I have 2008 Voyage 32H on the Ford F53 Chassis. I have issues with the AC control shifting from normal to Max. I posted in the General Motor Home page but no one seems to know where I should look for the vacuum line or vacuum actuator. So the problem is the AC will only work on Max at idle. Any load to the engine and the airflow out of the vents stops. If I go to Normal the airflow resumes. Any help is appreciated.