Never really did have a good understanding of this, most vehicles I have owned have the capability to allow for outside air without actually having the fan on?

Anyway, the A/C works OK but here's what's weird. It seems to me, that the only time the A/C (compressor) should be operational is when the selector is in one of the two positions - A/C or Max A/C right? But there is noticeably cold, dry air from the vents when the selector is placed in any of the postions to the right side, so long as the other selector is fully counterclockwise. I can tell, because on hot, humid Iowa July days, there ain't no cold air around. So it's not a bad thing necessarily, but is something broken or not working right?

 

To my knowledge, the compressor clutch may/will be enabled in the defrost or defrost/mix mode settings. This is to allow dehumidified air to clear the windshield. The air can be warm or cold, but it will be dehumidified unless you install a switch to disable the clutch in those positions.
Try checking the 'floor' and 'panel' only position and I bet you'll find the air to be ambient temperature.
tom

 

Aha! Will have to delve into the owners manual (again)

 

Ford doesn't make it obvious. The A/C runs in all positions except for Dash only, Floor only, or Off. The fan runs in all positions except for Off.

 

I get the impression, the fan must be on to get fresh outside air flowing through the cabin?

 

Yup. You can hear the vacuum control closing the vents when you choose OFF.

I can't say that I like the way it operates. I still prefer the way the old vehicles vents operate. I remember that they would have a 4" hose snaking from the grill area to the vehicle interior. At a 70 mph road speed, you'd have a 70 mph breeze blowing thru the vents. You only needed a fan when you're stopped. Sometimes a breeze is better than A/C.

 

Yeah that doesn't really seem like the best design. At least I understand what's what, thanks for the info everybody.

 

GM started the 'fan always on' theme back in the 1970's, and found they had a bunch of warranty claims for worn out blower motors. Ha. Replacement of the blower motor for a 69 Buick Special required removal of the right front fender. Drilling a hole and adding lube was quicker & easier. RTV to seal.
You could not turn the fan off, as I recall, no matter the HVAC control position selected. Now I am wondering if indeed it did run in the HVAC control OFF position. There was no OFF for the blower speed selection. Been too long.

tom

 

Well that's just it. In my old truck heater works great provides fresh air even with the fan off and air flow continues over the heater core if desired.