Vaillant 0020210464 heat exchanger

A genuine Vaillant replacement part, this heat exchanger is for ecoTEC Plus and ecoTEC Pro 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 while a secondary heat exchanger is present only in combis and allows the heat to be transferred between closed systems.