I have a W/House fridge a502 model Frost Free.the outlet pipe was blocked I dropped the control box in the refrig section and a plastic cover fell down from somewhere.I cleared pipe and reasembled but I cannot for the life of me find where this cover goes it measures about 80mmx45mmx50mm no screw holes it looks like a air deflectorof some sort the fridge is approx 25 yrs old Can you please help .