Mercedes Benz repair: why heat flows, mercedes benz 190e, number search results

Question
I have an 88 190e 2.3,why does heat flow from under dash when controls are off?

Answer
Best guess:
Bad heater valve, bad vacuum pods and/or broken vacuum lines.

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1988 Mercedes Benz 190E 2.3
Part: Heater Valve
 Note:  Vacuum controlled.
R3020-20243 Heater Valve IN STOCK $22.69  

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