[Arrowhead1952]

Defrost timer or defrost heater or both. If it is still under warranty call for service. If not the parts are easy to replace.

That is the correct reply. I had to replace both on our previous fridge. Also, the defrost fan may not be moving enough air to keep the fridge area cold.

[djf]

Well, now that I have the vents unblocked and know the operational characteristics, I will watch and see if it happens again.

If it does, then I have a parts problem.

If not, then it’s fixed!
Yay!

Sometimes ya gotta be happy with little victories, eh?

[Calamari]

Have done this twice to our kitchen fridge for about $100 each time. Less expensive than buying an new fridge!