Mercedes: 190d blows hot air, mercedes benz 190d, number search results

Question
I have a 1984 190d that blows hot air through the defrost vents no matter what.  
Any ideas.  Thanks.

Answer
Answer:

#1. Broken vacuum line.
#2. Bad heater valve.


PART NUMBER SEARCH RESULTS WITH PRICES

Vehicle 1984 Mercedes Benz 190D 2.2
Part: Heater Valve
 Note:  Vacuum controlled.
R3020-20243 Heater Valve IN STOCK $30.10  
 
R3020-11893 Heater Valve Germany IN STOCK $21.56

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