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a/c Stuck in defrost mode

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Old 01-27-2011, 08:50 AM
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a/c Stuck in defrost mode

Can someone explain to me how to fix my aircon as it will not blow from the front vents anymore - all it is blowing is hot air through the window defost mode, if possible can someone ford me a picture on where to locate the vacuum as i have been told to check the lines coming of it at that can cause this problem
 
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Old 01-27-2011, 09:39 AM
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The air distribution doors I think operate from vacuum solenoids under the dash. I would probly pull that lower cover off down near the transmission tunnel and see if, when you move the distribution switch, anything happens. If it doesnt, pull the vac line off and see if you're getting vacuum with the engine running. If you are, then it might be the switch itself. If not, trace that vac line to find the problem.
Dont know if you have the all electrical heater control panel or the one with three dials. The one with the three dials has vacuum lines running into the back of it that you should probly take a look at.
 
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Old 01-27-2011, 09:44 AM
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Heres a pretty good thread about this issue i think. It says that the default setting is defrost only if you lose vacuum. maybe it will help you find your problem.
https://www.ford-trucks.com/forums/8...e-defrost.html
 
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Old 01-27-2011, 10:15 AM
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Check behind your battery box for a broken or kinked vacuum line running through the firewall of your vehicle from the vacuum reservoir. Defrost is indeed the default position when vacuum is lost. Behind the battery box is usually the culprit.
 
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Old 01-27-2011, 01:19 PM
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See FAQs in HVAC forum.
 
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Old 01-28-2011, 06:49 AM
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Thanks for your feedback
we found the problem today. One of the vacuum lines on a spliter was damaged (like it had been burnt) replace the damaged line and all now works fine.I think it is working alot better then before. The cab seem to get cooler alot quicker
Once again thank for you feedback
 
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Old 01-28-2011, 07:28 AM
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Glad you fixed it!
Was is the splitter behind the battery, like near the firewall? Or that one that sits nearer to the engine
 
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Old 01-28-2011, 07:36 AM
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it was located the firewall
 
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