A/C Experts?

[delboy]

Anyone with experience replacing a/c components?

I'm replacing, accumulator, liquid line and evaporator. Do i need to add oil before hooking the new components up, if so how much to which components, and what type of oil?

Thanks
Derek

[Bulldog 6]

When I worked on my Mustang A/C, I added 1 can of R134A with oil and then topped off the system with straight R134A. THe oil should mostly sit in the compressor. If you are replacing components because of a leak then you should add some oil in. THe 134 can with oil should be sufficient. If your system grenaded itself then it would probably be a good idea to change the oil in the compressor. Not sure how to do this on a car system. Industrial is just a mtter of removing the plug and draining. THis is common in the industrial systems as compressors are quite often interchangable with freon types. Just a matter of putting the correct oil in the compressor.

When I did the Mustang, I was changing the heater core and had to drain the A/C. My HVAC techs at work told me that the 134 w/oil should be plenty. Just make sure to cap any disconncted lines during the install and have the system evacuated prior to recharging.

[pk]

the entire system after assembly still must be evacuated of all the moisture. the ND-8 PAG oil in 134-A systems is so highly refined that exposure to open air will cause it to absorb 5.6% of its own weight in moisture. this includes the air that is trapped in the system from a home assembly.


the amount for your vehicle's year and make are 8.0 ounces oil, 28 ounces refrigerant assuming your vehicle was made after jan 1 1994. prior to this, it was R-12 and should be converted.

Edit: you maybe could also go with the SP-20 PAG oil. not sure.... but, the ND-8 is synthetic

[TiggersBounce]

I had my neighbour bring his van over after I replaced the condenser. He is an HVAC guy.
First he removed the shraeder valve core on the low pressure port and used a syringe to squeeze in 1 oz of ISO 46 PAG oil to make up for the new condenser, and replaced the valve core.
Then he hooked up the manifold gauge set to pressurize the system with nitrogen to do an audible leak test.
Then connected his vacuum pump and pulled it down to ~0.1 mm Hg absolute, closed the valves and let it sit for 20 mins to see if the gauge moved.
Since it held, he connected up his keg of 134a and filled the system.
Then inserted thermometers in the dash vents and ran the system to see if it was achieving the proper temperature drop.

And for all this I gave him a beer.

Like pk says, if you replaced components, you want to have the system evacuated before recharging.

oil:
ND8 PAG = ISO 46
accumulator, 4 oz if replaced
condenser, 1 oz " "
evap core, 2 oz " "