Task: Question Answering
Input (English): passage: Many newer units employ automatic defrosting (often called ``frost-free'' or ``no frost'') and do not require manual defrosting in normal use. Although, in some cases, users of Frost Free fridge/freezers have noted ice blocking the vent that allows air into the refrigerator compartment. All refrigerators and/or freezers whether or not frost free, should be defrosted at least every 6 months (or more if you live in humid conditions or if the door is opened excessively). Frost Free units should be defrosted every year, as frost can form on the evaporator covers, which can look unsightly and degrades freezing performance, sometimes to the point of the freezer thawing out due to degradation of defrosting. This can happen when the defrost timer is not set up correctly/malfunctioning or if the heater units or temperature sensors are malfunctioning.
 question: should you defrost a frost free fridge freezer?
Output (English): Yes