 %
-7 26 % 27 % 29 % 33 %
-8 28 % 29 % 30 % 35 %
-9 31 % 32 % 35 % 35 %
-10 34 % 35 % 35 % 35 %
-11 35 % 35 % 35 % -
-12 35 % 35 % - -
Minimum glycol concentration
30KAVZE option 6
Fluid type: PG
Evaporator Delta T °C
[EWT (°C) - LWT (°C)]
3 4 6 8
Evaporator water outlet
LWT (°C)
3 4% 7% 12% 17%
2 7% 9% 15% 19%
1 9% 12% 17% 22%
0 12% 15% 20% 24%
-1 15% 18% 22% 26%
-2 18% 20% 25% 29%
-3 21% 23% 28% 31%
-4 23% 26% 30% 34%
-5 26% 28% 33% 35%
-6 29% 31% 35% 35%
-7 31% 34% 35% 35%
-8 34% 35% 35% -
-9 35% 35% - -
-10 35% - - -
IMPORTANT:
■ It is vital to perform a (minimum) annual inspection of the
glycol content and adjust the software's frost protection
based on the measured level.
■ This procedure must be performed systematically if water
or antifreeze solution is added.
■ Observe the minimum frost protection temperature based
on the leaving water temperature.
12 - OPTIONS
77