All the guys I know (and all are abroad) that do this go at high temperatures. To give an exact temperature is hard as the wax comes in different grades which have different temperatures at which they reach the various critical points.
However............the term dipping is fine but if it is leaving much in the way of visible wax on the boxes its not hot enough. The wax should almost be smoking and the term that (although not used) is more accurate might be frying the boxes in hot wax.
As other posters have alluded too this causes any water in the wood to be expelled, even the air in it expands massively, and once the box is removed from the tank it cools rapidly and draws all the wax still on it into the wood.
They dip the whole box in the wax at once, so its a lot of wax in their tank. Once out it appears bone dry almost immediately and if you are going to paint its best to do it while still hot. My friend in California painted his either with white or silver paint (the silver was a primer type...not sure which) too keep the heat down inside the hive in summer.
Where the paint flaked it was due to too much wax remaining on the outside so they had not been done hot enough.
Properly dipped boxes still looked almost new after 20 years. He had a few that had never been painted that were done by his father many years before and you would have thought them to only be a couple of years old.
Any that still had wax on the exterior were terribly slippy to use and until the bees had joined them on even a modest wind could cause the upper boxes to slide off a hive and tying loads down on a truck was interesting.
Never done it here because, done properly, it is a hazardo0us process and the wax catching fire was a fairly regular event as it was not too far below flash point. They kept the full panoply of fire fighting gear close at hand. Our space is relatively constricted and the potential for a nice vigorous wax fire near a store full of bee boxes is not an insurable risk.
AFB destruction? Yes have heard that gear from AFB hives that is wax fried does not get any recurrence of AFB upon reuse. Is it dead or entombed? Don't know but the practical result is the same.
