AC High Side Pressure - AC System Rebuild/Repair
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AC High Side Pressure - AC System Rebuild/Repair
So, I'm going to start at the beginning so this will be a little longer than read than it should, but here's all the details.
The compressor starting making noise when in use around 5-6 months ago, sounded like I had a blower under the hood. The system had never been opened or modified, to the best of my knowledge.
4 months ago I replaced my stock radiator with the LT1 unit and the hard line from the top of the condenser to the evaporator that houses the orifice tube decided to break. I have pulled the radiator out of the car probably 5-6 times over the previous 2 years doing various engine mods stressing that line every time so it was just a matter of time before the aluminum failed. Since it was starting to get cold, I figured I would just replaced that line, flush the hoses and condenser, pull a vacuum and refill the system with oil and freon to get me through the winter.
Well that lasted me til a few days before Halloween because the schrader valve on the accumulator decided to leak all of my freon out. I replaced the schrader valve around the end of November and went to recharge the system when I couldn't get the compressor to kick on. It was late and I didn't feel like bypassing the clutch so I didn't mess with it until two weeks ago.
Two weeks ago, I bypassed the compressor clutch, filled the system up with oil and freon and it worked great, for about a week. I noticed the low side cap had a lot of dye around it so I figured the schrader valve had leaked again so I bought a new accumulator and orifice tube to rule out the schrader valve entirely. During this past week when I wasn't getting any cold air, the compressor would turn on with AC request but I would not get any cold air and the compressor wasn't making any noise but the clutch was engaged and turning with the engine. So, I went to purge the little bit of freon left in the system to replace the accumulator and orifice tube. The purge process took over 10 minutes so the system was full of freon and it had not leaked out of the schrader valve. I then figured my compressor committed suicide.
So yesterday, after $600 worth of new parts (new compressor, accumulator, flush chemicals, freon, oil, orifice tube, and o-ring kit), I filled it up with 9 oz. of PAG-150 and 24 oz. of R134-a.
Down to the question, I have done AC work on quite a few cars, and they all work great to do this day (some 2+ years). I must be doing something right. I have always followed the rule that the high side pressure should be about 2.5X the ambient temperature. Upon filling every other system to recommended capacity and every time I've done this system, that has held true. Last night the temperature was about 70F so I should have seen around 175# on the high side but I was only seeing around 130-140#. The system is blowing cold and everything seems to be working properly, just wondering why this time it is different. Thoughts...? Maybe the compressor is breaking in?
Some compressor suicide pictures for your viewing pleasure. FYI, the black death orifice tube is only 4 months old.
The compressor starting making noise when in use around 5-6 months ago, sounded like I had a blower under the hood. The system had never been opened or modified, to the best of my knowledge.
4 months ago I replaced my stock radiator with the LT1 unit and the hard line from the top of the condenser to the evaporator that houses the orifice tube decided to break. I have pulled the radiator out of the car probably 5-6 times over the previous 2 years doing various engine mods stressing that line every time so it was just a matter of time before the aluminum failed. Since it was starting to get cold, I figured I would just replaced that line, flush the hoses and condenser, pull a vacuum and refill the system with oil and freon to get me through the winter.
Well that lasted me til a few days before Halloween because the schrader valve on the accumulator decided to leak all of my freon out. I replaced the schrader valve around the end of November and went to recharge the system when I couldn't get the compressor to kick on. It was late and I didn't feel like bypassing the clutch so I didn't mess with it until two weeks ago.
Two weeks ago, I bypassed the compressor clutch, filled the system up with oil and freon and it worked great, for about a week. I noticed the low side cap had a lot of dye around it so I figured the schrader valve had leaked again so I bought a new accumulator and orifice tube to rule out the schrader valve entirely. During this past week when I wasn't getting any cold air, the compressor would turn on with AC request but I would not get any cold air and the compressor wasn't making any noise but the clutch was engaged and turning with the engine. So, I went to purge the little bit of freon left in the system to replace the accumulator and orifice tube. The purge process took over 10 minutes so the system was full of freon and it had not leaked out of the schrader valve. I then figured my compressor committed suicide.
