jray3 wrote:Sorry to be flippant Aero. I spent Christmas skiing north of you in Durango. It felt like my parched amphibian skin would split open, but the chapped lips have finally healed.
One of my favorite haunts used to be Purgatory Ski area. Much more fitting name than it's current Durango Mountain moniker IMO.
I'm not a refrigeration engineer either. Just a Physics major (the science of engineering). I'm fairly certain that no one here cares about the humidity discussion in detailed scientific terms. They just want repeatable good results. Just a couple of points then my end of it rests.
1. The tables and graphs are apples and oranges compared with the systems working in our cars. Many factors, but just a couple for examples.
1. The AC coil in a vehicle is very small which leads to reintroduction of significant amounts of moisture to the airflow condensed on it as air recirculation continues.
2. Occupants add significant humidity to the mix breathing etc.
3. Refrigeration units suffer considerable stress when operating in a very cold environment (it's not what they are optimized for).
That said, something PV1 said got me wondering about how the system actually works. It does indeed have a damper that is actuated by the temperature selection. They thought it prudent to have the air flow bypass the heating coil when in the selector is in cool (down of the green dot). However in any mode the airflow still passes through the AC coil. So it's, filter first, then AC coil and then heating coil only if the selector is in heat mode.
With the heat on, one can use the AC to precondition the air before it gets heated. Mistu was pretty smart about how this whole system works. When making a selection all you are doing is telling the software what you want, or think you want. Then it decides what settings to actually implement to deliver the perceived desired result. I was able to find a couple of combinations that result in less than optimal adjustments by the software. But overall it is a very good and comprehensive system. Bottom line, if you simply can't get adequate results with defogging windows with the NON AC strategies, given previously by me and others, then just turn the dial to the defrost only mode. (Full right on the airflow selector) The system will turn on the AC in a limited way, for you.
Does it use more or less power to defrost with or without AC? That is a question that can only be answered for a specific set of conditions. Under most of them it will use more. There are also cases where it would use less. So do what works for you and get it off the full defrost setting as soon as conditions allow.
Canion fans can track all three usages, side by side, to see how things are working out AC/heater/summary(which of course includes all usage).
Interesting side note:
When you adjust the temperature controls in an ICE you adjust how much fresh cool outside air and how much is heated by the relatively stable temperature of the heater coil. Cooler settings more outside air less hot air and vice versa.
The 'i' controls the hot air temperature by controlling the water temperature (not by mixing hot and cold air). The very logistics of the system insures that an ICE will defog somewhat more easily than the 'i' will.