ORIGINAL: pe reivers

that is A-OK
now going from cold and humid to hot and dry is not that easy, because cold air cannot contain much water.

Some reasoning may be in order.

If you heat cold humid air to hot, it will be hot dry air.

Since water content is the same, I think only the temperature increase which reduces the oxigen amount per unit of volume is important in this question, and thus the needle has to be leaned out, despite the fact that humidity is lower.