Refrigerators can start smelling pretty funky after a few years of use. If you want to rid your fridge and freezer of lingering smells once and for all, this deep cleaning regimen will get the job done. As this video from the Consumer Reports YouTube channel demonstrates, the first thing you need to do is remove everything from your fridge and freezer. If your fridge smells really bad, you'll need to find overnight storage for your food elsewhere. Or try to use up all of the food in your fridge before attempting this. Once the food is out, remove all of the shelves and drawers, then wash them with hot, soapy water. If they're really bad, a mixture of bleach and water will do the trick. Now mix one cup of bicarbonate of soda with 3.75L of water, and use it to wipe down every surface inside of your fridge and freezer. After you finish wiping everything down, unplug your fridge and leave the doors open overnight. The next day, everything should smell fine and you can put your food back inside.
If that doesn't solve the problem, though, you might have to take it a step further. Keep your fridge unplugged, and open the panel in the back of your freezer so you can access the evaporator coils. You may need a screwdriver to do this, and make sure you unplug any wires you find. Now spray the coils with warm, soapy water, and lay a paper towel underneath them to catch the runoff. After that, wipe down the coils with a microfibre cloth and put everything back together after they air-dry.
How to Clean a Smelly Fridge [YouTube]