need a 993

How does one know that the air conditioner is in need of recharging?
What does the dealer or shop actually measure to make this determination?

Also, is this a DIY project or does equipment cost prohibit it from being accomplished at home?

TIA

Crimson Nape Racing

It can be a DIY project as long as all you need is more freon. An easy way to tell is to use a little thermometer to measure the temp of the air at the vent (55-60 degrees). Another way is to check the sightglass for bubbles while the compressor is on. The sightglass is on top of the dryer, but I don't remember where the dryer is (front left fender?). The right way to check is with gauges - you can get cheap ones from Harbor Freight ($50) or good ones for 3 times that. If you see bubbles, get a can of R134 with a hose from any auto parts store, find the low pressure connection on the compressor (I think the hose will only fit on the low pressure side) and charge till the bubbles go away. Make sure the condenser fan is running or you will overcharge the system.

Redblurr

Its always best to take it to a certified a/c guy. That way they will empty your system and refill it to the proper levels. A/C work is a bit tricky. Lots of factors. Those little DIY cans of refrigerent dont do a complete job most of the time. I see people all summer long who try themselves and end up coming in to have it done properly. Sure its a bit more money but in some hot climates it pays for itself fast. GL.

VNTGSPD

When I put my new A/C compressor on, I took it to a local shop that evacuated the system, then oiled and charged the system for $150. Works flawlessly and I know the pressures are right. I think I would have spent at least half that plus a couple of hours to try to do it myself.

Blaine S

When did Porsche stop using R12? Was it with the 993?

JM993

No, midway through 964 production (I believe 1993 was the first year of R134).

I do all of the A/C work on my cars myself. You need to invest in a good vacuum pump to evacuate the system and a good set of hoses/gauges to refill. It's not that hard.

Edward

IMHO, this is one of those things that is best left to a shop.

1. You don't do it often. I got my 993 in 01 and I've had to do it exactly once.
2. Any money you spend in equipment is recouped when?? ...when you do it again in what, 5 or more years from now?
3. It's not an expensive thing to get done when you compare it to the cost of good hoses/gauges required to DIY (yes, "good" equiop; cheap tools are always a bad idea, and in this case, deals with serious pressure) .
4. It is a high-pressure system that can cause injury to you if done improperly ...or damage the system.
5. Proper evac/recharge equip prevents the refrigerant from spewing into the atm ...I'm no "greenie" but I also don't pollute.

...My reasons, anyway, FWIW.

Edward

need a 993

Thanks for the responses everyone. Ok so it's best left to a shop.

But my other question is how does one know when it's time to get it checked? I just got my car earlier this year and don't know if the level of cooling is normal for a 993 or if I should be expecting more. Do you guys just get the system checked and charged every 5 years or wait until you feel the a/c is not working well?

lowblow

It seems to me that if the supply air is warm then you have an issue. The question becomes what is the issue? Is it a slow leak, and if so, where is the leak? If a recharge lasts for a substantial amount of time than its a no brainer, just recharge as necessary until which time the leak gets worse and the time between the recharges gets too short.

I am bringing my car to my independant this week because of "warm" a/c. I think the proper supply air temp should be somewhere around 55 degrees. I am worried that my problem will be worse than a re-charge, i.e bad evaporator, etc.

I see a large repair bill in my future, but then again I have had my car for 5 years and other than routine maintenance has not cost me much to own, (slippery slope not withstanding!).

mike

JM993

As a reference point, I bought a New high quality Robinaire dual stage vacuum pump for $200 and spent another $100 for New Robinaire gauges/hoses/adaptors. For those of us with multiple cars, this investment will pay for itself rather quickly.

As a bonus, nobody but me is touching my car

trojanman

As a frame of reference, my car's AC seemed to work okay up until earlier this year... I would notice that the cooling became less and less effective and I could hear my expansion valve opening and closing pretty regularly. I recharged myself three times over the period of six weeks or so and then finally came to the realization that I had a serious leak.

I did buy the R134 with dye in a futile effort (hope!) that I would find the leak in a somewhat accessible spot... no dice. I decided to do the evaporator replacement myself (I've posted on this in another thread), and found once I got to it that it definitely was the culprit (see pics below).

Anyway, that's my story and I'm sticking to it.

Randy M '96 Silver 993

Mine is in being worked on right now and I expect the same when he shows me the evaporator!

Well, at least I will be cold again! I had it recharged 2 times in about 6 weeks! Those damn slow leaks!!

Tango635

If you have to open up the system, it's a good idea to replace the dryer and the expansion valve. The function of the dryer is to absorb moisture in the refrigerent and to capture any wear debris from the compressor. If the dryer has been in long enough, debris can make it down stream to the expansion valve. The debris will clog up the expansion valve and not permit it to function (cool) as it normally should.

I'm with Jmarch, I too do my AC work. I got a Robinair vacuum pump and gauges. It's true you don't do it often enough to justify in terms of dollars, but then it also saves time. I hate going to shop to get onto their schedule then have to find a ride or make arrangements to get back home, then back to the shop to pick up, etc. That alone makes it worth it to me.

If you do decide to DIY, you may also want to make sure you have access to specifications and capacity for the AC system, i.e. shop manual, or search on this forum.

1pcarnut

Okay, I'm always looking for a good excuse to buy more tools, where is a good place to buy this Robiniare equipment?

trojanman

True... I replaced the dryer as well (much easier to get to than the evaporator). Although I didn't buy/rent a vacuum pump or manifolds. I'm paying ~$90 to have the system evacuated/recharged... seems like a deal to me.