Mercedes: 83 SD Climate Control System, mercedes benz 300sd, climate control system

Question
Hi

When I engage the Air Conditioning, I get semi-cool air from the center vents, but the dash and/or the floor vents (depending which setting) blow hot hot air! It's bizzare.

I have a wrecked 84 SD as well (From which I harvested the 79K mile engine and transmission I currently use as well as endless other parts) and am hoping I can find the parts I need to fix this problem there. I was hoping you could help me cut off the hot air or even better, help me get cool air moving through all the vents!

Thanks for your time and and your help.


Luke


Answer
Answer:

Best guess:

#1. The mono valve diaphragm is bad.

#2. The mono valve coil is getting no power, 12V = full closed valve.


Monovalve Problems
http://www.mercedesshop.com/shopforum/showthread.php?p=1026761

Mercedes-Benz A/C Control Diagnostics
http://www.mercedesshop.com/Wikka/AcDiags

1984 300SD Climate control gremlins
http://www.mercedesshop.com/shopforum/showthread.php?t=149181


PART NUMBER SEARCH RESULTS WITH PRICES

Vehicle 1984 Mercedes Benz 300SD
Part: Mono Valve Repair Kit
 Note:  Heater Valve
Electromagnetic heater valve.     
R3023-15174 Mono Valve Repair Kit Bosch IN STOCK $44.59

http://catalog.worldpac.com/mercedesshop/sophio/quote.jsp?header=header.jsp&foot...