What should the gauge on a quick opening device indicate compared to the gauge on the system side of the dry pipe valve?

In a dry pipe fire protection system, a quick opening device is designed to rapidly fill the piping system with water to improve response time in the event of a fire. The gauge on the quick opening device should indicate a pressure within a range of plus or minus 10 PSI compared to the gauge on the system side of the dry pipe valve.

This range is crucial because it allows for normal variations and fluctuations in pressure that can occur due to changes in temperature, water demand in the system, or other operational conditions. The pressure indicated by both gauges should closely align, showing that the quick opening device is functioning correctly and that it can effectively allow water to flow quickly when needed.

If the pressure indicated were zero or significantly different from the system side gauge, it would signal a potential issue with the quick opening device or the system itself, which would warrant further inspection and maintenance. Therefore, maintaining a consistent and relatively close pressure measurement helps ensure that the fire protection system will operate effectively in an emergency situation.