Footwell Heat / Hot Sill Again
#17
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Not sure if you've seen this older thread on the subject that has more information about the rear flappers:
https://rennlist.com/forums/964-foru...lap-boxes.html
See especially posts 14, 15 and 21
https://rennlist.com/forums/964-foru...lap-boxes.html
See especially posts 14, 15 and 21
#18
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Great thread, thanks. As my Indy explained it, if all is well with the heater servo motors the heat either dumps out the flapper valves to under the car (heat off) or due to what they call "differential pressure" (heat on) the flapper valve stays closed and hot air continues up the rockers (inside a tube) to the footwells up the PITA hose to the HVAC distribution box under the hood.
Both flapper valves seemed to be operating fine. I’m guessing there’s an issue with the heater servo motors and there’s no “differential pressure”. Blazing hot in the car when this goes bad.
Both flapper valves seemed to be operating fine. I’m guessing there’s an issue with the heater servo motors and there’s no “differential pressure”. Blazing hot in the car when this goes bad.
#19
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#22
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When it gets colder next month I will pull a pair out of the basement and see if it corrects the problem. Thanks for the diagnosis Jason!
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#23
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I still don't fully understand how these vents can affect the HVAC. I thought to understand that the HVAC system is essentially a closed system from back to front and due to it being a closed system it is possible to cause the differential pressure change, causing the exhaust flapper boxes to operate and so on.
I thought these internal vents were just there to stop it being so difficult to close the door when the windows are closed. I presumed that the older Beetles did not have this type of vent and it is therefore so difficult to slam the old Beetle doors
I thought these internal vents were just there to stop it being so difficult to close the door when the windows are closed. I presumed that the older Beetles did not have this type of vent and it is therefore so difficult to slam the old Beetle doors
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#24
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I'm unsure as well. I removed mine when I put the rs carpet in. I have no problems at all. Although they are covered in the carpet. I know you guys have way more knowledge than me but i thought they were to help when closing the doors too?
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The other thing I read here was they have a tendency to melt if there is a problem with the 'flow' of the HVAC system. I mean the plastic of the insert in the picture by JasonAndreas melts.
What exactly is at the bottom / outside of this vent? Is the exhaust right there? I guess my question is, where does the vent vent to?
What exactly is at the bottom / outside of this vent? Is the exhaust right there? I guess my question is, where does the vent vent to?
#26
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Originally Posted by FoxMan
I suddenly noticed that that heat is pouring into the car from the rear. The left driver side door sill was cooking, and so was I. And there’s heat pouring through the right side by the vent under the rear side window. Not a fun ride home.
Originally Posted by Dingo
Although they are covered in the carpet.
Originally Posted by MakSiNG
I guess my question is, where does the vent vent to?
#27
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The rear flap vents are for letting air out of the cabin. All cars have such vents.
The rubber flaps open when sufficient air pressure is made in the cabin by either the two main blowers or the fresh air intake under the windscreen.
An open or missing rear vent will not affect HVAC operation at all, unless there's an air leak from the heat hose in the vicinity that forces heated air in through these openings.
Cheers,
Tore
The rubber flaps open when sufficient air pressure is made in the cabin by either the two main blowers or the fresh air intake under the windscreen.
An open or missing rear vent will not affect HVAC operation at all, unless there's an air leak from the heat hose in the vicinity that forces heated air in through these openings.
Cheers,
Tore
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Quick update.
Number 3) above.
I decided to take another look at the cardboard hose in the passenger footwell because it is in bad shape and I wanted to make sure since this seems to be the only ? in the system. Well upon reinstalling it (second time now) it did indeed rip a hole in it![grr](https://rennlist.com/forums/graemlins/cussing.gif)
So now I definitely have a problem. It sorted the dilemma of to change or not to change though. So I will be replacing this and report back for, hopefully, sake of closure.
One question for the expert though:
Am I buying the left or the right hose? From which perspective is this? From the front of the car looking towards the back or from the perspective of the driver?
Many thanks!
Number 3) above.
I decided to take another look at the cardboard hose in the passenger footwell because it is in bad shape and I wanted to make sure since this seems to be the only ? in the system. Well upon reinstalling it (second time now) it did indeed rip a hole in it
![grr](https://rennlist.com/forums/graemlins/cussing.gif)
So now I definitely have a problem. It sorted the dilemma of to change or not to change though. So I will be replacing this and report back for, hopefully, sake of closure.
One question for the expert though:
Am I buying the left or the right hose? From which perspective is this? From the front of the car looking towards the back or from the perspective of the driver?
Many thanks!
#30
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