Dry Systems are a mechanical type of fire protection system that maintains air pressure in in the pipes of the system. These systems are used
when there is an issue with the potential of the pipes freezing such as in a parking garage. On Dry systems there is a dry valve in a heated
area that controls the system. This valve holds back the water until the system loses enough air pressure where the valve can no longer hold
back the water pressure. The valve will then trip sending water flowing through the pipes. The water will fill the system and flow water
through whichever sprinkler head(s) have fused. These systems are to be tested regularly by simulating an air loss on the system which will
then trip the dry valve.
A Dry system needs to be constantly maintained and all low points in the system need to be drained regularly to assure that there is no water
in the pipes that could freeze.