Replacing the center housing on the heater housing:

Now the heater box is out of the car you can start taking parts off so that the center housing can be removed from the box.

I bought a used panel for about 20 euro. A new panel will costs over 100 euro when bought from the dealer. The housing part is the same for the Behr heater and the Behr climate control. The dealer might tell you otherwise as they are listed under two different part numbers, but the panel has both numbers stamped on it.

For starters remove the two stepper motors for the mixing flap (the ones with the broken bracket) to make some room. After that remove the front housing part of the heaterbox. This panel is kept in place with metal clips. You can pry those off with a screw driver. Don't forget to remove the brackets that connect the housing to the metal frame in the car.

Pull away the outer gasket. You will see 4 screws. These buggers are the reason you have to take the heaterbox out of the car as they can't be reached with the housing in the car.

The center housing is fixed to the rest of the housing with the same metals clips thay hold the front panel and 8 screws. 4 you already seen under the gasket, and there are 4 more. To reach these you have top open the flaps on the panel.

Remove all four stepper motors from the panel (2 for the mixing flaps, 2 to open the center vent flaps) and rmove the clip holding the rod to the stepper motor that operated the defroseter vents. Now remove all small metal clips holding the center housing part to the rest of the housing.

Now you can pull the center housing upwards. If like me you didn't get a new seal to go around the heater pipes be carefull not to break it. Your unit should look something like this:

Remove all the gasket leftovers between the main housing and the two panels. Put the new gasket in place.

Rebuild the heaterbox with the new panel. And of course refiting is the reversal of removal ;)

Before refitting the heaterbox to the car it's a good idea to replace the o-rings of the aircon pipes that where separated.

Total amount of parts and cost:

BMW Part nr	Description	Price
64 11 1 374 325	Center housing ECC*	85.00
64 11 1 374 358	Gasket**	8.20
64 11 1 374 109	Gasket	3.08
64 50 8 390 602	Aircon O-ring	0.66
64 50 8 390 604	Aircon O-ring R12 pipes	0.87

You will also need some coolant to refill the heating system and lots and lots of tie wraps.

Prices are for Europe and are excluding all taxes.

*) The panel for the heater and climate control are identical. See previous note.
**) I got a used panel with the foam gasket still attached to the panel I didn't replace it.

Things I should've done, but am to cheap to do or forgot:

Replace the gasket around the heater pipes in the panel. part number: 64 11 1 374 369
Replcae the gasket between the heaterbox and the bulkhead: 64 11 1 374 357

Total amount of time:
About 1 weekend :)

Skills needed/difficulty level: The job looks harder than it is. You can do this yourself just take your time and remember where everything goes (take some notes and pictures if necessary).

Story by Johan735.