A:
Hi, thank you for connecting with us! Based on what you have described it seems to be the drain hole, and no it should be kept in place during normal operations. When the unit needs to be defrosted, the cap can be removed to allow the water to drain out. Please make sure there is a drain pan under the unit to catch the drain water. We hope this information proves to be of assistance, we are also welcome to receiving any concerns or question you may have via this website’s Q&A forum.
-Best Regards-