There are two variants of heat exchanger, which are the primary heat exchanger and the secondary heat exchanger. The primary heat exchanger, installed within almost all boilers enables the heat transfer from the burner to the water within the system. The secondary heat exchanger, which are predominatly only present in combi boilers, enables the heat to be transferred from one closed system to another.
![Worcester Plate Heat Exchanger (10 Plate) 87161066860 [6861]](http://allgasltd.com/cdn/shop/products/Worcester_10_plate_heat_exchanger_87161066860.png?v=1682074748&width=1445)