Maintain Glycol Level - Trane Manhattan Gen II Installation, Operation And Maintenance Manual

Operating Procedures
Protect the chiller from freezing, particularly if the chiller
has a set point that is lower than the freezing point of the
water/glycol mixture in the chiller. The chiller is designed
to operate with a maximum propylene glycol
concentration of 50%. See below table, for the effects on
the chiller when operating with other glycol
concentrations.
This table shows the capacity reduction and the pressure
drop that occurs when higher concentrations of glycol are
used.

Maintain Glycol Level

When the chiller has a water set point that is below the
freezing point of the water/glycol in use, take precautions
against freezing.
The glycol concentration should be based on the lowest
fluid design temperature. See Table 8, p. 41, provides
guidelines for adding propylene glycol.
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