While I haven’t personally tried making beet chips in a dehydrator or an air fryer, I believe it should be possible with some adjustments:
For a dehydrator: You can try slicing the beets thinly and placing them on the dehydrator trays. Set the dehydrator to a low temperature (around 135°F or 57°C) and let the beets dehydrate until they are crisp, which could take several hours depending on the thickness of the slices.
For an air fryer: Preheat the air fryer to around 325°F (160°C). Place the beet slices in a single layer in the air fryer basket, making sure they are not overlapping. Cook them in batches if necessary to avoid overcrowding. Cook for about 15-20 minutes, flipping them halfway through, or until they are crispy.
Remember to keep an eye on them as cooking times may vary depending on the model and size of your dehydrator or air fryer. Let me know how it turns out if you give it a try!