What Factors Increase the Frequency of Corrosion Related Leaks in Wet Pipe Fire Sprinkler Systems?

Oxygen exposure and higher temperatures increase the rate of corrosion

Each time air is introduced into the fire sprinkler system piping the oxygen corrosion reaction is turned back on. It continues until the newly introduced oxygen is consumed by the corroding pipe. Every time a wet pipe system is drained and refilled the corrosion rate accelerates.
The higher the temperature of the fire sprinkler system, the faster the corrosion rate. As a rule, every 18-degree increase in temperature doubles the corrosion rate. That means sprinkler systems exposed to direct sunlight and in locations above equipment that produces heat will have higher corrosion rates than the rest of the system piping.