Sticking Ventilator Control Knob

[shayes]

Has any Member found the Control knob for the heater ventilation settings, sticks and will not budge? On my W126 When the car is cold the knob turns in both directions easily. When hot however, I have found it sticks when moved from pointing to the windscreen/footwell, to the only footwell position. It gets no further than half way and won't budge in either direction and I am afraid to put too much foorce on it. Any ideas as to lubricant and access problems?

Thanks

 

[shayes]

Sticking Heater Control Knob W126 (corrected title)

Having difficulty with the control knob when hot. It sticks between Air vent to Screen/Footwell setting, and to just footwell, setting.
I have to have the Radio out one day and wonder if this will be the time to use some sort of oil on parts, if it just a mechanism problem rather than a more elaborate reason for the sticking?
Anyone, had the problem?

Stuart