You almost answered your own question. As the heated air passes through the AC evaporater the moisture gets stripped off by the cold fins. (much the same reason your window fogs!) It drips out the bottom of the truck instead of blowing back on the windshield. If you have access to an ACed vehicle that you can disengage the ac when on defrost then experiment. Crank on the defrost without the AC on. As soon as the window starts thawing the rest of the windows condense because of the cold window and warm moist air....now hit the ac.....fog will disappear in seconds!
What the fog!!!!!!
- Thread starter acon40
- Start date
You almost answered your own question. As the heated air passes through the AC evaporater the moisture gets stripped off by the cold fins. (much the same reason your window fogs!) It drips out the bottom of the truck instead of blowing back on the windshield. If you have access to an ACed vehicle that you can disengage the ac when on defrost then experiment. Crank on the defrost without the AC on. As soon as the window starts thawing the rest of the windows condense because of the cold window and warm moist air....now hit the ac.....fog will disappear in seconds!
Well that's why I'm confused...my red truck has A/C and I've had it blowing "defrost" (maybe I'm getting confused by the terminology - or maybe newer vehicles have more sophisticated systems) - had the lever on the little defrost symbol - which focuses all the hot air onto the windshield - every morning lately, with no fogging. But maybe the A/C will enhance the drying effect...I'll check it out tomorrow.
60wag
Rising Sun Member
- Joined
- Aug 23, 2005
- Messages
- 2,479
Umm.... close but not quite. Heating the air increases the capacity of the air to hold moisture - The RH goes down if the amount of moisture is held constant. By chilling the air across the evaporator coil in the AC, the RH exceeds 100% and water condenses out. So the moisture content is no longer constant. Once the air is then heated by the heater core, the RH is lower than is it had never passed by the evap coil.
As for inside vs outside air...... usually the outside RH is lower than the inside RH so I'd leave the recirc off, if you can.
edit: oops, I guess I should have read page 2 first.
As for inside vs outside air...... usually the outside RH is lower than the inside RH so I'd leave the recirc off, if you can.
edit: oops, I guess I should have read page 2 first.
acon40
Banned
man do i start some threads. My ac does NOT come on in the 95 cruiser. My question is can i swap out my setup for a auto climate setup. I tend to battle the setting nonstop and i am sick of it.
On a side not i have used the rain x fog solution and it worked GREAT on my last truck so i will try it and report back.
On a side not i have used the rain x fog solution and it worked GREAT on my last truck so i will try it and report back.
SteveH
Hard Core 4+
Leave some windows open a few inches in your garage, or outside on a sunny day. This will dry out any accumulated moisture. Remove the floormats and let the moisture under them dry out, as well. This works well in Colo. where the humidity is so low - not so well in wetter areas. I never use recirc., as it fogs up the inside fairly quickly.
Rezarf
Hard Core 4+
Confirmed on my trip in this morning that when I hit the defrost button (full defrost, not the defrost/floor mix button) my AC comes on and the HVAC systems switches to "fresh air" mode. FWIW
As to your question about the auto climate setup...Here is a MUD thread on this very thing and the answer is, I believe, yes but it is probably more work & $$ than it is worth --> Auto Climate Control MUD Thread
The manual to auto swap is lower down in the thread.
That said, I'm not sure the behavior of the defrost/AC/fresh air has anything to do with the auto climate control or not
- Honestly I never even use the auto climate control feature in the LX - although sliding the temp selector will give you way more fan speed settings in auto mod than the 4 (IIRC) you have today...Kind of like an adjustable ceiling light slider deal that will brighten and dim lights. Anyway, when I did my test this morning I didn't have my HVAC controls in auto mode. Not sure how it behaves in auto mode?I can tell you if you from experience though if you don't have the "temp sensor" plugged into the HVAC unit you only have two choices for temperature...Full hot or full cold. If this is the same sensor that the MUD thread mentions (didn't read it all the through) as needing for the manual to auto swap then...well lets just say it won't work well without it
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acon40
Banned
You know what. I am over it. I will just buy the anti fog stuff hahaha $4 well spent.
Noted mine today is the same as you describe. Defrost button selected, AC comes on and outside air door opens......
Off of original topic but when I got my 40th the CC was less than good! After fiddling with it I discovered the hose floating behind the dash....which I put back on the sensor bung. It worked much better but still was not even close to the temp ranges so I replaced the thermistor with a new one from Toy. That did the trick and my CC works very well! Sprayed the evaporator with a can of Frigi-fresh Robbie gave me this summer and it was spooky haw much black muck ran out of the drain tube! I will definitely do that to a higher degree next spring!Soooooo....back to the topic at hand....Acon, have you had any solutions yet from this banter?
Smart band-aid!