title_body: How can I prepare an espresso machine for long-term storage
upvoted_answer: If you live in a hard water area then clean using a citric acid solution and make sure that the pumps are then empty of water.
  
  You could if it's easy remove the gasket seal (if there is one) which sits on the metal fine filter where the coffee is pumped through, this is to avoid any residue drying and gunk/mould forming on the seals.
  
  It may depend on your model how easy access some of this. If you have a bean to cup then you'll need to clean the waste bin and empty the bean hopper.
  
  Finally store it in the original box, somewhere that isn't humid and you should be fine.
  
  When you fire it up again, you'll need to pump water fully through (again you could use a citric acid solution) and restore the gasket seals. I can't think of anything else you could do.