Hi Kev, not really my forte as refrigeration is a seperate engineer but I will try to help.This one is a frost free machine.Does the machine turn itself off and defrost.?Is there ample airflow, especially as we have warm weather,make sure you have a vent in the plinth and above the machine.Are the doors closing okay, not just the decor doors.The other thing,it could be the thermostat or probe.It will turn off every 12 hours to defrost the evaporator and it may stay off too long.If the engineer did not come out long ago and you have a guarantee on the labour etc, keep ringing, It looks as if there is a fault. Hope this helps, All the best
Foxy
August 2008