Vent Issue
Thread Starter
Instructor
Joined: Nov 2009
Posts: 242
Likes: 10
Vent Issue
I have a 69 non-A/C car that is having ventilation issues. When I set the controls on "Air" I assume I should have air coming from the vents in the lower dash? I instead have all the air coming out the defrost vents in at the windshield. I am assuming that I have a diverter door issue in the dash. I am guessing this is a vacuum problem, how much of the dash will I need to tear into to get to the vacuum controls?
Richard
Richard
Team Owner
Joined: Sep 2006
Posts: 31,315
Likes: 4,418
From: Westminster Maryland
Hi Richard,
The round vent in each of the lower dash pads are part of the 'Astro-Ventilation System'. They are opened by pulling **** that's to the side of each vent to open a little 'flapper' door that regulates the flow of outside air. Air flows out of the vent only when the car is moving
The left-side thumb wheel controls a small vacuum pot that opens and closes a door that sends the air driven by the blower motor to either the defroster vent or the heater floor defuser.
Where are you looking for air and under what conditions?
Regards,
Alan
This is the 'pot' that directs air flow to the defroster or floor vent.
The round vent in each of the lower dash pads are part of the 'Astro-Ventilation System'. They are opened by pulling **** that's to the side of each vent to open a little 'flapper' door that regulates the flow of outside air. Air flows out of the vent only when the car is moving
The left-side thumb wheel controls a small vacuum pot that opens and closes a door that sends the air driven by the blower motor to either the defroster vent or the heater floor defuser.
Where are you looking for air and under what conditions?
Regards,
Alan
This is the 'pot' that directs air flow to the defroster or floor vent.
Thread Starter
Instructor
Joined: Nov 2009
Posts: 242
Likes: 10
Hi Richard,
The round vent in each of the lower dash pads are part of the 'Astro-Ventilation System'. They are opened by pulling **** that's to the side of each vent to open a little 'flapper' door that regulates the flow of outside air. Air flows out of the vent only when the car is moving
The left-side thumb wheel controls a small vacuum pot that opens and closes a door that sends the air driven by the blower motor to either the defroster vent or the heater floor defuser.
Where are you looking for air and under what conditions?
Regards,
Alan
This is the 'pot' that directs air flow to the defroster or floor vent.
The round vent in each of the lower dash pads are part of the 'Astro-Ventilation System'. They are opened by pulling **** that's to the side of each vent to open a little 'flapper' door that regulates the flow of outside air. Air flows out of the vent only when the car is moving
The left-side thumb wheel controls a small vacuum pot that opens and closes a door that sends the air driven by the blower motor to either the defroster vent or the heater floor defuser.
Where are you looking for air and under what conditions?
Regards,
Alan
This is the 'pot' that directs air flow to the defroster or floor vent.
Team Owner
Joined: Sep 2006
Posts: 31,315
Likes: 4,418
From: Westminster Maryland
Hi S,
For 69 model year cars, without a/c:
In the AIR position the airflow is mainly directed to the floor outlets with a small amount of air directed to the defroster vent.
In the DE-FOG position the air flow is split between the floor outlets and the defroster vent.
In the DE-ICE position almost all air flow is directed to the defroster vent.
The RIGHT side thumb wheel is rotated to make the air flow hot or cold.
Regards,
Alan
This drawing illustrates how the Astro Ventilation System air flows and that it's not part of the car's heater/defroster system.
It's intent is to supply fresh air to the car without opening the windows.
For 69 model year cars, without a/c:
In the AIR position the airflow is mainly directed to the floor outlets with a small amount of air directed to the defroster vent.
In the DE-FOG position the air flow is split between the floor outlets and the defroster vent.
In the DE-ICE position almost all air flow is directed to the defroster vent.
The RIGHT side thumb wheel is rotated to make the air flow hot or cold.
Regards,
Alan
This drawing illustrates how the Astro Ventilation System air flows and that it's not part of the car's heater/defroster system.
It's intent is to supply fresh air to the car without opening the windows.
Last edited by Alan 71; Jun 15, 2017 at 09:57 AM.
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Interesting, when they removed the rear grilles front behind the window....did Astro Ventilation cease to exist? The air still is coming in from the vents,....but nowhere to go? Not that it matters to me much since I typically run with the T-tops off, or if not, the windows are down.
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Hi S,
For 69 model year cars, without a/c:
In the AIR position the airflow is mainly directed to the floor outlets with a small amount of air directed to the defroster vent.
In the DE-FOG position the air flow is split between the floor outlets and the defroster vent.
In the DE-ICE position almost all air flow is directed to the defroster vent.
The RIGHT side thumb wheel is rotated to make the air flow hot or cold.
Regards,
Alan
This drawing illustrates how the Astro Ventilation System air flows and that it's not part of the car's heater/defroster system.
It's intent is to supply fresh air to the car without opening the windows.
For 69 model year cars, without a/c:
In the AIR position the airflow is mainly directed to the floor outlets with a small amount of air directed to the defroster vent.
In the DE-FOG position the air flow is split between the floor outlets and the defroster vent.
In the DE-ICE position almost all air flow is directed to the defroster vent.
The RIGHT side thumb wheel is rotated to make the air flow hot or cold.
Regards,
Alan
This drawing illustrates how the Astro Ventilation System air flows and that it's not part of the car's heater/defroster system.
It's intent is to supply fresh air to the car without opening the windows.
Team Owner
Joined: Sep 2006
Posts: 31,315
Likes: 4,418
From: Westminster Maryland
Hi CC,
You're right.
When the right-side thumb wheel was moved to 'H' the thumb wheel also sent a vacuum signal to the small vacuum pot on the 'flapper mechanism' to close the doors so the air flow was stopped and the air in the interior would begin to warm.
Regards,
Alan
You're right.
When the right-side thumb wheel was moved to 'H' the thumb wheel also sent a vacuum signal to the small vacuum pot on the 'flapper mechanism' to close the doors so the air flow was stopped and the air in the interior would begin to warm.
Regards,
Alan
Thread Starter
Instructor
Joined: Nov 2009
Posts: 242
Likes: 10
Hi CC,
You're right.
When the right-side thumb wheel was moved to 'H' the thumb wheel also sent a vacuum signal to the small vacuum pot on the 'flapper mechanism' to close the doors so the air flow was stopped and the air in the interior would begin to warm.
Regards,
Alan
You're right.
When the right-side thumb wheel was moved to 'H' the thumb wheel also sent a vacuum signal to the small vacuum pot on the 'flapper mechanism' to close the doors so the air flow was stopped and the air in the interior would begin to warm.
Regards,
Alan
Is there a way to visually tell if the "flapper mechanism" is closing? Can you see it from the top vent area? Just curious what else on my car needs troubleshooting.
Rich
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