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Hi Guys,

Ive recently had my Air Conditioning on my NA changed to accept the ozone friendly A/C gas but Ive got a few gripes.

1) The AC is just not COLD... I drove around on a few hot days and unfortunately the gust of wind when my car is in motion from outside is actually cooler than the air coming out of the AC vents.

2) There is a slight \"recoil\" feeling under the drivers seat when Im cruising in any gear when the AC \"switches on\"... Hard to explain, but when the AC is switched on, there's moments where it runs then sounds like its still on but not working to its full potential and then it charges back in with slightly cooler air - that is when I feel a slight recoil/crunch under my seat (No it ain't one of my farts either!)

Has anyone had any symptoms similar to the above when you changed your AC unit to accept the ozone friendly AC happy gas?

check if your condensor fan coming on in the engine bay when the aircon is on? ... did the guys check and find the leak before they retrofitted the system, and then checked for leaks after they had charged up the system?????? ....

but sadly sometimes when retro fitting the new refrigerant R134a in to the r12 system, the actull system design was never made for that type of refrigerant...so in effect it dosent cool as good, because the condensor (outside radiator style thing) size is wrong or the evaporator (under the dash) is wrong too. And therefore it cant reject enough heat out of the cabin to give you that cooling feeling.

It would be interesting to see if the condensor or evaporator from a NB model are diffrently sized to NA... and thats how they achive greater heat transfer... or then again maybe the compressor that is diffrently sized? Maybe someone would know the answer to this on the forum?

There are \"drop in\" replacement refrigerants other than having to go to R134a... one called SP34E and I think R413A... these are ment to be a close match but without the CFC's... but most if not all auto elecs just carry R134a and do retrofits.

Has anyone else had there systems retro fitted and its never been the same? or has it been better?


as for part 2 of your question? no idea!

my 89 NA6 just got done with a retrofit & new gas & it's been much better then before it got done (was running low on the old gas though). before got to a low of 13degrees out of the vents the guy said, & now a low of 6degrees

hope yours doesn't have a leak, if they did it properly they would have found out. when mine was done, they tested the systems pressure for an hour to make sure there was no leaks & leak tracing dye was also put in so if it did develop a leak they could trace it back by using a UV light or whatever it is.

the a/c is meant to be used for at least 10 minutes a fortnight to keep the compressor seals lubricated & conditioned otherwise they dry up & become crappy letting the gas leak out which equals an expensive bill for repair. luckily for me i did just that in the 2.5 years of ownership of the car & it kept working whenever i wanted it to (though, just not as cold as i thought it could be).

i had my 90 done recently too works much better. the compressors are sometimes the problem too as they are old . Usually they will dump the oil out of it ( give it probably its 1st service in 150,000 ks ) and hope for the best so it may even be the compressor.
do you have any better luck using the air con on recycle so its not working as hard ? like when it is cooling already cold air from insode the cockpit does it still suck?
is the shudder your talking about just when the compressor kicks on and off ?

I just had my aircon retrofitted and regassed with r134 today. The chilled air is now cold enough to numb my earlobes.