Gas and Oil Furnaces MODEL XL90 Two-stage heating for gentle warmth XL Two Stage Wether it's gentle warmth when it's just a bit chilly, or high-performance heating for those freezing days and nights, the XL90 provides two stages of comfort so your system meets your expectations for total home comfort. MODEL XL90 features: Efficient performance The XL90 is rated with a 92%+ AFUE. Flexible heating Two-stage heating helps prevent temperature swings. Durable construction Materials for all components are tested again and again for long-lasting performance and reliability. Better indoor air Add a Trane Air Cleaner to your system for filtering that removes more dust, pollen and other irritants throughout your entire home for a cleaner, healthier, more comfortable home.