01 base Boxster AC recharge questions

Hi Folks,
My friend's 01 (formerly mine) needs an AC recharge, and he's wondering what this entails:
Does it require any special Porsche tools for the various fittings? (In this case requiring it being done by a dealer.)
He could possibly bring it to my local shop (not Porsche specialists) that did the post-warranty oil changes, which implies their familiarity with getting to the top of the motor.
Are there any other consequences to consider for this service?
Thanks in advance,
Laz

The techs have described the process to me. Briefly, the A/C system is connected to a machine that pulls a vacuum in the system. The evacuates the system of refrigerant and some compressor oil. This stuff is captured. The vacuum is applied for some time. I think it used to be for 30 minutes but I seem to recall this has been upped to an hour now. If the system remains free of leak sign then the required amount of refrigerant is returned to the system along with the same amount of oil that was removed.

The engine is started and proper A/C operation is confirmed.

If your friend's A/C system is low on refrigerant there could very well be a leak in which case the vacuum will not hold sufficiently. The leak then will have to be found and addressed. Often the leak is spotted by the presence of a compressor oil stain but sometimes not. In this case the system is recharged and a dye is added that shows up under a black lamp. If the leak doesn't show up after a tech road test then the car will be returned to the owner with the request it be brought back after some usage so another check made of the source of the leak.

If say a condenser is found bad the system evacuated again and the bad condenser replaced, then the system checked for leaks and if ok refilled with refrigerant and some extra oil is added. There is a chart in the factory manual that gives the amount of oil that is "lost" when various components of the A/C system are replaced. This oil -- along with same amount of oil that is removed along with the refrigerant when the system was evacuated -- must be returned to the A/C system to ensure proper lubrication of the compressor.

From what I gathered and observed once connected and running the A/C system evacuator machine does not need to be monitored. The tech is free to work on another car so it is not like he has to stand by for the hour's time it takes to evacuate the system and hold the vacuum. He might make an occasional check to see if the system vacuum is ok or perhaps the machine -- as this might have gotten updated -- is smart enough to detect a leak and record this or alarm the tech or something.

Good points concerning leak checking procedure and coolant loss during parts replacement. As far as I can recall, and this was mentioned to my friend: there's yet to be a first recharge, so that's ≈14 years; plenty of time for something to've escaped, however slowly.

Does it require any special Porsche tools for the various fittings?
No special Porsche tools. Porsche's A/C system is just like any other modern A/C system running 134A refrigerant, where the high and low pressure ports are common for all manufacturers.

Are there any other consequences to consider for this service?
If the service is done correctly there should be no consequences.

But, having said that, the A/C system in a car is a sealed, closed loop.
If it is low on refrigerant there is a leak which needs to be addressed.
The procedure that Marc describes above is the correct one.

Generally the leaks are corrected by evacuating the system, replacing the leaky part and recharging.
But if the leak is small enough in a part that's costly to replace, many people opt to recharge periodically (once per year or such).
Keep in mind that when there is a leak in an A/C system, compressor oil escapes so just recharging refrigerant in the long run can cause damage to the compressor if it has lost enough oil which isn't replenished.

Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Quote
Laz
Good points concerning leak checking procedure and coolant loss during parts replacement. As far as I can recall, and this was mentioned to my friend: there's yet to be a first recharge, so that's ≈14 years; plenty of time for something to've escaped, however slowly.

There are differences of course, but my 2002 Boxster's A/C system has never had to be recharged. I have asked about this and the SM said that the times he has driven the car -- he drives it almost every time I have it serviced as he picks up the car and drops it off when the service is complete -- the A/C blows cold air pretty soon after the unit has been turned on. A few times I've asked a tech to when road testing the car for any issues to pass judgement on the A/C and so far no one has told me the A/C needs any attention.

Now I do use the system regularly to try to keep it in good health. A/C systems -- I've been told -- like to be used and often on these cars that is not the case, being of course roadsters and driven with the top down a lot; so maybe that has something to do with its lack of need of being recharged.

There is a chart -- in the factory manual -- that for a given ambient temperature shows what the A/C air temp should be when checked at the center dash vent with the A/C on max cool and the engine warmed up and IIRC at something a bit higher than idle speed.

If you want send me private email and I'l cut/paste this info into a PDF and send it to you. If your friend wants to check the A/C performance to see if perhaps the unit is in need of attention at least he'll have the how to.

Or he could just have it checked for leaks and if necessary the leaks addressed then the system recharged.