Heater/AC controls-HELP!!
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Pro
Joined: Mar 2006
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From: Spring Hill Florida
Heater/AC controls-HELP!!
Has anybody taken apart the '86 manual controls for the heater/AC control unit that is in the dash? The manual shows many vacuum hoses going to various "pots" and some of mine don't work right. I have no heat and the AC is weak. The "flap" for the defroster is in the defrost mode and all the AC goes out that vent. Before I tear this apart, does anyone have any suggestions?
Melting Slicks
Joined: May 2014
Posts: 2,891
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From: New Port Richey FL
Has anybody taken apart the '86 manual controls for the heater/AC control unit that is in the dash? The manual shows many vacuum hoses going to various "pots" and some of mine don't work right. I have no heat and the AC is weak. The "flap" for the defroster is in the defrost mode and all the AC goes out that vent. Before I tear this apart, does anyone have any suggestions?
So when you move the Vent Selector can you hear a Vacuum hiss as you move from Vent to Vent if so that would show you have Vacuum to the System. Then you could go to some of the vents and see if the request is getting to the vent you are looking at, I have seen the Rotary Valves be clogged but it is Rare.
If you hear a constant Vacuum Hiss you have a leak inside the Dash. If you hear Nothing check for a Broken Vac. tube or Hose under hood. (no supply No vent movement) Your concern that all venting goes to the Defrost That is a Default position it is Thought to see better (defrost/clear windshield) than be 100% comfortable
Last edited by s carter; Dec 11, 2017 at 09:39 AM.
Thread Starter
Pro
Joined: Mar 2006
Posts: 700
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From: Spring Hill Florida
Before you start pulling things apart you need to confirm you have Vacuum to the Control because the problem may be under the hood.
So when you move the Vent Selector can you hear a Vacuum hiss as you move from Vent to Vent if so that would show you have Vacuum to the System. Then you could go to some of the vents and see if the request is getting to the vent you are looking at, I have seen the Rotary Valves be clogged but it is Rare.
If you hear a constant Vacuum Hiss you have a leak inside the Dash. If you hear Nothing check for a Broken Vac. tube or Hose under hood. (no supply No vent movement) Your concern that all venting goes to the Defrost That is a Default position it is Thought to see better (defrost/clear windshield) than be 100% comfortable
So when you move the Vent Selector can you hear a Vacuum hiss as you move from Vent to Vent if so that would show you have Vacuum to the System. Then you could go to some of the vents and see if the request is getting to the vent you are looking at, I have seen the Rotary Valves be clogged but it is Rare.
If you hear a constant Vacuum Hiss you have a leak inside the Dash. If you hear Nothing check for a Broken Vac. tube or Hose under hood. (no supply No vent movement) Your concern that all venting goes to the Defrost That is a Default position it is Thought to see better (defrost/clear windshield) than be 100% comfortable
Team Owner
Joined: Sep 2003
Posts: 25,383
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There's a vacuum select switch on the C60 control. There's also I believe a vacuum control for HEAT. The FSM documents operation quite well I believe. Do you have the FSM?
#2 is Vacuum Select and #11 Heat Select
#2 is Vacuum Select and #11 Heat Select
Melting Slicks
Joined: May 2014
Posts: 2,891
Likes: 591
From: New Port Richey FL
OK it sounds that you have Supply to the Valve, if you take the Control out leaving the controller in car connected, you can take the Vac. Supply off the Rotary Valve and make yourself a jumper from the Multi hose connector out of a piece of Washer hose and a couple of Hose Splice's. with that in place you can go Port to Port feeling for Vac. in each port of the Rotary valve, you can also go to the different Blend doors and see if you have function of them too.
Thread Starter
Pro
Joined: Mar 2006
Posts: 700
Likes: 2
From: Spring Hill Florida
There's a vacuum select switch on the C60 control. There's also I believe a vacuum control for HEAT. The FSM documents operation quite well I believe. Do you have the FSM?
#2 is Vacuum Select and #11 Heat Select
Attachment 48234217
#2 is Vacuum Select and #11 Heat Select
Attachment 48234217
