Home furnaces are quieter than ever utilizing variable capacity burners. ECM and variable speed blowers also contribute to quieter operation while producing increased airflow. Furnaces that run at lower speed and capacity are quieter, more efficient, and produce a higher comfort level. Carrier Infinity Series Furnaces are one of the quietest gas furnaces you can buy. That means you can enjoy warm, winter heating at a sound level somewhere between a conversation and a whisper (but closer to a whisper), thanks to variable-speed components, intelligent operation and insulated cabinet.