Functional Devices RIB2401C-N4 Relay 340793-762 The Carrier HH18HA420 Auto Limit

The Carrier HH18HA420 Auto Limit Switch is a critical HVAC safety device designed to monitor internal furnace temperatures and protect the heat exchanger from thermal stress

Precision Superheat Control: Maintains optimal evaporator efficiency to maximize HVAC system performance

and high-capacity gas equipment

the 100327628 is the official direct replacement for the legacy 100277759 relief valve

managing critical sequences for heating elements and auxiliary fan controls

Functional Devices RIB2401C-N4 Relay 340793-762 The Carrier HH18HA420 Auto LimitThe Functional Devices RIB2401C N4 is a heavy duty Enclosed TriVolt Relay engineered for demanding HVACR applications requiring NEMA 4X protection. This versatile power relay supports 24 VAC DC, 120 VAC, or 208 277 VAC inputs, providing maximum field flexibility for building automation and industrial control systems. The SPDT configuration features a 20 Amp rating, making it ideal for managing motor loads, lighting circuits, and high wattage resistive