With cold weather comes the risk of impaired fire protection because of the low temperatures freezing water in the sprinkler piping and other system components. Frozen fire prevention sprinkler systems can result in fire loss due to damaged detection or extinguishing systems, as well as extensive water damage to the building and contents caused by burst piping.
As the temperatures begin to rise above freezing and the ice begins to thaw, further damage occurs with breaking of valves, piping, and, of course, water damage.
Freeze-ups in automatic sprinkler systems are a result of insufficient heating in a building caused by things such as:
- Failure of the heating system
- Insufficient insulation material in walls/ceilings
- Cold air entering via broken windows
- Inadequate antifreeze in the system
- Cracks in a wall, and other physical deficiencies.
Fortunately, there are a few things that you can do in order to prevent wet and dry pipe systems from freezing during cold weather.
Wet Pipe Systems
These sprinkler systems have water in the piping at all times, so freezing can occur when there is insufficient heat. Freezing can also occur due to building maintenance defects, like broken windows, open doors, windows, vents, cracks in walls, and loose shingles and siding, among others. The best way to prevent freezing in a wet pipe system is by conducting thorough inspection of the facility before the start of winter. The inspection should include:
- Assessment of attic and floor voids, stair enclosures, basements, wall cavities, building entrances, and plan rooms and ensuring adequate heat can be maintained
- Ensuring that that the pipe work is sufficiently insulated and protected from freezing – especially in places where piping is exposed to outside temperatures
- Keeping all openings closed when not in use – doors, vents, and windows
- Checking the facility for cold air leaks around doors, window frames, external walls, and even the roof and repairing them
- Ensuring there is sufficient heat reaching spaces in drop down ceilings installed beneath piper work. Basically, the temperature near sprinkling systems should be no less than 40°F (4.4°C).
- If the heating system has to be shut off, the system water should be drained and a temporary fire watch established
- Constantly assessing visible components of the sprinkler system for leaking or distorted sprinkler heads
- Ensuring sufficient anti-freeze solution for anti-freeze solutions
Dry Pipe Systems
These systems do not contain water in their piping, which makes them less likely to freeze compared to wet pipe systems. Still, you can ensure that freezing does not become a problem in cold weather by:
- Draining condensate or water from auxiliary drains
- Keeping the dry pipe valve and riser on the water supply side of the valve sufficiently heated (above 50°F)
- Ensuring there is adequate air in the system, since pressure drops occur in cold weather
In the unfortunate event that your sprinkler system freezes, shut off the Main Control valve to prevent further water damage, and then contact your sprinkler maintenance company immediately.