Following the successful introduction of the Finnish-built H3s, five similar engines with larger boilers were ordered at the beginning of 1907. These were delivered from 1907 to 1908, numbered 471–475 and classified H4.
Nos. 471–475 were originally saturated steam compound locomotives with piston valves as well as Mellin starting valves and, except for their larger boilers, otherwise very similar to the H3s with. They were equipped with gas lighting and built as wood burners but, as typical in Finland, were at times coal burners. They were rebuilt as simple engines in 1925–29 with new cylinders and superheating. After this change, they were re-classified H5 and became class Hk3 in 1942.
Initially, the H4s were allocated to Helsinki and Viipuri but were ousted by H8s and H9s to secondary main line duties in the 1920s. Their history subsequent to the rebuilding as class H5 is recounted in the next section. All the former H4s were withdrawn in 1964.