The H-22a was a converted H-22 coke car. The H-22 was originally built with clam shell doors but were converted to saw tooth doors as shop repairs were required. This conversion did not cause a class change so either type of doors could be found at various times. The conversion to class H-22A began in 1923. This conversion replaced the coke slats with solid panels above the belt line and placed the car on 70-ton Crown trucks. Carrying capacity was increased to 140,000 pounds of coke. 3671 H-22A's were converted by 1930. After 1930 the H-22 class cars were scraped instead of any further upgrades.