Hey, all--I've read some threads re vent. woes, but still have questions, so... PO installed little lever-operated ball valves in heater in&out lines, so I assume the vertical rotary temp control no longer works. With both valves fully open, Def. and outer dash ball vents blow so hot I can't stand it. with valves half open, heat & Def are fine--nothing ever comes out of two center vents, no heat, no A/C. Nothing ever comes out of any lower vents, either.
A/C seems to blow cold when swithed on and ball valves closed, but only side vents.
As for push buttons, Off works. Def blows fan on full, plent of heat out of windshield and outer eyeball vents, not centers. BiLevel, LoAuto and HiAuto all seem to do the same thing--air but no fan(or maybe very low fan), heat or A/C from outer eyeball vents, not centers, not lower or floor vents.
Please come to my rescue! Grateful for all replies, Glassman

1984 300d Turbo 135k

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