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A/C Compressor replacement

z71 BLaCkMaMba
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z71 BLaCkMaMba Enthusiast

z71 BLaCkMaMba

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I had a locked up ac compressor decided to replace that along with new condenser, and expansion valve. My buddy and I measured the oil from the old compressor and dumped out the new compressor oil and added what was in the original compressor. Vacuumed for about a hour added freon felt better than the original thought the job was done drove about 2 miles and started to blow hot heater like air. Thought we had overcharged it so we took it to a place that has the machine and had it recovered no leaks. The guy added the correct amount of oil and freon it was cooling but not really as cold as it was before.  Then the next morning I turned it on it was just blowing hot air only blew out cold air when I was driving. Low Pressure was reading about 70psi and high was about 200psi. I recovered the freon got it down to 40psi fans kicked on and it began to somewhat cool again. Well same thing the next morning happened PSI was at 80 on the low side? Any ideas what too look at next?

btj_z71 Enthusiast

btj_z71

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5 minutes ago, z71 BLaCkMaMba said:

I had a locked up ac compressor decided to replace that along with new condenser, and expansion valve. My buddy and I measured the oil from the old compressor and dumped out the new compressor oil and added what was in the original compressor. Vacuumed for about a hour added freon felt better than the original thought the job was done drove about 2 miles and started to blow hot heater like air. Thought we had overcharged it so we took it to a place that has the machine and had it recovered no leaks. The guy added the correct amount of oil and freon it was cooling but not really as cold as it was before.  Then the next morning I turned it on it was just blowing hot air only blew out cold air when I was driving. Low Pressure was reading about 70psi and high was about 200psi. I recovered the freon got it down to 40psi fans kicked on and it began to somewhat cool again. Well same thing the next morning happened PSI was at 80 on the low side? Any ideas what too look at next?

Holy s***.  80 and 70 PSI is WAY to high for the low side. If you didnt have any leaks before, you likely will have some now.  Low side PSI should be around 30-35PSI if the outside temp is 90F. High side should be around 110 -120PSI

 

z71 BLaCkMaMba Enthusiast

z71 BLaCkMaMba

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Yeah I know that was way too high I wasn't sure what would cause that to be that high though when we had charged it it was at about 45psi on low side then the next day it shot up to 70-80psi.  So correct reading should be about 30-35psi?  Right now in Texas its about 100+degrees.  On a chart I saw it said the freon should be at about 50-55 off the ambient temperature chart.  Thanks for the reply I will see how it does at 30-35 psi 

Snowcamo Senior Enthusiast

Snowcamo

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You need to replace the drier bag. See pics. This is a one time use item. When the system is opened this has to be replaced.c5167fab45054f1f1e10e31f7697d3dc.jpg94e1b9f832f842d0d9bc72ea236962ed.jpg

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z71 BLaCkMaMba Enthusiast

z71 BLaCkMaMba

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Thanks for the help!  When I purchased the GPD 4283C condenser I called the company and they said a brand new drier was built in the condenser.  I wanted to double check that but I didn't want to break the seal I called 3 times and 3 different guys told me it was already installed in there.  

Snowcamo Senior Enthusiast

Snowcamo

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Ok great then your next item is the expansion valve. If it failed then it would take out the comp. If your not cooling then the compressor isn't then lockups happen or it could just have flooded the comp with liquid.

z71 BLaCkMaMba Enthusiast

z71 BLaCkMaMba

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42 minutes ago, Snowcamo said:

Ok great then your next item is the expansion valve. If it failed then it would take out the comp. If your not cooling then the compressor isn't then lockups happen or it could just have flooded the comp with liquid.

Thanks bud but this was doing that with a brand new after market expansion valve and I removed it and put the original one back on didn't have any contaminants and still did the same thing...Idk man today when I get home from work I am going to release some freon lol its at 40psi last checked maybe the other guy who gave me some advice might be right it should be at 30-35 psi.  Thanks again man

Snowcamo Senior Enthusiast

Snowcamo

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Thanks bud but this was doing that with a brand new after market expansion valve and I removed it and put the original one back on didn't have any contaminants and still did the same thing...Idk man today when I get home from work I am going to release some freon lol its at 40psi last checked maybe the other guy who gave me some advice might be right it should be at 30-35 psi.  Thanks again man
It should be in the 30s for sure. Did you guys not weigh it in?

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z71 BLaCkMaMba Enthusiast

z71 BLaCkMaMba

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1 minute ago, Snowcamo said:

It should be in the 30s for sure. Did you guys not weigh it in?

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When we first did it we just went off of ambient temperature sheet and got the pressure to about 50-55 thats when it wasn't cooling good and took it to a place that has a machine and they weighed it in along with the pag oil.

z71 BLaCkMaMba Enthusiast

z71 BLaCkMaMba

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19 hours ago, btj_z71 said:

Holy s***.  80 and 70 PSI is WAY to high for the low side. If you didnt have any leaks before, you likely will have some now.  Low side PSI should be around 30-35PSI if the outside temp is 90F. High side should be around 110 -120PSI

 

I think 30-35 was the magic numbers bro thanks cooled and even cooled on a cold start! thanks bud

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