The heat exchanger (1) has at least 2 heat exchanger stages (2,3), each having a separate inlet flow (4,5) and a separate outlet flow (6,7), the inlet flows obtained by dividing a main entry flow (8) and the outlet flows combined to provide a main exit flow (9). The heat exchanger stages may have similar size heat exchange surfaces, one of the heat exchanger stages having a latent heat store, with a valve allowing the inlet flow to at least one heat exchanger stage to be blocked.
展开▼