All connections and troubleshooting points located in one convenient place, the easy-access master terminal board. Units feature through-the-base utility connections capability. Access panels have easy-grip handles and no-strip screw feature. Newly designed terminal board facilitates simple safety-circuit troubleshooting and simplified control box arrangement. Quiet and efficient operation is provided by belt-driven evaporator fans. Energy Star-qualified units feature field convertible airflow (field accessory supply duct kit required for 150 size model only), high- and low-pressure switches, and scroll compressors. Scroll compressors have internal line-break overload protection. Factory-installed options include medium- and high-static indoor fan and economizer options.