- ComfortNet Communicating System compatible - Heavy duty stainless-steel tubular heat exchanger - Stainless-steel secondary heat exchanger - Self calibrating modulating gas valve auto-configure for each installation - Durable Silicon Nitride igniter - Quiet variable speed induced draft blower - Uses ComfortNet communicating, two-stage or single-stage thermostats - Self diagnostic control board with constant memory fault code history output to a dual 7 segment display - Color coded low-voltage terminals with provisions for electronic air cleaner and humidifier - Efficient and quiet variable-speed airflow system gently ramps up or down according to heating or cooling demand - Multiple continuous fan speed options offer quiet air circulation - Auto Comfort and enhanced dehumidification modes available - Cabinet air leakage (QLeak) = <2%