My Bosch GSU340 freezer is 5 years old and the temp is not getting colder than 10 degrees, the recommended temp is 18 degrees. Does anyone have any idea of what could be wrong and the cost of repairing it
As it’s a frost free unit, it may be choked with ice.
Try a complete defrost over 24 hours and try it then, if it is still not working correctly or fails again fairly quickly then it could be one of many things to be honest.