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Old 07-10-2020, 10:02 PM   #1
GA Cowboy
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Opening under dash

Can anyone tell me what this opening under the control box? under the dash is? The AC is blowing out about 60 degrees but 40 on this vent. Thanks.
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Old 07-10-2020, 10:14 PM   #2
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Question Re: Opening under dash

I've always wondered what it was for also. I always figured it was for your feet. I would like to know the reason for it also.
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Old 07-11-2020, 12:02 AM   #3
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Re: Opening under dash

If it is blowing that cold I would venture to say its there to prevent the unit from freezing up.

Common sense, SWAG, or corrected error on part of GM.
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Old 07-11-2020, 12:07 AM   #4
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Re: Opening under dash

I always figured it is for the feet if desired. You should be able to shut it.
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Old 07-11-2020, 07:04 AM   #5
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Re: Opening under dash

The only way mine would blow 40 degrees would be in the dead of winter before the engine wanted delete here.

I think it's more of a winter time heat option to help warm or dry wet feet. It pops shut with a little pressure.
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Old 07-11-2020, 08:41 AM   #6
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Re: Opening under dash

It's just an additional vent and clearly you are getting heat polution in your duct system from somewhere else. If it is blowing 40 out of there then that is the temp your ac is cooling to. You need to check flapper doors, heater shut off valve, etc. and you should be able to get 40 degree air from all the vents.
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