The locomotive was primarily intended for heavy shunting duties at Barry Docks and Nos.
5 was used to pull the first passenger train between Barry Docks and Cogan when the line opened on 20 December 1888.
The following year the Class C locomotives arrived and were specifically designed for passenger traffic, at which point the vacuum brake fittings were removed and No.
1 (GWR 699) was withdrawn in April 1931 and sold to Coltness Iron Co Ltd in June 1932; it was cut up on site in March 1962.
4 (GWR 703) was withdrawn in May 1932 and sold to Ocean Coal Co Ltd at Lady Windsor Colliery in Ynysybwl; it was scrapped in 1956.