So yesterday, after $600 worth of new parts (new compressor, accumulator, flush chemicals, freon, oil, orifice tube, and o-ring kit), I filled it up with 9 oz. of PAG-150 and 24 oz. of R134-a.
Down to the question, I have done AC work on quite a few cars, and they all work great to do this day (some 2+ years). I must be doing something right. I have always followed the rule that the high side pressure should be about 2.5X the ambient temperature. Upon filling every other system to recommended capacity and every time I've done this system, that has held true. Last night the temperature was about 70F so I should have seen around 175# on the high side but I was only seeing around 130-140#. The system is blowing cold and everything seems to be working properly, just wondering why this time it is different. Thoughts...? Maybe the compressor is breaking in?
Some compressor suicide pictures for your viewing pleasure. FYI, the black death orifice tube is only 4 months old.
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What is the vent temp and low side reading? Is it pulling down to 30 - 35 or lower on low side?
With your condenser fan on and ambient temp at 75* I think 140 # on high side is ok, pending your low side is correct...
Keep in mind too that the hoses on your gauge set will hold freon as well. I use 2-4 ounces more than vehicle specs because of that amount still being in hoses when I'm done, so you might be slightly undercharged as well.
With your condenser fan on and ambient temp at 75* I think 140 # on high side is ok, pending your low side is correct...
Keep in mind too that the hoses on your gauge set will hold freon as well. I use 2-4 ounces more than vehicle specs because of that amount still being in hoses when I'm done, so you might be slightly undercharged as well.
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I am using a manifold gauge set, no machine. I am using DuPont R-134a freon from the parts store.
What is the vent temp and low side reading? Is it pulling down to 30 - 35 or lower on low side?
With your condenser fan on and ambient temp at 75* I think 140 # on high side is ok, pending your low side is correct...
Keep in mind too that the hoses on your gauge set will hold freon as well. I use 2-4 ounces more than vehicle specs because of that amount still being in hoses when I'm done, so you might be slightly undercharged as well.
With your condenser fan on and ambient temp at 75* I think 140 # on high side is ok, pending your low side is correct...
Keep in mind too that the hoses on your gauge set will hold freon as well. I use 2-4 ounces more than vehicle specs because of that amount still being in hoses when I'm done, so you might be slightly undercharged as well.
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So yesterday, after $600 worth of new parts (new compressor, accumulator, flush chemicals, freon, oil, orifice tube, and o-ring kit), I filled it up with 9 oz. of PAG-150 and 24 oz. of R134-a.
Down to the question, I have done AC work on quite a few cars, and they all work great to do this day (some 2+ years). I must be doing something right. I have always followed the rule that the high side pressure should be about 2.5X the ambient temperature. Upon filling every other system to recommended capacity and every time I've done this system, that has held true. Last night the temperature was about 70F so I should have seen around 175# on the high side but I was only seeing around 130-140#. The system is blowing cold and everything seems to be working properly, just wondering why this time it is different. Thoughts...? Maybe the compressor is breaking in?
Down to the question, I have done AC work on quite a few cars, and they all work great to do this day (some 2+ years). I must be doing something right. I have always followed the rule that the high side pressure should be about 2.5X the ambient temperature. Upon filling every other system to recommended capacity and every time I've done this system, that has held true. Last night the temperature was about 70F so I should have seen around 175# on the high side but I was only seeing around 130-140#. The system is blowing cold and everything seems to be working properly, just wondering why this time it is different. Thoughts...? Maybe the compressor is breaking in?
Best thing for a system with 24 oz capacity is using a 16 ounce can and a 12 ounce can ( I think you can buy 16 ounce cans) . If you were to use two 16 ounce cans then you may be slightly over by an ounce or two if it's hot out but you would be ok. If it's 70F or cooler then i'd use two 16oz cans.
the other thing that i sorta worry is if i understand correctly, you had a compressor failure with debris throughout the system. You mentioned the new parts, but did you replace the condenser ? You definitely need to flush the system, however after complete compressor failure like you had it's recommended to replace the condenser, a flush is not a guarantee that it will be clean.