Heating/AC Question

that's great to know, i'll have to try again, thanks ron!

if i change fan speed, what happens when it reaches desired temp?

 

Ok, I played with the available Techstream settings some more. There doesn't seem to be one that totally stops it playing with the outlets. There's one called something like "FOOT/DEF control" that is normally ON, and the help text says something in broken English like "control whether outlet from FOOT/DEF when turn AUTO on" (not verbatim, but close). I tried both settings and didn't see anything happen differently.

There's also a "FOOT/DEF Blow Up" setting, on/off, something to do with whether switching to FOOT/DEF increases the fan speed. I tried both settings, my fan speeds up either way. Again I couldn't see it make any difference.

There is definitely a setting for that, and it does what it says. It's called "air inlet control", and if you set it OFF, then auto mode doesn't futz with your fresh/rec*culate settings.

So altogether, not a super productive evening with the Techstream settings, but at least I did finally turn off the infernal beeps for every keyless lock/unlock. I was afraid the neighbors were going to set up a beep jar and I'd have to drop quarters in.

Yeah, I'm not even sure how to test this behavior. I do remember, from more temperate spring weather, the system would come on in foot/face and then as the cabin got more comfortable, switch to full face. I could wait for cool weather again, then watch whether it still does that if I have 'canceled' auto by changing the fan speed.

-Chap

 

Nothing, I think, as long as you didn't press AUTO after changing the speed.

It's a tricky HVAC system. Some of its automated tricks are helpful, some are confusing (as illustrated by this thread), and some obnoxious.

 

I am going to expand on this question. Setting (In Auto Mode) with ONLY the fan being over rode. I believe that is what bisco is implying. Remember Auto Mode will still work on parts of the system that have not been manually adjusted (over rode).

Actually, a little more than nothing IMO. A lot of what happens is controlled by other factors besides the "reaching the desired temp". Once that happens other factors are involved such as the ambient temperature (outside), humidity, and time of day or night. During the winter the system might actually kick on the a/c compressor and one might feel air coming out of the vent's on the dash rather than the foot area. During the summer, usually the a/c compressor will wind all the down or even cycle on and off. As stated previously, it is a complicated system that has a lot of different controls. I have also observed that at night time the recirc might change over to fresh air even when it is in auto mode with the a/c running.

The easiest way to answer your question of what happens when it reaches desired temp? It then simply takes necessary steps to automatically maintain said desired temp whether that could involve using a/c or heat. There really is no pat answer as there are too many variables involved.

 

OK, when I said "nothing," I meant nothing normally happens automatically as a result of reaching the set temperature, except that the system obviously will back off the heat or cooling as needed. (That's the long version.)

If Bisco hadn't changed the fan speed (as specified in his original question), the fan typically would slow upon reaching (or nearing) the set temperature. In my car, with both AUTO and ECO options selected, on warm days the fan starts at a higher speed (How high depends on the difference between interior and set temperature.), then works its way down to its second-slowest speed---never the lowest, so far. That doesn't take long, either.