Refrigerators are expensive and a pain to replace if you need to do it in a hurry (it happened to me once).
Here are some tips that will really help you out. Its easier to care for your fridge than it is to replace it.
IMPORTANT: Before cleaning the condensor coils, unplug the refrigerator to avoid a shock hazard.
The condensor coils dissipate heat. If dust and debris accumulate around the coils, your refrigerator may not be able to cool properly, it may run continuously or it may stop completely as a result of an overheated compressor.
Rear-Mounted Coils
You should clean rear-mounted coils once a year. Unplug the refrigerator before cleaning. Refrigerators are heavy, never tip one forward or backward. Never attempt to move a refrigerator without help.
Vacuum or brush the coils. If coils have a filmy build-up, use warm soapy water to clean them. Take care not to spill or drip water onto the components of the refrigerator.
Floor Level Coils
You should clean floor level coils at least twice a year. Unplug the refrigerator before cleaning. Vacuum or brush the coils.
Remove the grill from the front of the refrigerator and use a vacuum with a wand attachment to remove any dust and debris. The grill should snap off and on. Pull firmly toward and possibly upward to remove the grill. If it does not come off with a modest effort, check for screws or retaining clips that may hold it in place.