brazier vs water heater

brazier

noun
  • An upright standing or hanging metal bowl used for holding burning coal for a source of light or heat. 

  • A worker in brass. 

water heater

noun
  • An appliance for heating water above its ambient temperature, generally for domestic use. 

How often have the words brazier and water heater occurred in a corpus of books? (source: Google Ngram Viewer )