1. Ensure that the freezer has the correct ventilation, as per below.
Each Side: 20mm
Above: 20mm
Rear: 100mm

2. Make sure the freezer can get adequate fresh air to allow correct operation and cooling, don't box the freezer in with incorrect ventilation or airflow. 

3. Ensure that there is no direct sunlight contacting the freezer, no glass door fridge or freezer is designed to handle direct sunlight - If the freezer is in a position where it receives direct sunlight the warranty will be voided. 

4. This freezer is rated to handle ambient temperatures up to 32°C, ensure the unit is not in a location that exceeds this rating. 

5. Check what the manual thermostat is set to, the higher the number the colder the freezer will operate.  
If you have this maxed out, the freezer will eventually have ice build-up. which can impede the cooling of the unit making it warmer than intended - we recommend setting this between 2 and 3.

6. Check to make sure the compressor turns on correctly - you should be able to hear it humming away at the rear of the unit.