kylejohnston1

Took my 964 into a local Porsche indy shop for an a/c service. The shop has been around for over 30 years and seems to have an excellent reputation. I'm not very knowledgeable when it comes to a/c so I am just trying to do my homework...

The quote was $2561 to replace the evaporator core, expansion valve and dryer bottle.

They also recommended using Freeze 12 instead of converting to R134a and said it would cost more and probably not cool as well if I wanted to do the 134a conversion.

What is everyones take on the price I was quoted and the comments regarding Freeze 12 vs 134a? Thanks in advance for any suggestions or input...

Kyle

911Jetta

I'm not an AC expert but recently had my system converted to R134a...

I've had the car for 3+ years and in that time my AC has slowly lost its ability to cool, so I was faced with either finding R12 or converting to R134a? I was worried it would cost $$$$$$.

I took it to a shop that services German cars, but in no way specializes in Porsches...they found no major leaks or problems in the system and started the conversion. The R12 to R143a conversion took over 1 1/2 hrs. - to suck everything out, test pressure, etc.). New fitting were put on and I was on my way for $113.

It's been three weeks since and I'm still blowing ice cubes.

J richard

Price sounds a little steep, but its a crapload of work to get at the evaporator coil, the core itself last I looked was about $600 and I think its close to 10hrs of work to do it all. not a fun job. As far as the 134, it is not as efficient as r12 but it will work, but it will slowly leach through R12 hoses, you need barrier hoses to keep it in, you can keep filling it back up if you have a cheap place to get it done, but I'd just go the Fz12 route.

-nick

I would go with the upgraded Griffiths evaporator & expansion valve if you're going to do it.

Not sure about using Freeze12, but I've heard from lots of sources that the 964 R12 systems use all the same components as the R134a systems. So there shouldn't be a need to change hoses if you change to r134a.

Jon A.

What exactly is wrong, and how did they diagnose the problem?

Metal Guru

If you study the vent temp vs ambient temps graphs for R-12 vs R-134a, you would find that R-134a is a little more efficient than R-12, especially at 80-90 degree F ambient. It would be my choice for a recharge instead of Freeze 12.

J richard

Been there done that.....

I would recommend swapping out for Griffiths equipment better and cheaper, it is a crapshoot if you have the barrier hoses on the earlier car, if it was a 91 on no problem. The evaporator coil is a common failure point on the 964 due to the condensate drain getting clogged up with dust and pooling condensate in the drainpan, the coil is aluminum it sits in the pan and basically corrodes away, a good reason to make sure you drain is clean...

The 134 is about 30% less effective in transmitting heat than R12, so systems designed for it have larger coils and use a higher system pressure, it will work but will not be quite as cold as r12...don't get me wrong its great to get cheap top offs, but nothings free...

here's the parts:


http://www.griffiths.com/shop/index....roducts_id=188

http://www.griffiths.com/shop/index....roducts_id=187

http://www.griffiths.com/shop/index....products_id=60

Metal Guru

So if you have actually looked at and understand the graphs how can you say R-134a is less efficient than R-12 if it removes more heat than R-12?

kylejohnston1

Didn't mean to start a refrigerant debate here.

It's a MY91 so hopefully the barrier hose should be fine. My a/c hadn't worked since I bought the car. The shop added some refrigerant and said the compressor is working fine but the evaporator was leaking. I've got a call in to the shop to ask about the possibility of using Griffiths equipment. I had budgeted around $2000 (hoping for less of course) to have the a/c fixed so the $2561 figure is definitely pushing it. I may have to tell them that I'll pay for their time thus far and do the actual work myself if there is a possibility that any other costs could arise.

J richard

Kyle it is a lot of work to get to the core, but if your handy...

no worries the chart looks pretty clear to me:

BHMav8r

It was about $1000 to replace my core - ater seeing what they had to remove to get to it in the 98 degree shop, I gladly paid it.

kylejohnston1

BHMav8r, I'm guessing the $1000 was for labor only, right? Did you end up going with Griffiths or oem parts and do you happen to remember what the parts tab was?

J Richard, thanks for the chart should I ever need research when velcro shoes are acceptable...

kylejohnston1

Just picked the car up tonight and enjoyed cold a/c in the Houston heat for the first time since I've owned it!

Total cost ended up being $2200 which I am okay with as long as it lasts for a while (fingers crossed)...

Makmov

I have mine almost working now....

It didn't work when I bought it but some was spending money on to get working just before I got it. Looks like they replace the compressor clutch, the condensor fan, and a $400 hose, only they buggered up the hose putting it in. So I replace the hose and it still had a leak, a little brass plug in the back of the dryer with a hole in it filled with lead was leaking. I am sure whoever was working on thought it was the hose. That is what I thought it was too.

So I replace the hose the correct way. Some moron short cut it the first time and like why it was screwed up.

Finally I got it to take a charge, compressor works everything was going well.

The condensor fan worked for about three minutes.

So as long as it's moving it blows cubes, but if I sit at a light or stop it stops blowing cold, which I am sure is because the condensor fan is not working.

I traced the fault back to the ballast resistor, which had completely fallen apart to the point a wire fell off.

Of course it's in some retarded place to get to.

So as soon as I get my part installed my system should be working 100%.

I am sure it would have been well over $2000 if the dealer did it, but I did it myself and am into it for about $400, including buying a set of AC manifold gauges and a ballasit resistor that I ordred.

I was going to use R-12 but you have to have a license and the refrigerant alone is about $130 vs about $35 for 134a.

It's been about five days now and it hasn't lost any of it's charge so at least there is no more leaking issues - so it seems.