steam generator vs warmer

steam generator

noun
  • a type of boiler fitted in a diesel locomotive or another rail vehicle, which provided steam heating in steam-heated passenger trains that had previously been hauled by steam locomotives. 

warmer

noun
  • Something that warms, such as a heater or a soup. 

  • An introductory activity, for example in a lesson, to stimulate interest in a topic. 

  • A piece of clothing for warmth, such as a bodywarmer or leg warmer. 

How often have the words steam generator and warmer occurred in a corpus of books? (source: Google Ngram Viewer )