By using indoor/outdoor reset, DeDietrich boilers can modulate to lower temperatures than most other cast iron boilers. The result: extraordinary annual efficiency as well as greatly increased control and ease of installation.

Boiler temperatures can go down to 85°F (GT300) and 105°F (GT400 & GTE500) without damage to the castings. The design and quality of the cast iron provide control and operating efficiency, thus assuring lower operating costs and longer life. Low operating temperature capabilities make the GT series ideal for water to air heat pump or 2 pipe systems.