A/C hookup info
 

does anyone know if there is a way to connect standard R-134A hoses to the S8, I see the high side port on the front condenser, and have found a low side fitting that is threaded on the front drivers cowl, is there any other low side quick connect on this system, or are there adapters available to change the threaded low side to a quick connect? Im sure the dealer has some special equipment, but I work at a Ferrari dealer, and we have R-134A service equipment, and would hate to have to go to the Audi dealer for something I could do on my own. ..... Any help?

Do you have an evacuation pump and scale?
 

If so, follow the Bently procedures with the car off, evacuate the system and then load 800 grams of refrigerant.

Re: Do you have an evacuation pump and scale?
 

I do, we have a Sun AC machine, along with raw gauges and a pump and scale, I could do it either way., what would really make my life easy, is if there were a quick connect on the low side of the system, that way I can pull the whole thing down, see what I have in there, and refill it, and draw it in from the low side. Id hate to use just the high side and find that I cant get the required amount in at the last few oz. due to the higher pressure on that side of the system. Would you or anyone happen to know if the threads on the adapters that are made to convert an R-12 system to R-134A will thread onto that low side fitting up by the wondshield, that way I can just use the machine?

Either do it your way or do it per the procedure
 

I have posted the procedure here before. You do it with the engine secured and through the high pressure fitting.

Do it however you'd like, but I recommend doing it in accordance with the Bently procedure.

Re: Either do it your way or do it per the procedure
 

My question is this, is there any other hookup for the low side besides the threaded valve at the cowl, are there any adapters that can be used to make that a quick connect for standard 134 hoses, and finally, does the dealer use a special ac machine to charge through the high side only, or do they use standard ac equipment. Its been my experience that once a system is evacuated, and a vaccuum drawn and held, the new refrgereant can be pulled in via the vaccuum through both high or low side or both, then the last 30% lets say, will get drwan in through the low side, after closing the high side. Also, there is no sight glass on the system is there?

I'm not going to answer all your questions
 

Why dont' you get a Bently manual and learn about the car??? You could either blow something up in the system and have it cost you an arm and a leg or just pay $75 and get the manual.


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A/C refrigerant system (R-134a), discharging
WARNING!

â**? Always use an Underwriter's Laboratory (UL) approved refrigerant recovery/ recycling/recharging unit such as Kent-Moore ACR4, or equivalent, whenever discharging an R-134a A/C system.
â**? Any person who services a motor vehicle air conditioner MUST, by law, be properly trained and certified and use approved refrigerant recycling equipment. Technicians must complete an EPA approved recycling course to be certified.
â**? State and local governments may have additional requirements regarding air conditioning servicing. Always comply with state and local laws.
â**? Always wear safety goggles when discharging, evacuating or recharging an A/C system.
CAUTION!

â**? Always use separate refrigerant recovery/recycling/recharging servicing equipment for R-12 and R-134a systems. DO NOT use one piece of equipment for both R-12 and R-134a systems. The residual traces of refrigerant inside the equipment will contaminate and damage the equipment. Servicing equipment includes recovery/recycling/recharging unit, charging station, vacuum pump, manifold gauges, etc.
â**? DO NOT use R-12 servicing equipment on R-134a systems or R-134a equipment on R-12 systems or damage to both the vehicle A/C system and servicing equipment may result. Use only equipment designed to meet Society of Automotive Engineers (SAE) standards.
â**? R-134a and R-12 systems use different size service fittings. NEVER use adaptors to convert an R-12 fitting to R-134a size or R-134a fitting to R-12 size.
Note:

Follow all safety measures starting on page 87-1, when discharging an A/C refrigerant system.



Discharging

Make sure initial set-up has been performed on recovery/recycling/recharging unit before discharging A/C system.

‧ ↧ Connect red high pressure hose -A- of refrigerant recovery/recycling/recharging unit to high pressure service valve (fitting) on vehicle and open coupler valve.
‧ Leave blue low pressure hose -B- of refrigerant recovery/recycling/recharging unit disconnected.
Note:

Only a high pressure service valve is used for A/C system servicing. A low pressure service valve is not installed in the A/C system. Perform all A/C system service operations (i.e. discharging, evacuating and charging) through the high pressure service valve only.

CAUTION!
Always follow manufacturer's instructions when using a refrigerant/recovery/recycling/recharging unit.
‧ Following refrigerant recovery/recycling/recharging unit manufacturer's instructions, discharge A/C system into refrigerant recovery/recycling/recharging unit.
‧ After emptying A/C system, disconnect power supply from A/C clutch -N25- (e.g. unplug connector from A/C refrigerant low pressure switch -F73-) to prevent accidental compressor operation with A/C system discharged.

--------------------------

A/C refrigerant system (R-134a), evacuating & recharging
WARNING

â**? Always use an Underwriter's Laboratory (UL) approved refrigerant recovery/ recycling/recharging unit such as Kent-Moore ACR4, or equivalent, when evacuating and recharging an R-134a A/C system.
â**? Any person who services a motor vehicle air conditioner MUST, by law, be properly trained and certified and use approved refrigerant recycling equipment. Technicians must complete an EPA approved recycling course to be certified.
â**? State and local governments may have additional requirements regarding air conditioning servicing. Always comply with state and local laws.
â**? Always wear safety goggles when discharging, evacuating and recharging an A/C system.
CAUTION!
Always follow manufacturer's instructions when using a refrigerant/recovery/recycling/recharging unit.
Note:

Only a high pressure service valve is used for A/C system servicing. Perform all A/C system service operations (i.e. discharging, evacuating and recharging) through the high pressure service valve only.

Evacuating & recharging

Follow all safety measures starting on page 87-1, when evacuating and recharging the A/C refrigerant system.

‧ Follow refrigerant recovery/recycling/recharging unit manufacturer's instructions for evacuating and recharging A/C system.
‧ Evacuate refrigerant system for a minimum of 30 minutes.
‧ When recharging A/C system, add correct amount of refrigerant and PAG oil to system, see A/C refrigerant system capacities => page 87-202.
‧ After system recharge, manually rotate A/C compressor approx. 10 turns before starting engine. Start engine with A/C OFF. After idle speed has stabilized, switch A/C ON and let engine idle (compressor running) for a minimum of two minutes before raising engine speed.

Re: I'm not going to answer all your questions
 

Thanks for printing all that for me, I appreciate it.

Re: I'm not going to answer all your questions
 

I have never seen a sight glass in a R134a system.
Too bad, they were sort of reassuring, especially if they had indicator paper to show if there was moisture present.

Re: I'm not going to answer all your questions
 

I spoke with a friend of mine at the audi dealership, and he said that there is no sight glass on the system, and that they do all of the A/C serviceing through the high side of the system, there is no quick connect on the low side. No special equipment needed. The thing I dont understand is how are you supposed to fully check the performance of the system if you can only work off the high side? It would be nice to be able to check low side pressures as well, but then again, Im not German so maybe Im missing something.

Re: I'm not going to answer all your questions
 

They save a buck, I guess. You certainly have less diagnostic info, e.g., a low low side along with a too high high side if the metering device is blocked. It is also no longer possible to equalize pressures across the compressor valves by bleeding through the gauge set.

I use my wife's digital cooking thermometer in the vents.