Anyone replace their HVAC assembly box?

Seen a lot of posts about fixing the HVAC blend doors (ie, the black foam problem) by going through the heat exchanger and/or cutting the vent behind the radio, but not much about anyone�s experience replacing the HVAC assembly by removing the dash. Curious if anyone has gone this route - whether doing it themselves or having a shop do it - and, if so, had any thoughts on it? While it certainly looks time consuming and tedious, but also seems (to my naive eye) like in the end its really just removing fasteners and prying clips (and thus not that hard). Sure I�m missing something so would welcome any thoughts the community has. Thanks!

Yes, a lot of people have done it this way. That's how Porsche will do it if you take it to them. I believe they actually replace the entire HVAC unit.

I have taken an entire dash out. Its not hard but there r a lot of fasteners to keep track and 25 year old plastic breaks.

You Tube

Thanks all for the responses! Sounds like a viable option. Appreciate it.

I have done it four times. It is tedious but not=t really hard. There are a lot of screws (approx 30) and a few are hard to see (Dash screws behind the airbag) and a few that are difficult to reinstall (around the rais sensor/at the center of the dash on top). Probably because they were installed prior to windshield installation. First time took all day but now it takes less than half that time. I did it on an interior swap (color Change) of interior on my wife’s blue 996 and have done it on the others to replace the foam on the blend doors. Removal of the HVAC box is easier than dash removal but it helps to have a second person on the reinstall. Meir Schwartz has a good write up on the removal but I found that you DO NOT need to remove the fusible link box between the HVAC box and the firewall to remove/replace the HVAC box. To remove the HVAC box, there ate two wire ties behind it that hold the main wiring harness and main cable to the starter motor. I had to cut the wire ties and then replace them. Good luck with it. Mark

I�ve replaced the blend door through the heater core access, then had to go back later and remove the dash to replace the AC evaporator core. Can concur the fasteners near the windshield are a pain and I dropped one into the defrost vent. Boo! You will save days and many opportunities to screw up just going through the heater core access.

@168Sierra - do you have a link to the writeup?

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Thanks, Mark. Very helpful.

I just had the entire a/c system replaced because of Black Death - new hvac box and servos, compressor, dryer, expansion valve, both evaporators and more ( the while you were in there idea) - imagine I could have done it if I had the time but let my shop do it - crazy expensive... at least finally had the leather dash repaired at the same time as it was out.

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Great video and he did all the work with one hand! My anxiety level goes through the roof when I watch these dash videos, thinking about tracking the parts and putting it all back together.

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Got it. Thanks. Yeah imagine a bunch of stuff in there worth replacing while everythings out. Assume independent shop or is this something a Porsche Center needs to do?

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Wow, sounds like a $5000+ job for a shop... Curious, were the condensers, evaporator, compressor, leaking freon..? What actually failed on the hvac system..? Whats do you mean by "black death"..? Black mold..? Or the black foam from the vent blend doors..?

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What is Black Death?

I cringe when I see the videos with guys demeraling the vents to fix the foam problem. Owned my 2000 C2 about 24 years now. Probably had the dash out 12 or 15 times for various reasons. Last year to fix the HVAC blowing foam problem. With disassembly, the most challenging area is/are the screws for the upper center vent. Be patient. The blower box on the bench ready for disassembly & repair. I used this stuff on the vent doors in the hope they'd provide a long term solution. If memory serves, I cleaned the two doors, put foil tape and then this stuff on top. Once you get the blower box back together make sure the two doors open and close smoothly. Play with the two arms on the bottom that are attached to the purple and green actuators to check motion. It does go back together. The most challenging part is probably adjusting the wires & trim around the steering wheel area. Again, be patient.

Black Death is when the compressor fails and send metal throughout the entire system. Cannot really flush out all the metal shards and any left in the system will destroy/ clog new compressor, expansion valve or just wait in hiding in evaporators until an inopportune time - and unless many/most parts are changed there is no warranty on the job because they know it will fail again..... pay once, cry once

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Great write up. Thank you!