Kenmore Refrigerator 795.71603012 Sounds like someone knocking at the door

[kau1]

Model Number

795.71603012

Brand

Sears Kenmore

Age

6-10 years

Kenmore refrigerator (no ice maker) knocks a few times then stops, once or twice a day, and scares the heck out of my dog, who thinks someone is at the door. The sound seems to come from the top part of the unit.
Please help. Thanks!

 

[Jake]

Did this just recently start when the weather got warmer? Is the refrigerator running when it does this noise? Or has the refrigerator cycled off and its dead silent when it does this noise?

Jake