What maximum percentage of glycerin should be used to protect from freezing?

Using a maximum of 50% glycerin in a sprinkler system helps prevent the freezing of the fluid within the system. Glycerin is commonly used in antifreeze solutions because it has a lower freezing point when mixed with water compared to water alone. At a concentration of 50%, glycerin effectively lowers the freezing point, making it suitable for environments where temperatures can drop below freezing.

In addition, exceeding the 50% concentration can lead to issues such as poor performance of the sprinkler system. High concentrations of glycerin can become too viscous, which could impede the flow of the fluid, reducing the effectiveness of the sprinkler in an emergency situation. Therefore, maintaining the glycerin concentration at or below this level ensures both the antifreeze protection and operational efficiency of the sprinkler system.