How often should the air pressure in a pre-action or dry valve used to protect a freezer or cold storage area be checked and compared?

• A. Weekly
• B. Monthly
• C. Quarterly
• D. Semi annually

Answer: (B)

Air pressure in dry and pre-action systems is what keeps the water-filled portion from moving until a proper activation signal is present. Checking and comparing this charge regularly ensures the system remains sealed and charged at the correct level, ready to release water when needed and not prematurely.

The monthly frequency is a practical compromise: it catches leaks or slow pressure loss that could develop from fittings, valves, or air lines without creating an overly burdensome maintenance task. You’ll read the current pressure, compare it to the baseline when the system was last charged and to the acceptable tolerance, and look for any downward trend. If the pressure is out of tolerance or dropping over time, you’ve got a defect or leak to address before it could affect performance.

Checking it weekly would be unnecessarily burdensome for most facilities, while quarterly or semi-annual checks risk missing slow leaks, which could compromise the system’s ability to hold back water and delay activation in a fault condition. This is especially important in freezer or cold storage areas where reliable protective operation is critical.