My 06 F250 crew with the 6.0 starting blowing the cold AC out the defrost vent and will not switch to the dash vents. It's goning to hit 108 today and stay around 105 for the rest of the week. Can someone step me thru some troubleshooting.
thanks, Jim

 

The FAQs above will get you started.

 

Thanks for the answer, but when I go to the FAQ section it states that I need 25 post to use the FAQ search. Am I just missing something or is it off limits to those who don't use the site very often? Sorry to be a pest, but I really want to start tracking down the ac problem. thanks again, Jim

 

There is a door in the blower box that is not moving.
It can be either electrically or vacuum controlled.
At times the hinge will break.

 

The second post in this section says:

Read First: HVAC FAQs for 97-03 F-Series (including Navigator & Expedition)

When something says Read First: , you are supposed to READ IT FIRST.


You are thinking of the temperature blend door which is not the issue.

 

You are incorrect.
The door I am talking of directs airflow to the defrost and floor vents.When the hinge breaks air is directed to defrost.

 

Perhaps. Never seen one of those break compared to all the broken blend doors.

Since the airflow also defaults to defrost when vacuum is lost and that is an extraordinarily common failure, it pays more often to go with the odds in the absence of any data to the contrary.
.

 

Look under the dash. The switch where you select the mode works by means of small vacuum tubes attached to it. You either seem to have a leak, or a hose is simply disconnected, leaving the AC on a single (frozen) defrost vent position, because it is unable to do anything else.

 

Thanks everyone for the help.
Here is what I found, please excuse my lack of technical names. I pulled the line that looks like it was heading thru the firewall and found little or no vacumn. The same is true for the line attached to some kind of diaphram on what looks like a water line.
Traced those back to a cannister like device being fed by a pump on the firewall. Pump seemed to be running and has some vacumn if you disconnect the lines.( not sure how much vacummn is normal)
Cannister feeds another device on the firewall (small plastic looking thing with a white top and two lines attached) I removed those two lines and plugged them. AC vents starting working.
What is that device and what does it do ? It looks like one of the lines heads down along the engine and disappears. To where ?? I assume the other line is feeding vacumn to the device.

thanks, Jim

 

A door problem..
I've seen it oodles of times.
Glad you got it repaired.

 

Speaking of reading comprehension.
His truck is a 96.
The HVAC facts state 97.
Hmmmmmmm

 

He has an 06, not a 96. Talk about misplaced concern in complaining about "reading comprehension"....

Before directing him to the posted FAQs, I first verified that the 06 utilized the same control system as the previous version. If it had been a different system, different advice would have been given.

Look, we both have extensive experience and knowledge of these systems that may be of use to the general membership. I suggest stopping your attempt to get a pissing contest going and instead to focus on assisting the "average Joe".

 

Haha, his is an 06, you sent him to 03.
So you do read.


You could attempt to give sound advice rather than chiding someone with a know it all attitude.

You know very well people do not read information.

No pissing match.

 

OK.
I do appreciate that a lot of good people share their knowledge for free to complete strangers.
In my last post , I was hoping to find out about some components. What they are, where they go and what they do. Especially the plastic component on the fenderwall that has a line coming from the cannister and one going down alongside the engine. How do I determine that it is working properly ? Where does the line go ? How strong should the vacumn feel ? thanks again, Jim

 

Can someone tell me what the component is that is mounted to the inner fenderwell driectly behind the passenger side battery. It has 3 electrical wires ( in one connection) and 2 vacumn lines attached to it. Where does the vacumn line go ? thanks, Jim