How to Winterize Commercial Fire Sprinkler Systems
Fires are suppressed on commercial properties by fire sprinkler systems. A fire sprinkler system is required by building codes as mandatory safety equipment. Besides being inspected yearly, the National Fire Protection Association recommends that they be winterized yearly as well. This holds true for both wet and dry fire sprinkler systems.
There are two types of fire sprinkler systems and both require yearly winterization. The pipes in a wet system are filled with water, fed by a consistent water supply. The pipes in a dry system contain pressurized air. This air is released when a sprinkler head is triggered to open. It causes water to flow from a storage tank.
To winterize a wet fire sprinkler system:
- Check that each sprinkler valve is in the "on" position.
- Decrease the building temperature.
Do not set it to lower than 40 degrees Fahrenheit if the building is not going to be occupied for several days. - Check that the insulation covering the pipes in the ceiling is adequate
- Prevent heat loss by keeping attic doors, access points and all doors to the outside closed.
- Check that there is enough antifreeze in the water to prevent freezing in exposed pipes.
- Use heat tape to protect pipes that are exposed to temperatures below 40 degrees Fahrenheit.
- Plug the heat tape into an indoor electrical outlet.
- Inspect the heat tape daily to assure protection remains in place.
To winterize a dry fire sprinkler system:
- Shut off the water source valve
- Shut off the air compressor
- Start at one end of the system to drain each valve.
- Close the top valve.
- Allow water to drain by opening the drum drip (bottom) valve
- Reset the drum drip valve to its original position.
- Open the top valve.
- Close the bottom valve.
- Repeat steps four through eight for each valve on the system.
- Turn the air compressor on.
- Set the valve room temperature to no lower than 40 degrees Fahrenheit.
- Check that the air compressor is heated, as that will protect the valve from freezing.
If it is not, put a small electrical heater in the valve room - Check the air compressor heat functionality, or the room heater if used, daily.
It is necessary to be sure that the valve protection is operating properly.