Ideal plate heat exchanger kit is compatible with Esprit 2, I-mini, Logic, Isar, Evo, Logic+ and Independent boilers. The heat exchanger transfers heat from a boiler's burner to water. A primary heat exchanger is found in all boilers, using heat from a burner to raise the temperature of the water in the system. The secondary heat exchanger is present only in combis and allows the heat to be transferred between closed systems. This Ideal Domestic Hot Water Heat Exchanger (Plate to Plate) has an Ideal Part Number: 175417. It fits Ideal Isar HE24 (Serial Number From Prefix XF Onwards) Boilers and Ideal Logic Combi 24 Boilers.