The present invention pertains to a synthesis gas heat exchanger unit with one synthesis gas radiant cooler (1), two synthesis gas convection coolers (23), one crude gas-clean gas heat exchanger (4), one crude gas-inert gas heat exchanger (5), and one dust separator (11). These devices are preferably arranged vertically or slopingly. The crude gas heat exchangers (4, 5, 23) are designed as single-flue, double-flue or multiple-flue heat exchangers. They are elastically supported via claws (10) and are equipped with an electric heater (9). A soot blower system (13) is associated with each flue (4.1, 4.2) as well as (5.1, 5.2) and right hand flue and left hand flue (23.1, 23.2) at the crude gas inlet. Soot blowers (31) are likewise provided on the connection lines (2, 6), and mass flow controllers (7) are provided in the lower connection lines (6).