Question AC Mixer Trouble

[jsa75]

A few months ago I was having a problem with my AC/Heat where when I turned the Hot/Cold mixing knob the setting would not change. It would get stuck on heat and I would have to play with the controls for a while to get it to switch to AC.

Finally, it is now completely stuck on HEAT and being that I live in Florida and it is June... I need a solution fast. Does anyone have experience with this issue? I think that the AC system itself would work, but I think that something has gone out. Any ideas?

 

[bushpilot]

what model year are you talking about.

there is a heater control valve under
the HOOD that sounds like its stuck... the valve
is on the passenger side (above the valve cover)
and typically is in-line of the heater hose that
feeds to the heater core in the firewall.

the valve looks like the ones in these
links http://www.dieselsite.com/index.asp?PageAction=VIEWCATS&Category=578

 

[jsa75]

2002 7.3 Liter F250

What is the look?

 

[JLDickmon]

2002 7.3 Liter F250

What is the look?

he meant "under the hood, and it looks like these"

He gets like that when he's on his laptop in an un-named airport in some God-forsaken BFE town...

You can check it, but I personally doubt that's the problem..
drop the glovebox so you can look at all three door actuators. (two back there, one in the driver's footwell above the trans hump)
make sure they're swinging when you change it from defrost to heat to ac..
recirc to fresh
and hot to cold

the door motors like to croak, and I've replaced a couple of heater boxes because the doors themselves broke...

 

[bushpilot]

he meant "under the hood, and it looks like these"

He gets like that when he's on his laptop in an un-named airport in some God-forsaken BFE town......

Thanks for covering for me JL