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a/c blows cold then hot

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  #1  
Old 09-19-2009, 08:07 AM
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Default a/c blows cold then hot

Not to familar w/Honda a/c's, but what would cause the a/c to blow hot?

Doesn't matter if the car is stopped or moving, I checked the heat valve and seems to be ok.

TIA
 
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Old 09-19-2009, 08:45 AM
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How about some more information. I recently had problems with my A/C and the good people on this forum helped me find the cause. How long does it blow cold before hot? Does it ever start to blow cold again? Does it make a difference if you're in town vs on the highway? What exactly is happening?
 
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Old 09-19-2009, 09:50 AM
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It will blow cold again and there seems to be no rhyme or reason, I can be stopped at a stop sign and it will blow hot or I could be doing 50.
It will usually blow cold from anywhere between 5-10 minutes, then turn hot and when it blows hot, it can be from a minute to 15 minutes before it will turn cold and it turns cold slowly.
 
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Old 09-19-2009, 10:22 AM
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Drive until it starts blowing hot. Pull over and with the engine still running and the A/C button pressed, check if the compressor is engaged. Also check if the condenser fan is running.
 
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Old 09-19-2009, 10:41 AM
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Thanks, will try that.
 
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Old 09-19-2009, 11:05 AM
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Ok, the a/c stayed running the whole time, including the fan.
Air started coming out the defroster vent after about 7-8 min., with a trickle to the dash vents.
No matter what button I pushed for flow control, the air came out the top, with the exception of when I pushed the floor vent button, that turned the air to the floor.

Also noted, the air was not blowing as cold when hot as it was when the engine was cold.
 
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Old 09-19-2009, 11:07 AM
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One other thing, are there any vacuum hoses for vent control?
The car has 200k+ and my daughter really needs a/c living in FL.
 
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Old 09-19-2009, 03:47 PM
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What model year? I'm pretty sure no Civics use vacuum for the flow controls, it's either mechanical (before 1992) or electric. After about 1998 the system has a self-test function.
 
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Old 09-19-2009, 04:33 PM
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Sorry it is a 95 EX.
Could the contacts on the buttons be corroded and cause this.
My Corvette buttons sometimes act up and I have to clean them about every 7-8 yrs.
 
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Old 09-20-2009, 05:25 AM
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I have not heard of a problem with randomly changing before. There are really only two parts involved, the control panel and the motor. The motor is on the side of the heater box in the center of the car, you can reach it reaching up from the driver's floorboards. A temporary fix might be to get the air coming out of the face vents like you want, then unplug the motor so it can't change.
 


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