If you want lower chilled water temperatures, you’ll need to mix process water with industrial- (not automotive) grade ethylene or propylene glycol with rust inhibitor to provide protection down to 20°F (12ºC) below the operating temperature you want. Figure 3 below shows the proper mixtures needed to provide protection to 20°F (12ºC) below the operating temperature you want. You can then reset the freezestat cutout temperature to a temperature of 10°F (6ºC) below the operating temperature you selected.
Caution!
Make sure all freezestat adjustments are performed
by a qualified refrigeration service technician.
The Sterling product warranty does not cover system
Figure 3
Freezing Protection Curve
Ethylene glycol required for evaporator freeze protection
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Ethylene | 40 |
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glycol | 30 |
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percent by |
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volume | 20 |
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| 0ºF | 10ºF | 20ºF | 30ºF | 40ºF | 50ºF | 60ºF | |||||
| 4ºC | 10ºC | 16ºC |
Chilled water operating temperature ºF / ºC
Page 30 of 77 | SCW Series Central Chilling Stations |
