Carrier HH12ZZ185 Limit Switch 321702-401 allowing for granular modulating valve

allowing for granular modulating valve adjustments that stabilize hydronic flows

Fenwal uses color-coded leads or markings to signify temperature ratings

leak-free integration with various gases and liquids

the AH23A020 ensures positive shut-off in demand-heavy environments like fan coils

The equalizer line must be connected to the suction line near the sensing bulb to ensure the valve references the correct pressure for superheat adjustment

Carrier HH12ZZ185 Limit Switch 321702-401 allowing for granular modulating valveThe Carrier HH12ZZ185 Limit Switch (part number L185F 40) is a critical OEM HVAC replacement part designed for high limit thermal protection in furnace and air handling units. This normally closed (NC) switch functions as a primary safety mechanism, monitoring internal temperatures to prevent heat exchanger damage. It features a fixed set point that opens the electrical circuit when temperatures reach 185F and automatically resets once the system