924S AC compressor reseal successful! 134 pressures?

[Tim Hancock]

Just got the AC in my '87 924S vaccuumed and recharged and it works great!

My Nippondenso compressor had a case leak and I resealed it with a new kit. I also replaced the drier and some other o-rings. I put a couple of ounces of ester oil in the compressor after I reassembled it. Next I pulled a vaccuum for about an hour, then added about 4 more ounces of ester oil thru the charge port, then charged the system with an additional two cans of 134. My low pessure at 2000 rpms is about 20psi and my high pressure is about 225psi. The air temp was about 90 deg. The AC is awesome thus far after one day of driving.

Does anyone know what the optimum high and low pressures are for a 924 or 944 with a Nippondenso compressor running 134? None of my manuals list pressures for AC recharging with 134.

[Razorback1980]

Hey Tim,

I typically shoot for 210 to 215 and 25 to 30 on the a/c systems I've worked on. Not sure about the Nippondenso compressor but the priciples of a/c should be the same as it's really all about heat transfer which cause the different pressures and shouldn't be related to compressors. Doesn't sound like you are too far off, so you should be okay.

[Tim Hancock]

Thanks Tom, I was just going by some generic pressure/temp charts that came with my old gage instruction manual.

[Gene Alvarez]

I'm no expert, but with a thermometer (dial type) in the vent you should be able to tweak the refrigerant charge. I believe the air coming out of the vent on max should be around 40-45 F.