Key Benefits: Precision Thermal Safety: Features a 165F-CO trip point to prevent heat exchanger damage and a 135F-CI reset for automatic system recovery

protecting sensitive HVACR electronics from intermittent faults

While some designs overlap

The A-4000-613 is rated for a maximum internal pressure of 150 psig

Demand Defrost Logic: Optimizes cycle frequency based on actual atmospheric conditions rather than fixed intervals

Resideo RT850T-347 Relay 320788-703 Key Benefits: Precision Thermal Safety:The Resideo RT850T 347 Relay is a heavy duty solid state relay engineered specifically for controlling line voltage resistive loads in electric heating applications. Featuring a built in 24 V transformer, this unit simplifies the control of baseboard heaters, radiant ceilings, and duct heaters from a low voltage thermostat. The TRIAC switching ensures 100% silent operation, eliminating the mechanical clicking common in traditional contactors, making