Question about 2000 Chevrolet Blazer

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Will not blow heat to floor

Controls work to direct heat anywhere else. Vacuum control is working under dash. I can see it turning the arm that is supposed to blow heat to the floor, but it looks really loose where is goes through the housing. How do I tell if the door is broken, and how do I fix it if it is?

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  • 3 Answers

Check that hose which directs heat to floor has not become loose

Posted on Jan 06, 2013

  • Dennis Hommerson Jan 06, 2013

    There is vacuum pressure that is turning the arm to the door. I can see it move s I cycle thru the modes. But the white plastic arm that goes thru the housing to the door itself looks really loose and I don't think it's actually moving the door. How do I replace that door is probably the better question?

  • Dennis Hommerson Jan 06, 2013

    Ok, just did some more investigating... When I switch it to floor, it leaks a little to the floor, but mostly blows to defrost. Any thoughts on that?



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Posted on Jan 02, 2017

  • 15 Answers

SOURCE: heater controls do not work

have you tried flushing out your heater core? i thought mine was that also but i flushed out my heater core with a water hose and it is hotter than when i bought the truck

Posted on Jan 02, 2010

  • 1114 Answers

SOURCE: 95 baretta, after heater core replacement

Check the fan relay.

Posted on Feb 03, 2009

  • 1959 Answers

SOURCE: Vacuum leak to AC controls 2000 Chevy Lumina

Check the vacuum lines, starting at the firewall in front of the passenger side and trace backward.

Posted on Jun 19, 2009

  • 38 Answers

SOURCE: air only blows out the floor and defrost duct work

check for vacum leak under hood sould be small plastic hose good luck

Posted on Jun 24, 2009

  • 14 Answers

SOURCE: AC blowing behind dash

on your vehilce it does not use vacuum to control the vent direction.
It uses a series of actuators (electrical).
My guess is that the air blows out the defrost (top vents) this is the default position for the mode door actuator.
More than likely it will have to be replaced.

Posted on Aug 07, 2009

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