Although sufficient for the Southern Railway's needs, the N class was an ideal test-bed for experiments with new steam technology. The first experiment entailed fitting a Worthington feed pump to No. A819 in 1924. The trial was moderately successful, and the pump remained in use until removal in 1927. In June 1930, No. A816 was withdrawn from service for the application of experimental Anderson steam conservation equipment at Eastleigh Works. This was designed by a Scottish marine draughtsman, Mr. A.P.H. Anderson, who proposed the use of a fan system to condense spent steam and improve draughting of the fire on long-distance runs in regions with poor access to water.