94 vectra, in dash temperature controls when i change from a/c to heat to defrost will not change where it blows out from... just blows out defrost position no matter the setting.
Winnebago's and most other diesel pushers have a vacuum pump somewhere in the front where the wiper motor is. Either the vacuum pump is bad or one of the vacuum lines under the front hood of the rv. That is what controls the vents.
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Steve and Joy
2014 Itasca Suncruiser Where we are now