Ericsson was not discouraged by the failure of the caloric ship and patented a number of improvements during the years 1855-1858. These experiments cumulatated with his improved Caloric Engine an open cycle machine using a power piston and a supply piston, fitted with valves. This engine proved an immediate success with over 3000 being sold with in three years. This machine was sold in sizes of 8 inches to 32 inch cylinder diameters.

John Ericsson became interested in Solar power. Finding that his small caloric engine was not suitable on account of the valves he developed, around 1872, a displacer type (or Stirling) engine to work with a parabolic reflector; intended for use in the sun-burnt lands of the pacific coast for irrigation purposes. The engine was not taken up for use as a solar powered machine however, but his business backers persuaded him to patent the design, in 1880, as a pumping engine, heated by coal wood or gas. The engine was first built by the Delameter Iron Works and later by the Rider-Ericsson Engine Co. in sizes 5 inch to 12 inch cylinder diameter. This was to be the last air engine developed by John Ericsson.