Resideo ZD18X16TZ Damper R-448A This technical kit is engineered

This technical kit is engineered specifically for reverse acting actuators and is used to replace the legacy Gradutrol relay with a modern positive positioner

notably consistent with Lennox 7021-9450 and Armstrong 40404-003 units

Direct OEM Compatibility: Specifically engineered for Heil Quaker and ICP families

Designed to handle dual primary voltages of 240V or 480V

this kit is specifically engineered to provide a 9-13 PSI spring range

Resideo ZD18X16TZ Damper R-448A This technical kit is engineeredThe Resideo ZD18X16TZ is a high performance rectangular zone damper engineered for heavy duty forced air zoning. Built with a rugged extruded aluminum frame and parallel blades, this 18" x 16" unit delivers low leakage performance, ensuring precise airflow control across multiple zones. The integrated 24Vac synchronous motor is mounted on the 16" side and features a power closed spring return open configuration, providing a fail safe normally open