Why is my freezer getting warm?

#5 PROBLEM: The temperature is too warm.
LIKELY CULPRIT: The defrost thermostat needs to be replaced if its contacts aren't properly functioning. The normal freezer temperature is between 0ºF and 5ºF. Make sure it wasn't accidentally adjusted to a warmer-than-desired temperature.

All this is further explained here. Besides, why is my freezer warm?

Some freezers use a condenser fan to cool down refrigerant before it enters the evaporator. Clean the condenser coils if dirty. A failed electronic control board or a bad thermistor (also known as the temperature sensor) can also cause your freezer to warm up.

Beside above, how do you know if your freezer is going bad? Signs Your Refrigerator Is About to Die

  1. Your food is spoiling before its expiration date.
  2. Your freezer is too cold.
  3. You can hear the motor.
  4. The back of the fridge feels hot.
  5. Your electric bill goes up unexpectedly.
  6. You're seeing condensation or frost.
  7. You have the fridge-repair guy on speed dial.
  8. Your fridge is more than 10 years old.

Thereof, should the back of the freezer be hot?

The condenser coils should be warm/hot as this is where the refrigerant condenses back from a gas to a liquid (releasing absorbed heat from the fridge / freezer cabinets) before going back into the compressor, to start the cycle again.

Why is my fridge warm but freezer cold?

If the refrigerator freezer is cold but the refrigerator is warm, the evaporator fan motor might have failed. Every refrigerator has a set of coils called an evaporator. If the evaporator fan is running, the damper door is open and no air is coming out. The evaporator may be frosted up caused by a defrost problem.