How To Fix Blend Doors ~ Install a Heater Core and Reseal The HVAC Box

Published on February 9, 2018 under Video
How To Fix Blend Doors ~ Install a Heater Core and Reseal The HVAC Box

Blend door foam

If your MK3 or MK4 has no heat, no AC, or the controls don’t work, it may be due to the blend doors. From the factory the belt door is covered in foam to soften the door close, and divert air in the proper direction. Over time the foam breaks down and blows out the vents. Well it’s time to fix that. This is the most comprehensive guide to fixing blend doors out there.

Today I show you exactly how to disassemble the HVAC box, clean and recover all the doors, and reseal the box. All the products I used are listed below. There are plenty of other options out there,  but most of these items can be found easily online, or at your local Home Depot Motorsports.

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Products I used in this video

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  1. Winborn Gregory

    Great video. I actually did this same job on an ’00 New Beetle as part of my lab exercise at school. Every student had to remove a dash. I did not use any foam and it worked okay. Like yours better. I just wonder why you didn’t go ahead and replace the evaporator coil. Hope you don’t regret it some day. This is not a trivial job. Bet you never did one of these at the dealer job – not a money maker.

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