Dry sprinkler systems are designed for cold environments, but that does not make them immune to winter damage.
As temperatures rise and fall, dry systems naturally pull humid air into the piping. That moisture condenses and settles at low points within the system. When temperatures drop, even a small amount of trapped water can freeze, expand, and rupture steel pipe or fittings.
The reality is simple. It only takes a small amount of water and one hard freeze to cause serious damage. That is why winter preparation is not optional. It is essential.
Why Drum Drips Matter More Than You Think
Drum drips, also known as low point drains, are installed at the lowest elevations of a dry sprinkler system to collect condensation and trapped moisture.
Their purpose is to capture water before it freezes, allow controlled drainage, protect piping in unheated or exposed areas, and support compliance with NFPA 25 inspection and maintenance requirements.
Drum drips are commonly found in parking garages, attics, vestibules, loading docks, unheated mechanical areas, and long pipe runs where water can settle. When properly maintained, they play a critical role in protecting the system during winter conditions.
The Risk of Improper Draining
Drum drips must be drained correctly. Opening the wrong valve or releasing air pressure too quickly can create serious problems.
If system pressure drops too low, the dry valve can trip. When that happens, water floods into piping that is not designed to hold water in freezing conditions. The result can be burst pipes, flooding, and a disabled fire protection system.
Because of this risk, NFPA 25 limits routine draining of low point drains to qualified personnel who have been trained on the specific system. In many buildings, general maintenance staff do not meet this qualification.
Improper draining is one of the most common causes of winter sprinkler failures, and it is also one of the most preventable.
High Risk Areas Often Overlooked
Certain parts of a building are more vulnerable to freezing than others. Entryways, vestibules, and transition zones between heated and unheated spaces are among the most common failure points.
These areas experience frequent temperature swings, cold drafts from doors opening and closing, limited insulation, and long or exposed pipe runs. Moisture collects easily and freezing happens fast.
When a failure occurs in these spaces, it often leads to flooding at building entrances, electrical hazards, blocked access, and operational disruptions.
Why Winterization Matters
Many freeze related failures do not show up until temperatures rise. Ice expansion can temporarily seal a rupture, hiding the damage until the system refills or activates.
A professional winterization service helps reduce this risk by safely draining drum drips, verifying valve operation, checking air pressure, inspecting freeze prone areas, and identifying hidden low points in the system.
Winter conditions put extra stress on dry sprinkler systems. Proper preparation helps protect your building, your fire protection system, and the people who rely on it.
