I just bought this from Lowe’s . Does it comes with built in surge protector? Or should I put external surge protector if unit does not have built in?

We do not recommend connecting a refrigerator or freezer to a surge protector. The compressor is sensitive to temperature and current overloads, and will shut itself down with a surge. A surge protector will override this system, and if there is a power surge, your refrigerator may not restart. ^Daphane