A new line of pressure relief doors is available. The doors function to prevent ductwork from imploding or exploding in the event of excess pressure. The PZ10 (positive) and the VT10 (negative) pressure relief doors are designed to open automatically 1-inch w.g. above normal operating system pressure. At the specified setting, the doors permit immediate and unrestricted neutralization of the pressure differential between the inside and the outside of the ductwork system. The pressure relief doors have a field-adjustable nonmechanical latch.

A.J. Manufacturing Inc., 1217 Oak St., Bloomer, WI 54724; 800-328-9448; www.ajdoor.com

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