If the propylene glycol concentration level is too high, what should be added?

In the context of managing propylene glycol concentration levels, adding deionized water is the appropriate choice. Deionized water is free of impurities and dissolved minerals, making it an ideal diluent for chemical solutions. When the concentration of propylene glycol is too high, diluting it with deionized water effectively reduces the concentration without introducing any contaminants that could alter the properties or efficiency of the system.

Deionized water ensures that the system remains clean and operationally efficient. It helps in preventing scale formation or unwanted reactions that might occur if minerals or other impurities were present, which could happen if distilled water or tap water were used.

While distilled water is also a pure form of water, it is typically more expensive and may not be as accessible as deionized water for regular use in industrial contexts. Tap water contains various minerals and chemicals that could negatively impact the system's performance. Antifreeze solution might contain additives that are not necessary for dilution and could complicate the chemical balance within the system.