Aprilaire 4977 Relay 322838-752 Standardized Connections: Standard 1/2 inch

Standardized Connections: Standard 1/2 inch NPT female threads provide easy integration with existing copper or PEX piping manifolds

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

and LFSH1434 mixing valves

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

Technicians should verify if additional vibration isolators or specific bearing inserts are required for the specific job

Aprilaire 4977 Relay 322838-752 Standardized Connections: Standard 1/2 inchThe 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