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Discussion Starter #1
I have just gone through my ac and I'm getting a new compressor whine. The condenser I bought said something about being a lower capacity more efficient design. It says to use 2lb 4oz r134a total, but that doesn't bring the low pressure side up to where it needs to be. I tried putting more r134a in but when I get close to the recommended pressure I get a compressor whine. I don't have a high pressure side gauge so I don't know if the smaller capacity is creating higher pressure there.

I don't think the compressor is bad because my ac worked perfectly last year. I just replaced the condenser this year because it had a slow leak. Has anyone had to deal with this same problem?

Also, I replaced the liquid line (oriface tube) and accumulator/drier at the same and I pulled 27hg of vacuum before charging.
 

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The measurement on the condensor is just the amount needed for that piece. The compressor requires a certain amount and the lines and dryer. I don't know why the compressor is whining though. As well as oil, you may require more oil too.
 

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Do you know what the oil capacity is? It should be somewhere between 8-10oz. The store you bought the compressor from should have a book, or I could look it up tomorrow at work.
-Thomas
 

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Discussion Starter #4
It was a little hard to find info but each component got the right amount of oil. The tag just said to use less refrigerant. I believe it was 2 lb 4 oz. I check the high pressure side and got a very high reading. I think I need to buy an oem condenser so the system functions correctly.
 

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The is also a filter in line too. Did you replace or clean it?
 

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OK first off how are you determining the correct pressure on the low side? there is no 1 pressure.

2: did you install a new compressor? did you flush the complete system?

if you replaced (condesor, filter/dryer, Lines) then you removed alot of the systems oil! you will need to add about 2-4oz of oil. this would cause the wine you say you have.

I am assuming that you are converting to 134a,, in this case I hope you change compressors because the stock seals will not last long at all. also you should have added a SmartVov or VOV variable as it almost a neccesity with 134a conversions.

If you need any info drop me a line. I'm a HVAC tech.

Brad M
 

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Discussion Starter #7
1. Using a pressure gauge on the low side I attained 44psi.

2. Old compressor, and the system was flushed.

3. I drained all theoil from the system and added a total of 8.5oz distributed among the components.

I need to get my hands on a high pressure line gauge.
 

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44psi at 80-85* outside temp is good.

Is the low side sweating back cold at the accumulator dryer?

the temp inside the vehicle should start getting cold,, however it wont get cold till you drive it because of not having a VOV,, the standard one just allows to much freon to pass.

Brad
 

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The condenser you got is probably desinged to help make R134a work better in a old R12 system. R12 works at a lower high side pressure than R134a. So when you put R134a in a R12 system the high side will not be high enough to make the R134a work efficently. To get the higher pressuere the R134a systems get they use a pump that flows more freon. So to make R134a work more efficently in a R12 system you need to make it work efficently at the lower flow rate that the old R12 compressior puts out. Sounds like this is what the new condenser you got is tring to do and to do this it requires less freon in the system. 44 psi on the low side is a little high. 35 psi would be more efficent. The higher the lowside pressure the higher the highside pressure will be. But to mush on the high side and you will lose efficencey and the more strain you put on the compressor. And the old compressiors are not designed for the higher pressures that R134a works at. So you have to be more careful with how much freon is put in. You need enough to make the R134a work but not so much that the compressior is strained. 10% less R134a than what the system calls for in R12 is the normall amount. This condenser may call for even less like mabey 20% less. Hope this helps.
 
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