Here's a riddle hopefully you guys can help me solve. my 500SE has never had heat from the main air vents since I had the car and I always suspected the monovalves (for some reason if I closed all the main vents I could get a decent flow of hot air through the small upper vents on the end. Between that and heated seats I never got cold enough to check it) I recently replaced the radiator and while I was at it I replaced both valves since the car is dual zone. Sure enough both old valves were completely destroyed so I figured it was solved however I still have no heat. The only thing I can think of is there is still a lot of air in the system since it was partially drained for the radiator and the valve box was empty by the time I pulled the lid off. Is there a way to bleed the system or could something more sinister be the cause?

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E30 B25
126.036
123.130 with 616-Frankenbenz (sold)
124.030-Greyhound (sold)
124.030-Schnauzer (sold)

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