A/C and alternator question 82 300SD

[lwbdriver]

So I finally got my A/C charged and changed to 134. Air is nice and cold but for the life of me, I can't figure out how to open the middle vents without using the EC button (which lets in outside air). Cold air out the all 4 of the side vents and nothing from the middle. Normal?

Other question is now at low idle (with or without the A/C on), the alt light glows but goes out the instant I push the gas even like 1mm. Alternator on the way out? Thanks!!!

[sixto]

You make it sound like converting to R134a was an objective in and of itself. At best you settled for R134a

I don't know why the center vents work in EC but not in black arrow/white arrow mode. Seems to acquit the center vent pod in which case the PBU (push button unit) must be bad or at least need resoldering. There's a writeup on resoldering the PBU. Sometimes called CCU (climate control unit) but on early 126 ACC (automatic climate control) has a control unit outside the PBU.

Maybe the alternator is bad and you only need is a new regulator. Check that the regulator brushes aren't worn to the point of not making good contact.

Or your idle speed is too low.

Sixto
87 300D

[lwbdriver]

Thanks for the input. Yes, I settled for the conversion as a compromise. I'll have to figure out the vent thing and read over the write up. I really appreciate the help!