Troubleshooting Air Conditioner Not Working

Tiny
KEN L
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It will suck some of the oil out but not much like about 1/4 once, next when you take the system apart look and compressor off, look down inside the compressor to see if you see any metal particles this will let you know if there is more of a problem
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
KEVINM01
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Ok, thanks for answering my question about the oil Ken. I'm waiting on a compressor and once I receive it, I'll replace my compressor, condenser, and drop in new AC drier/dessicant.
I know that there is a leak somewhere in the system, but haven't seen dye anywhere looking with UV light and goggles. Also, as I mentioned before, the only place the sniffer was active was in front of the condenser. I asked earlier. Is that normal (to detect refrigerant outside the condenser)?

Now, the part of the AC system I haven't looked at is the evaporator, or its drain tubes, or its housing (only because, I've not been ready to take off my dash etc.). One mechanic I showed the car too agrees that the evaporator drains must empty above the transmission, which is why the drains are not visible looking under the car.
But even if the evaporator has a leak or drain tubes are clogged etc.I should still be able to recharge and pump refrigerant in the system right? That is to say, the manifold gauges should not be showing equal pressures on each side and also, after topping off the system with refrigerant. It should cool, right (even if short-lived)?
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
KEN L
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Its kind of normal for the sniffer to go off on the condenser because you are picking up dust partials which makes for a false reading, is the condenser wet where you get the reading?

Like this?

Second to the last image

https://www.2carpros.com/articles/how-a-car-air-conditioner-works

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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
KEVINM01
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No, my condenser does not look wet. But you do see a bunch of white spots on it, and leaves in it.

Okay. So let's say there's a leak in one of the connections to my evaporator or the expansion valve or a blocked drain tube. Wouldn't one of the hoses to the compressor still feel cold? And wouldn't there still be pressure differential between the High Side/Low Side (which currently there is not)?
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
KEN L
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If there is blockage you will not feel cold, if the compressor is bad it cannot make pressure so there will be no difference in pressure.
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
KEVINM01
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Ok, but let's say there was a blockage somewhere (high side or low side). Wouldn't there be a pressure differential between high side and low side?
So far, pressures have only been equal.
Also, let's say my evaporator drain was blocked. Wouldn't the condensation build up and leak into the cabin? I haven't seen that.

I'm leaning strongly towards just a bad and LEAKY compressor. What do you think?
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
MHPAUTOS
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An internal failure of the comp will often show equalization of high and low side pressures, if this is the case there will be breach between the high and low side internally and high side pressure is leaking into the low side, if the condenser drain is blocked and no condensation can drain away, you would see water spilling but you would have to see a fair build up of condensation for this to happen and also the humidity will have a big effect on this, if you are in a low humility area there is a lot less water in the air to condense in the first place, I have only been looking at this post and adding comments as I feel are warranted, Ken has been running with great advice here, for my 2 bobs worth I feel that the compressor is highly suspect as the main cause of your problem.
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
KEVINM01
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Alright, MHP. Thanks for the detailed answer.
Earlier you said that if there are flakes from the failed comp in the system, this would spell serious disaster.
If it turns out there are metal flakes and other debris within the system. Is there no solution for this?
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Thursday, August 27th, 2020 AT 6:24 PM
Tiny
MHPAUTOS
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In past experience when there has been a comp failure of significant magnitude and there has been debris deposited with in the system, nothing that I have seen has to my knowledge been successful in cleaning the system of all material, in saying that, these have not been marque cars and customers have opted to not repair as the cost often is beyond their means, this is a grey area we are dealing with, a comp, condenser and receiver dryer may do the job with a flush, but this is not a given cure all, you may be lucky and get away with it, or it may work for a few months and start to cause problems again, unfortunately this is a call you have to make.
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Thursday, August 27th, 2020 AT 6:24 PM

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