De Dietrich 200004871 GT 220 intermediate section

This part is an intermediate section for a heat exchanger of the De Dietrich GT 220 series. In a sectional heat exchanger, intermediate sections sit between the front and rear end sections to form the core of the heat transfer assembly. Such sections contain the flue gas passages and water channels; heat from the flue gases is transferred through the section walls to the heating water that circulates through the boiler. The number of intermediate sections determines the total heat output of the exchanger. When selecting an intermediate section of this type, the critical parameters are the physical dimensions (height, width, depth) and the connections that must match the existing end sections and manifold. The material of the section – typically cast iron, aluminium alloy, or stainless steel – must be compatible with the boiler’s operating conditions, particularly in condensing appliances where condensate corrosion can occur. Gaskets between sections must be replaced whenever the exchanger is dismantled; the correct gasket type for this model is essential. Common issues with such sections include scaling on the water side due to hard water, soot accumulation on the flue gas side from incomplete combustion, and leaks at the section joints. During replacement, inspect the mating surfaces for damage and verify that the section aligns correctly with the turbulators if they are fitted in the flue ways.