The DXL Two Stage Condensing Exhaust Economizer is specifically designed to recover sensible heat from within the exhaust and, more importantly, to also recover additional valuable latent heat as the exhaust is condensed. What makes the DXL Boiler Economizer unique is that it recovers heat in two stages. The first stage will preheat boiler feedwater and the second stage will preheat boiler make-up water. Final exhaust temperatures leaving typically range from 120°F – 170°F. This recovered heat will be transferred to feedwater and makeup water, thereby increasing the overall efficiency and lowering the fuel demand.