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just replaced and serviced a/c and its not cold??

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Old 06-22-2011 | 05:45 PM
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Well that was a huge fail!!! It Got worse. The temp may have been 10 degrees cooler than out side....

WTH!!!
Old 06-23-2011 | 02:15 AM
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does anyone have any other ideas?
Old 06-23-2011 | 02:30 AM
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Possibilities:
-- Bad expansion valve (stuck in one position)
-- still overcharged? proper pressures vary with ambient temp
-- heat being added by heater core (pinch heater hose off)
-- condenser full of crap (air side)
-- Evaporator full of crap (would reduce airflow, not too likely)
-- bad compressor
Old 06-23-2011 | 01:42 PM
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Well, that narrowed it down.... The cleaned out the condenser and evaporator. Compressor is working.... I will check the heat thing but I'm pretty sure it's the expansion valve...
Old 06-23-2011 | 01:53 PM
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"the low side was 26-30 and the high side is 165ish..... "

This seems very low to me... mine was 35 low and 215 high <--- or something like that... I remember i was aiming for 225 high.
See Clarks Garage... and as you said: lowering the pressure made it worse..

http://www.clarks-garage.com/shop-manual/hvac-02.htm

Last edited by pnbell; 06-23-2011 at 02:08 PM.
Old 06-23-2011 | 02:50 PM
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It depends what the outdoor temp is, if it's 95 out, all pressures will be higher.

When you say they cleaned out the condenser, do you mean they flushed it, or they cleaned all the bugs and rocks out of the fins?

I'd focus on the expansion valve, it should be relatively easy to tell if it's stuck. I'm not sure what type is in your car, but if it's the kind with a capillary tube over to the evaporator, it would be very suspect.
Old 06-23-2011 | 03:30 PM
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I cleaned the outside yesterday and flushed it before i installed it... i flushed it with water then used compressed air to dry it out.....

its a 90 degree peice with one coper tube coming off that is clamped to the tube... when i had it off i could blow through it so assumed it was good since it wasnt clogged....
Old 06-23-2011 | 05:12 PM
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I'd bet your EV is stuck in one position. That small copper capillary tube should be wrapped with insulation, usually a tarry kind of tape, where it is clamped to the pipe.

Did you flush the inside of the tubes of the condenser with water?
Old 06-23-2011 | 06:37 PM
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i put the EV back on the same way it came off so whatever it hooked to before... it was covered in tar like stuff but is not right now.

i did flush the condensor with water but i also ran compressed air through it and it sat for 3 days before i installed it...
Old 06-23-2011 | 08:01 PM
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Using an air compressor is a big no no, flushing with water is even worse, you will probably need to recover the R134a, replace the dryer since water in the system would render it useless,maybe need to replace the condensor as well, draw a vacuum on it for an hour, see if it holds 30" of vacuum for an hour then recharge the system, if your lucky this might work.
Old 06-23-2011 | 08:20 PM
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Usually if you draw a vacuum long enough it sucks all the condensation/water out of the system right?
Old 06-23-2011 | 08:53 PM
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Originally Posted by 86 951 Driver
Usually if you draw a vacuum long enough it sucks all the condensation/water out of the system right?
Yes, but if you live in a humid climate, and the system was open to air for an extended period, it will have enough water that its just easier to replace the receiver/drier. It would take many hours to boil off that much water.


We're not talking oz. of water. We're talking humidity in the air.... tiny amounts of water will cause an ac system to either not work, or fail (break).
Old 06-23-2011 | 09:15 PM
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The water will also freeze in the EV, blocking it and/or locking it in position. Toss that drier.

It would be very hard to get all the water out of the condenser if you flushed it with water, and unless the compressed air used to blow it out was dried air, it would be adding oil and moisture to the mix. I'd be tempted to flush the condenser with A/C system flush off the car.

That's a good point too, where do you live, Dice? If you're in Houston, more than half your system's capacity is going to dehumidification of the air. It isn't going to be as cold as in the desert.
Old 06-23-2011 | 10:37 PM
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Flushing with water was not a good idea. I'm leaning toward bad expansion valve too and re-flush the system with a product made for flushing. I've read that even blowing non-filtered/dried compressed air through the system is a bad idea much less water...
Old 06-23-2011 | 10:38 PM
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ok..... maybe i wasnt clear enough? the condensor was off the car, cleaned and let to dry. THEN i put a NEW dryer on and the NEW compressor and the clean condensor..... then when serviced it was vacuumed for 45 min. no water is in the system and its not clogged.... i live in North Carolina

i put some R134 back in today and it is working better than yesterday but still not right.... i am getting a new EV and trying that...


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