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  #1  
Old 05-11-2009, 12:24 AM
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AC question

o my AC system is showing about a 35 on the gauge when I hook it up, psi I am guessing (no I am not an a/c guru as you can see). It blows hot air on the drivers side, and used to blow cold on the right side, now it is only room temp though. The compressor is kicking on, the aux fans are going. I know I have seen on here that the r-134 systems are filled by weight, but other than a low charge, what would make it blow warm air? Especially on just 1 side?

Talking about the 96 by the way.

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  #2  
Old 05-11-2009, 01:05 AM
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Inarticulate Speculation

Duo Valve ? (Heater Control Valve,regulates the HOT coolant that Warms P.C)
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  #3  
Old 05-11-2009, 10:43 AM
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It's probably low on refrigerant. The pressure when not running means nothing. The pressure when it is running means a bit more, but not without knowing a bunch of other things, one of which is the high-side pressure.

Throw away that cheap recharge hose and get some real equipment. Including a thermometer.
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Old 05-11-2009, 11:00 AM
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Quote:
Originally Posted by Biglex View Post
o my AC system is showing about a 35 on the gauge when I hook it up, psi I am guessing (no I am not an a/c guru as you can see). It blows hot air on the drivers side, and used to blow cold on the right side, now it is only room temp though. The compressor is kicking on, the aux fans are going. I know I have seen on here that the r-134 systems are filled by weight, but other than a low charge, what would make it blow warm air? Especially on just 1 side?

Talking about the 96 by the way.
Got exactly the same results that you mention, along with a hissing sound coming from the center vent with the ac on. AC unit needed a little recharge, and all is well. Hopefully that is the same cure for your issue. Good luck!
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Old 05-11-2009, 11:16 AM
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" Hissing sound from the center vent...."
I am not sure we can categorically call that a good sign... until we know what is causing it...
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  #6  
Old 05-11-2009, 01:04 PM
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I tested it with good equipment, with the system running, on the low side. Don't need a thermometer to tell me the ac isnt cold.


Quote:
Originally Posted by Matt L View Post
It's probably low on refrigerant. The pressure when not running means nothing. The pressure when it is running means a bit more, but not without knowing a bunch of other things, one of which is the high-side pressure.

Throw away that cheap recharge hose and get some real equipment. Including a thermometer.
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  #7  
Old 05-11-2009, 01:05 PM
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I have that same hissing sound. I will take it to the a/c shop and get a recharge.


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Originally Posted by pimpernell View Post
Got exactly the same results that you mention, along with a hissing sound coming from the center vent with the ac on. AC unit needed a little recharge, and all is well. Hopefully that is the same cure for your issue. Good luck!
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Old 05-11-2009, 03:00 PM
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Were you working on the system or just checking?
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  #9  
Old 05-11-2009, 04:03 PM
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The hissing from center vents on a W210 usually means it is low on refridgerant.

Why not get the AC actual values from the CCU and also pull error codes?
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  #10  
Old 05-11-2009, 09:07 PM
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Quote:
Originally Posted by leathermang View Post
" Hissing sound from the center vent...."
I am not sure we can categorically call that a good sign... until we know what is causing it...
I assume that it's a W210. They do that when low on refrigerant. It is quite noticeable.
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Old 05-11-2009, 09:09 PM
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Originally Posted by Biglex View Post
I tested it with good equipment, with the system running, on the low side. Don't need a thermometer to tell me the ac isnt cold.
The high-side pressure is very important. The thermometer is for measuring the air entering the condenser, as well as the actual vent temperature. The relative humidity in the cabin is a good idea too, but you can usually get away with guessing at that one (it doesn't change the pressure that much).
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  #12  
Old 05-12-2009, 02:33 AM
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It is the 210. How can I get the actual values from the CCU?

I have not checked the high side, just the low. I will get on that as soon as I can.
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  #13  
Old 05-12-2009, 02:34 AM
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Originally Posted by dannym View Post
Were you working on the system or just checking?
Just checking. I can't do much with these cars. Almost always have to take it to the shop.

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