Precision Calibration: Factory-set at 325°F M/R for accurate thermal protection and failure prevention

Whether you are dealing with carbon buildup or a cracked insulator

you should find near-zero resistance between terminals 1 and 2 (normally closed)

Is hardware included for the condensate line connection

These OEM replacement valve packing parts are the standard for contractors managing legacy Honeywell pneumatic hardware

Maxitrol TD121 Temperature Selector 30067439-890 Precision Calibration: Factory-set at 325°FThe Maxitrol TD121 Temperature Selector is a critical control component designed for Selectra Series 21 and 31 electronic gas modulation systems. Specifically engineered for make up air heating and indirect fired units with atmospheric burners, this remote selector provides precise setpoint management within a 55 90 degrees F range. Unlike standard thermostats, the TD121 functions as a remote setpoint adjuster, communicating directly with the A1010 or