Aprilaire 4977 Relay 322838-752 monitoring the common circuit to

monitoring the common circuit to detect excessive current draw or high internal temperatures that could lead to winding failure or a locked rotor condition

Always verify the probe length against the manifold clearance to ensure proper seating within the water column

and LFSH1434 mixing valves

Simplified Troubleshooting: Features clear diagnostic paths for testing multi-stage electric heating circuits and verify proper relay engagement

engineered to interrupt the electrical circuit and terminate the heating cycle when internal plenum temperatures reach the 155°F open setpoint

Aprilaire 4977 Relay 322838-752 monitoring the common circuit toThe Aprilaire 4977 Relay is a high performance 24v Coil DPDT Relay designed for seamless integration within advanced HVACR systems. This versatile double pole double throw relay serves as a critical HVAC control component, allowing for the simultaneous management of two independent circuits. Engineered for Aprilaire humidifiers and air cleaners, this 24 volt switching relay ensures precise electrical isolation and reliable secondary hardware