ac blower won't change from the window defroster to the dash vents
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ac blower won't change from the window defroster to the dash vents
I have a 87 trans am and I installed a ac blower and it blows perfect for the defroster on the windshield but won't work on the dash vents that blow towards you!! When I was installing the blower I notices that it had two hard lines in the engine bay on the firewall, I didn't hook those up because I didn't know where to hook it up. Can that cause the problem? I think it's two vacuum lines that's on the fire wall but I don't know where to connect them. Please help!!
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Re: ac blower won't change from the window defroster to the dash vents
It has two lines coming from passenger side firewall and it looks like wires but there not I think there vacuum lines that control the ac doors. Do you guys know where too hook them up?
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Re: ac blower won't change from the window defroster to the dash vents
vacuum hose from the hard line to the heater control valve and from the manifold to the hard line going to the heater controls.
without them, you wont be able to switch from defrost to vents; you need vacuum
without them, you wont be able to switch from defrost to vents; you need vacuum
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Re: ac blower won't change from the window defroster to the dash vents
And where can I buy the heater control valve?
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Re: ac blower won't change from the window defroster to the dash vents
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Re: ac blower won't change from the window defroster to the dash vents
You can buy the valve from Advance/AutoZone/or any parts store relatively cheap;around 20 bucks, I recently bought one.
The one line comes from a tee from the plenum and vacuum caniser(ball in the drivers fender by the battery)to a small check valve to the hard line in that harness by the pass firewall. The other runs from the hardline on firewall harness to Heater Control Valve as shown in the photo I attached earlier.
The one line comes from a tee from the plenum and vacuum caniser(ball in the drivers fender by the battery)to a small check valve to the hard line in that harness by the pass firewall. The other runs from the hardline on firewall harness to Heater Control Valve as shown in the photo I attached earlier.
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Re: ac blower won't change from the window defroster to the dash vents
You can buy the valve from Advance/AutoZone/or any parts store relatively cheap;around 20 bucks, I recently bought one.
The one line comes from a tee from the plenum and vacuum caniser(ball in the drivers fender by the battery)to a small check valve to the hard line in that harness by the pass firewall. The other runs from the hardline on firewall harness to Heater Control Valve as shown in the photo I attached earlier.
The one line comes from a tee from the plenum and vacuum caniser(ball in the drivers fender by the battery)to a small check valve to the hard line in that harness by the pass firewall. The other runs from the hardline on firewall harness to Heater Control Valve as shown in the photo I attached earlier.
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Re: ac blower won't change from the window defroster to the dash vents
IROCgiraffe, this is either gonna get bad, worse, or repaired. He didn't mention that his HVAC was GONE when he bought it! So, on that note, back to square one.
I'll look for a diagram of a complete hose/routing combo thingie and see what we can do. Mercy!
I'll look for a diagram of a complete hose/routing combo thingie and see what we can do. Mercy!
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Re: ac blower won't change from the window defroster to the dash vents
OK, Start with this.
Attachment 280370
You will need to go to the store and get the hoses, Heater diverter valve, and clamps to get the system "back to original".
Then we'll work on the vacuum line/lines to control it.
Attachment 280370
You will need to go to the store and get the hoses, Heater diverter valve, and clamps to get the system "back to original".
Then we'll work on the vacuum line/lines to control it.
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Re: ac blower won't change from the window defroster to the dash vents
My car didn't have a/c or heat nothing when I bought it. I went and bought a blower and blower box put it in got a heater core and ran hoses from the intake manifold and back. It works great but just blows threw the defroster vent. What's the heater control valve? I'm so confused
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Re: ac blower won't change from the window defroster to the dash vents
no mine I hear a hissing from the climate control panel when it is on, so I know it's a vaccuum leak that is not allowing the flap to divert the air from the blower to where I want it.... my heater core is currently bypassed due to it leaking, but my vaccuum line to the heater valve is still attached, so I doubt it's the heater valve under the hood since it control coolant flow, not the air direction.
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Re: ac blower won't change from the window defroster to the dash vents
no mine I hear a hissing from the climate control panel when it is on, so I know it's a vaccuum leak that is not allowing the flap to divert the air from the blower to where I want it.... my heater core is currently bypassed due to it leaking, but my vaccuum line to the heater valve is still attached, so I doubt it's the heater valve under the hood since it control coolant flow, not the air direction.
Last edited by Bob88GTA; 07-17-2014 at 12:47 PM. Reason: more info
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Re: ac blower won't change from the window defroster to the dash vents
Correct IROCgiraffe; 2 hard lines..........1 straight to the heater bypass control valve for LIQUID FLOW, and 1 line from vacuum source from plenum/vacuum ball to operate the heater "FLAPS in the dash. Like I said, "back to original". He don't NEED it, but he needs the OTHER line to operate the FLAPS for the vent
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Re: ac blower won't change from the window defroster to the dash vents
Correct IROCgiraffe; 2 hard lines..........1 straight to the heater bypass control valve for LIQUID FLOW, and 1 line from vacuum source from plenum/vacuum ball to operate the heater "FLAPS in the dash. Like I said, "back to original". He don't NEED it, but he needs the OTHER line to operate the FLAPS for the vent
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Re: ac blower won't change from the window defroster to the dash vents
You could have a helper pull on the lines under the hood in the harness while you feel for them moving at the controls.
hook up one from the rear of the plenum straight to one or the other hard lines one at a time, start car and select VENTS. If it doesn't shift from defrost, try the other hard line, it SHOULD WORK, unless that plastic rubber hose connection behind your controls is messed up and leaking. If its leaking, you will here it hissing like IROCgiraffe mentioned. A little dab of silicon will fix that
Once figured out, you will still need a "T" to go to the plenum and over to the vacuum ball.
I wanted to know where you were cuz we'll celebrate when YOU fix it. Of course, thats gonna be a long drive for me!
PS:SEE RED EDIT
Last edited by Bob88GTA; 07-17-2014 at 03:21 PM. Reason: more info
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Re: ac blower won't change from the window defroster to the dash vents
Lmaooo ... Where you at!!? I would love too meet up with the master ac tech!
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Re: ac blower won't change from the window defroster to the dash vents
haha, Huntsville Alabama, 930 miles south of you! Master ac tech........NOT!
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