User's Manual of Fiber Laser Chiller
21
8.2 Winter frost protection
Fig. 12 Winter frost protection maintenance
When the appliance is in transport or not in use for a long period of time, the water in the
tank should be drained through the drain valve and the remaining water in the pump should be
drained by loosening the drain screw plug under the pump, as shown in Figure 12.
If the ambient temperature is below 2°C at night, the customer is advised not to stop or to
add antifreeze. The glycol volume ratio is selected according to Table 1 and the freezing point
prevented is equal to the ambient temperature at which the equipment is located minus
approximately 5°C. When the average daily temperature is above 5°C, replace the water
containing the antifreeze with softened water.
Table 1 Correspondence between different volume ratios of ethylene glycol and freezing
point
14.6
-6.3
39.8
-26.0
87.3
-33.0
16.5
-7.3
41.8
-28.0
89.4
-29.0
18.4
-8.0
43.8
-31.0
91.5
-26.0
20.3
-9.0
45.8
-33.0
93.6
-23.0
Volume
ratio/%
Freezing
point/°C
Volume
ratio/%
Freezing
point/°C
Volume
ratio/%
Freezing
point/°C
1.8
-0.6
26.0
-13.0
51.9
-41.0
3.6
-1.3
28.0
-15.0
53.9
-44.0
5.4
-2.0
29.9
-17.0
56.0
-48.0
7.2
-2.7
31.9
-18.0
78.9
-47.0
9.1
-3.5
33.8
-20.0
81.0
-43.0
10.9
-4.4
35.8
-22.0
83.1
-40.0
12.8
-5.3
37.8
-24.0
85.2
-36.0