Auto Electronics: chev astro, vacuum systems, spherical object

Question
The blower works fine but the inside vent doors do not redirect the air flow when switched from ac to heat or defrost.  It seems to be stuck on defrost all the time. Do you have to remove the dash to fix it.  Does it work off a vacume system or electric?  What do I need to do?


Answer
Bill, While this is not necessarily my area of expertise, most Astro vans work off vacuum systems. If your problem is a loss of vacuum, the first place to check is for a leaking vacuum reservoir. This is a softball sized spherical object, located under the hood, usually in the wheel well area. Sometimes they are hidden behind the inner wheel well panels. If you cannot find the reservoir, removing the panel to check for vacuum might be your best bet. Most control panels can be removed without removing the entire dash assembly. Good luck. Don.