Buderus developed the full three pass system to increase the heat transfer and efficiency of boilers. This design allows more heat to be transferred during all three passes, unlike conventional boilers that only use one pass to transfer heat. This system maximizes the total possible heat available with the lowest fuel consumption possible. To greatly decrease standby loss Buderus has manufactured a 3½" and 4" thick thermal insulation.

• High Efficiency - Combustion Efficiencies Up To 88%
• Thermostream Design Eliminates Thermal Shock
• Flexible, Corrosion Resistant GL-180M Cast Iron
• Full Swing Reversible Burner Door for Excellent Serviceability
• Eliminates the need for bypass loop or shunt pump
• No additional requirements for firing with 2-stage or full modulation burners
• Suitable for operation with oil or gas