a/c problems
ebrigham08
12-22-2008, 09:59 PM
when i turn on the a/c in front it doesnt blow through the vents just through the vent by the windshield and when i turn on the a/c in back it only blows hot air. whats the problem?
tripletdaddy
12-23-2008, 12:06 AM
Welcome to the Auto Forum. It would help us out, if you would provide us your year, engine size/type, manual or electronic climate controls, and other unique, relevant features your vehicle may have. Sometimes mileage, depending on the problem and any related, previous work would be informative as well.
Off the cuff, your air only going to the defrost vents sounds like you may have a vacuum supply or vacuum line problem, probably a line disconnected. The default position for the hvac system always goes to the defrost position when there is no vacuum. Do you hear any hissing or sucking sounds inside under the dash or under the hood? Have you noticed any performance issues or the check engine light? Under the glove box area, you should see different colored small tubes that connect to at least one metal can like things. There are three of these vacuum controllers under the dash in the front (I believe) and one in the back. They control the position of the vent direction for the defrost and the heat and the ac recirculation air inside the hvac box and. The problem up front may also have to do with a vacuum tee/check valve that goes to a vacuum reservoir found under the right(pass) side cowl. They are known to cause problems/break.
The problem in the back may be vacuum related as well, assuming they began at the same time. If you try to operate the ac in the back, do both front and back controls only give you heat? I believe the temperature is vacuum controlled by moving a cold/hot air blend door.
If it is not warm enough out, the ac system won't even come on. It needs to be at least 45 to 50 deg F for it to come on to prevent it from freezing up. Is it warm enough for you to need the ac on? Will it even come on?
Off the cuff, your air only going to the defrost vents sounds like you may have a vacuum supply or vacuum line problem, probably a line disconnected. The default position for the hvac system always goes to the defrost position when there is no vacuum. Do you hear any hissing or sucking sounds inside under the dash or under the hood? Have you noticed any performance issues or the check engine light? Under the glove box area, you should see different colored small tubes that connect to at least one metal can like things. There are three of these vacuum controllers under the dash in the front (I believe) and one in the back. They control the position of the vent direction for the defrost and the heat and the ac recirculation air inside the hvac box and. The problem up front may also have to do with a vacuum tee/check valve that goes to a vacuum reservoir found under the right(pass) side cowl. They are known to cause problems/break.
The problem in the back may be vacuum related as well, assuming they began at the same time. If you try to operate the ac in the back, do both front and back controls only give you heat? I believe the temperature is vacuum controlled by moving a cold/hot air blend door.
If it is not warm enough out, the ac system won't even come on. It needs to be at least 45 to 50 deg F for it to come on to prevent it from freezing up. Is it warm enough for you to need the ac on? Will it even come on?
tripletdaddy
12-23-2008, 12:21 AM
I forgot to mention that Autozone.com is a good reference for diagrams and repair instructions. You'll just have to work your way through it. You should also try searching from the Windstar front page for your problems. Try "defrost" "defroster" "rear ac" "rear heat"
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