4 inches and weighing 2

eliminating compatibility concerns

Signal Integrity: Maintains precise communication between low-voltage thermostats and line-voltage components

including the ball bearing insert and the eccentric locking collar to ensure the shaft is held firmly in place during high-RPM operation

the 100109862 is the current manufacturer-recommended direct replacement for the 9004453105 inducer motor assembly

Aprilaire 4851 Relay 30067439-890 4 inches and weighing 2The Aprilaire 4851 Relay is a high performance Blower Activation Relay engineered specifically for seamless integration with whole house humidification and HVAC systems. This critical component allows your HVAC control board to initiate the furnace blower independently of a heat call, ensuring optimal humidity distribution throughout the living space. Designed as a direct Aprilaire replacement part, it facilitates the necessary electrical handshake