5v/cyl

When your AC is on if the firewall lines are cold then the condenser is cold in the airbox. A abstruction to the air flowing through to be cooled is the only reason it wouldn't work. Blend door.

jseklund

The blend door makes sense. My other thoughts, and I'm no HVAC expert -

Are you sure your blower motor works? Maybe the fan isn't blowing the air?

What about a clogged evaporator or orifice valve? Not sure about these, and I doubt it, but maybe???

t_andrews

Glad to find this thread and many thanks for posting a blend door photo.

Whilst troubleshooting my issue I had gone thru the coolant bleed step, and pulled the cabin air filter looking for mice doing pushups with my cabin input door. I did notice the input door under the filter was very slow to move, but VAG hvac errors didn't suggest it was the problem.

VAG did suggest it was the central blend flap, but I was unable to determine how to check that visually. If the steps to pull the glove box are simple, would someone post them? Kick panels, then glove box? I had the a4 ebahn manual until I went to win7 :-(

I did notice there was a foam pad under the cabin air filter that no longer seemed completely intact, perhaps parts of it found their way to the central flap and bound it up...

Can anyone speak to an in car repair or permanent (for winter) hot air workaround? Wired central blend door dealio?

Hvac diagnostics suggested my central flap measurement was "out of range" which suggests to me the actuator arm has left the armature. Running the hvac diagnostics is a good suggestion as a bit of hvac yoga to loosen heater flap joints, but sadly left me cold ;-)