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Best way to install a mono valve?
@lochlan , Baron, Find below a video link showing testing/removal/replacement of the heater control valve/mono valve in a 1990 W126 should be simsilar to your model and give you a good idea of what your in for. , Good luck. I hope this helped you out, if so let me know by pressing the helpful button. https://www.youtube.com/watch?v=PF3jmwCr…
