How does the air pressure in a dry pipe system typically compare to the system's water pressure?

In a dry pipe sprinkler system, the air pressure is specifically designed to be higher than the water pressure to ensure the system's proper functionality. By maintaining the air pressure 20 PSI higher than the water pressure, the system can effectively hold back the water until activation is needed. This difference in pressure helps prevent premature water discharge and ensures that the system remains in a charged state until the fire detection system signals an alarm, triggering the release of water.

The choice to have the air pressure set higher than the water pressure is crucial in achieving the intended operation of the dry pipe system, allowing for a quick response when the system is activated. Maintaining this pressure differential also helps in mitigating the potential issues associated with condensation and freezing in the pipes.