jaylebon 10 Posted April 2, 2013 Hello everyone, Im currently having a bit of trouble with the heating in my C. Basically its an early corrado I think as its a 92. Its has the slide controls. Basically i can move all of the heater controls but the cold to hot one is very stiff when getting to hot. I am not getting freezing cold air but its barely luke warm when the car is up to temp. + only the right side of the car blowers work ? and would say its a pathetic attempt to blow air out as well. So im not sure if i have a matrix problem or just the vents are blocked? I have read a few known issues with the cables that link the heating controls but not sure how to tackle these issues. Is it a cable of the cables arent working properly and preventing heat and full control over the vents? any advise on what to check and what i need to do would be brilliant. cheers in advance Quote Share this post Link to post Share on other sites
P3rks 11 Posted April 2, 2013 I'm guessing all the vent flap foam has disintegrated; so now your flaps inside the heater box are full of holes, meaning air can't be directed any more. Plus all the disintergrated crap is making it difficult for the flaps to move. Plus the mechs have probably dried out and need a grease. Heater box out time I think. Enjoy! Quote Share this post Link to post Share on other sites
jaylebon 10 Posted April 2, 2013 That explains tough slider and re direction of air ? + poor heat? If so heater box . difficult to replace? dash off? cheers Quote Share this post Link to post Share on other sites
P3rks 11 Posted April 2, 2013 (edited) Yes. Pretty much. I've had to repair it on 4 of my old VW's of the same era. It's a heaterbox out job as you have to split it in two. Which is obviously a dash out job. Can be done in a day (or a weekend if you want to tidy some wiring up which I'm confident will need doing if it's not been touched before). Here is what I suspect you'll find: As you can see, the flaps are metal but full of large holes and if you look at the one towards the back you'll see the reminiscence of the foam which originally covered the flaps (and the holes) - Which is no longer there as it's all sat in the bottom of your heaterbox. Essentially when you pull the sliders those flaps operate like opening and closing doors which direct the air; not only to your feet, face or windscreen, but also the heater slider will bypass the heatermatrix or not. But since they are both full of holes the air always bypasses the heatermatrix, even when it's not meant to - hence why it never gets fully warm, or stays roughly the same temperature no matter what you do. So what I did was fully remove my heaterbox and split it in two (there are little metal clips and plastic tabs which fasten it together, it's easily split). Get some self adhesive heat reflective tape (Halfrauds, screw fix, B&Q - it's normally used for behind household radiators to reflect the heat). And simply cover the flaps: I then covered the edges with a standard household draft excluder. Once done: That's the flap for the heat by the way. The first picture is when the slider is at hot, second when cold. When in the hot position the hot air travels through the back of the heater box, over the heatermatrix, warms up and then to where ever you direct it. When in the cold position the air doesn't go over the heatermatrix at all so it's at a ambient temperature. So as you can imagine if the flaps got holes in it, moving the slider won't do much at all as the air will just take the easiest route. I'd also recommend cleaning the heaterbox out, greasing the mechanisms (the cables and also you'll see little plastic cogs on the underside of the heaterbox). And also replacing the heater matrix if you haven't done so already - they are a known weak spot. For info, pictures of the directional flap: And for the windscreen direction: First picture will go to your feet or the windscreen. Second to your face (where you can also see the heater flap which is set on warm) and the third controls the windscreen or feet (if it's open its windscreen, closed, feet). You can also just see the windscreen flap to the right of the flap in picture one and two. Hope this helps explain it. I really should do a how to guide at some point. Edited April 2, 2013 by P3rks Quote Share this post Link to post Share on other sites
dragon green 5 Posted April 2, 2013 Beaten to it ! Quote Share this post Link to post Share on other sites
jaylebon 10 Posted April 2, 2013 Brilliant post, thanks for the info. Not sure im confident enough for a dash off job but it may sound more difficult than it is. worth a shot? Much to go wrong? Quote Share this post Link to post Share on other sites
P3rks 11 Posted April 2, 2013 (edited) Brilliant post, thanks for the info. Not sure im confident enough for a dash off job but it may sound more difficult than it is. worth a shot? Much to go wrong? It's surprisingly easy. I can get mine off in about 20-30 minutes now. I think it's only 6 screws to take the actual dash out. First time round took me hours and hours because I was learning and being careful. Hardest thing is knowing what to remove, how to remove it and how not to break it. You pretty much have to strip the dash - Switches, clocks, steering wheel and cowling, vents, centre console, heater controls. Which is the time consuming bit. Then un-clip all the wiring loom as it's clipped to the dash. Then it's a few screws and the dash pulls out. It's very disconcerting first time you do it. Edited April 2, 2013 by P3rks Quote Share this post Link to post Share on other sites
jaylebon 10 Posted April 2, 2013 Why did they put large holes in the doors? save weight ? lol.. and put bad foam over it? Quote Share this post Link to post Share on other sites