Getting ready to use new A/C system
04-17-2013, 09:05 PM
#1
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Getting ready to use new A/C system
Found out the information I needed on how to adjust the clutch cycling switch. Now I just need to know the proper information on assembling all the components.
The A/C in my car was long gone when I purchased it 5 years ago. I'd guesstimate that it hasn't had functioning A/C for around 6 years now. The condenser had been removed as had the lines and drier. The compressor remained bolted to the engine with the belt detached and the rear ports left wide open. I knew I couldn't put any faith into that compressor and during my header install I completely destroyed the evaporator by knocking a large gaping hole in the side of the heater box and puncturing the evap core so it looked like I was in the market for a completely new system.
I purchased a new aluminum housing R4 compressor strong enough to run vehicles equipped with rear A/C. The compressor came with a new orifice tube, drier and a set of R134a compatible seals. I also purchased a new condenser and a new set of suction/discharge lines. The only part of the system that is not new is the evaporator core. My friend was installing an A/C delete heaterbox on his firebird. The evaporator core and the heater box cover were in perfect shape and the car only had 40k original miles on it, so I figured that would save me $70 - $100 and figured why not. I have read some bad stuff on having the A/C system flushed, So I am going to just run around 80 - 100psi of compressed air through the evaporator to blow out any excess mineral oil from the original R12 charge as well as any debris that may have found it's way in before bolting everything up.
I am going to have a shop pull a vacuum on the system for 1 hour before charging but I wanted to know the process on adding PAG oil to completely new system with dry components. Does it all go straight into the compressor or should it be added to the components separately?
The A/C in my car was long gone when I purchased it 5 years ago. I'd guesstimate that it hasn't had functioning A/C for around 6 years now. The condenser had been removed as had the lines and drier. The compressor remained bolted to the engine with the belt detached and the rear ports left wide open. I knew I couldn't put any faith into that compressor and during my header install I completely destroyed the evaporator by knocking a large gaping hole in the side of the heater box and puncturing the evap core so it looked like I was in the market for a completely new system.
I purchased a new aluminum housing R4 compressor strong enough to run vehicles equipped with rear A/C. The compressor came with a new orifice tube, drier and a set of R134a compatible seals. I also purchased a new condenser and a new set of suction/discharge lines. The only part of the system that is not new is the evaporator core. My friend was installing an A/C delete heaterbox on his firebird. The evaporator core and the heater box cover were in perfect shape and the car only had 40k original miles on it, so I figured that would save me $70 - $100 and figured why not. I have read some bad stuff on having the A/C system flushed, So I am going to just run around 80 - 100psi of compressed air through the evaporator to blow out any excess mineral oil from the original R12 charge as well as any debris that may have found it's way in before bolting everything up.
I am going to have a shop pull a vacuum on the system for 1 hour before charging but I wanted to know the process on adding PAG oil to completely new system with dry components. Does it all go straight into the compressor or should it be added to the components separately?
04-19-2013, 07:59 AM
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Re: Getting ready to use new A/C system
Hi there 
I completed an R134A retrofit last year on my 5.7 Iroc 88 and it was good learning curve.
Regarding your question on adding PAG oil. I believe these Harrison compressors take PAG 100 but please check that. Add a small amount (an oz or two ) direct to the compressor. This will ensure it isn't totally dry the first time you fire it up. Turn the compressor by had a few revolutions to move the oil through (this will avoid any hydrolock when you first run the compressor) The rest of the oil can be added through the low side port with a manual oil injector. I also added some UV dye to the oil in case I developed a leak in the future.
Then you can go to a shop and have a vac pulled on the system and add your R134a, adjust your pressure switch and enjoy having a working A/C
I completed an R134A retrofit last year on my 5.7 Iroc 88 and it was good learning curve.
Regarding your question on adding PAG oil. I believe these Harrison compressors take PAG 100 but please check that. Add a small amount (an oz or two ) direct to the compressor. This will ensure it isn't totally dry the first time you fire it up. Turn the compressor by had a few revolutions to move the oil through (this will avoid any hydrolock when you first run the compressor) The rest of the oil can be added through the low side port with a manual oil injector. I also added some UV dye to the oil in case I developed a leak in the future.
Then you can go to a shop and have a vac pulled on the system and add your R134a, adjust your pressure switch and enjoy having a working A/C
04-19-2013, 08:57 AM
#3
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Re: Getting ready to use new A/C system
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Se post #3.
Don't think there's much left to say about it...
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Don't think there's much left to say about it...
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