Siemens Building Technology GRD221.1U Actuator 321894-709 The spring-loaded mechanism and adjustment

The spring-loaded mechanism and adjustment handle are isolated from the liquid stream

suggesting internal component failure

It is specifically compatible with the S1-2HK16501506 heater kit

if the circuit is open or resistance is out of manufacturer-specified range

ensuring a consistent spray pattern that minimizes soot buildup and prevents electrode fouling

Siemens Building Technology GRD221.1U Actuator 321894-709 The spring-loaded mechanism and adjustmentThe Siemens Building Technology GRD221. 1U Actuator is a specialized 120V fire and smoke damper actuator designed for critical life safety HVACR applications. As a veteran grade two position spring return actuator, it delivers 30 lb in of torque, ensuring reliable open close operation for smoke control and combination fire smoke dampers. Built to exceed the rigors of UL555 and UL555S standards, this unit provides a nominal 30 second drive time and a