The 664229R is the manifold tube itself

maintaining factory specifications for safety and airflow management

ensuring long-term switching performance under AFL (40A) and resistive (50A) loads

check the red reset button on the upper thermostat

reducing nuisance trips and diagnostic time

Honeywell TR50-5N Sensor R-449A The 664229R is the manifoldThe Honeywell TR50 5N Sensor is a high accuracy, Sylk enabled wall module designed for seamless integration with Spyder, Stryker, and CIPer Model 30 controllers. Engineered for demanding Indoor Air Quality (IAQ) monitoring, this multi sensor device tracks CO2 concentration, relative humidity, and temperature through a single two wire communication bus, significantly reducing terminal labor and cabling costs. Its NDIR CO2 sensor provides reliable, long