Upright is Best

• Freezers should be kept upright when in use, and even when they are being stored. This is because freezers, like refrigerators, contain evaporator coils, compressors and oil to run the compressor. If you lay a freezer on its back, the oil will drain out of the compressor and flow towards and possibly even into the evaporator coils. This means that when you set the freezer upright again, it won't work -- at least not right away.
  
  

Moving a Freezer

• If you need to lay a freezer on its back -- perhaps to move it -- prepare it correctly. Remove all of the food and store it in another freezer. Once it is empty, unplug the freezer and let it defrost completely. It should be thoroughly dry, so wipe it down if necessary. This may take a day or two.
  
  

Safety Issues

• Once the freezer is dry, remove any shelves or other loose parts. Then, secure the doors with duct tape so they don't fly open when you are moving the freezer. Tape the cord to the size of the freezer as well so it doesn't trail along behind and pose a tripping hazard.
  
  

Using It Again

• If your freezer was on its back for a short or even long period of time, do not plug it in right away after setting it upright. Instead, wait for 24 hours, or for at least as long as the freezer was on its back. This gives the oil time to work its way back down to the compressor. It also allows the gas in the coolant time to stabilize.