The stem and outside temperature don't matter (within reason) really, it's the temperature inside the load that matters, that's what Air tries to control. Adding (or removing) insulation in the outer walls of your house shouldn't effect the temperature inside since the thermostat will simply run more power to the heater to compensate. Same here. Not a good configuration, but not fatal.
If it's vaping normally, and it sounds like it is, it's working correctly no matter what the outside temperature is as far as it's concerned.
Don't mess with that 'yellow tape', it's Kapton (very tough, high temperature) and there for important reasons (protecting the wiring). This is one of the reasons you don't want to mess with opening it up, those wires are very easy to damage....even with the taps. The unit can fail if the tape is not correctly in place. They are not some sort of warranty indication but a critical part of the system. The temperature sensor is deep inside the oven assembly, 'thermally' very near the cup. This is the two smaller wires under the heater, the larger ones are the heater proper. It, as it should, senses the load not outside temperature.
You unit is no doubt no different than the rest of ours, which see only minor issues. Something about your technique may be responsible. I suggest a review of this thread. Debris should be going down those holes, as you've discovered it comes out the bottom of the oven and piles up on the works there. Smelling bad and robbing heat/power. Avoid loose herb on the face of the cup and for sure don't use the edge of the stem to grind it up and force it down the holes. And keep and eye below, blowing it out to avoid accumulations and you should be fine.
Having a backup is just sound thinking. There are no guarantees of no inconvenient failures. In fact it often invites them in a strange way. Guys with Crafty and Plenty (top of the line in many/most guys eyes, German made and costing many times what Air does) seem to be having out and out breakdowns at about the normal rate? It's a mater of numbers, if you have say two 95% reliable vapes instead of one instead of having fatal failure goes from five in 100 to one in a thousand. From once a month or more to every few years. Every serious vaper should have a backup. I think of a different type that's also fun to use in it's own right. Perhaps time to consider a VG or perhaps a personal favorite of mine, Vapman (Swiss made even). Both half the price of the Air and excellent vapes in their own right that don't need electricity.
Your call, of course, but were I you I'd be cleaning the Air not sending it in and thinking about a backup vape for the eventual time you really need one? It might take several passes to get enough of the debris out, the oven is probably packed below. Heat/cool cycles in use should help there. Also consider whole buds, 'hamster style', an extra flat screen or some of the other techniques discussed here to change the debris situation. It should not be happening but I don't see how that's the vape's fault.... I'm confident yours is not different enough to cause that.
Regards and best wishes.
OF
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