Aprilaire 4977 Relay 321894-706 This is the recommended direct

This is the recommended direct replacement

The Robertshaw 1980-018 utilizes a high-grade copper and nickel alloy core for maximum millivolt output and electrical conductivity

reducing compressor load and improving system stability

Reliable Cold Starts: High-amperage output ensures proper hot surface igniter glow for consistent ignition

this reversible filter drier is fully compatible with R-410A

Aprilaire 4977 Relay 321894-706 This is the recommended directThe 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