dash air/heat flow

i have a problem with my dash air/heat switch the doors don't to let the air flow it has 3 diafram to open doors. one for top air one for bottom air flow and one defoster they look like they have little vacuum lines attached to them trace the lines back to switch but can't figure out where the vacuum is suppose to come from to operate the doors i can open the doors and direct the air by hand the motor home is a 1998 gulf stream disel pusher any help would be appreciated thanks
dash air/heat flow

You will most likely find your electric vacuum pump has either a blown fuse or is itself inoperable. They do fail. They are usually mounted outside in the front cavity area and typically feed a small round vacuum reservoir. Good Luck...

C Nash

Senior Member
dash air/heat flow

Welcome to the board Jerry. Find the vacuum reservoir Butch is talking about and see if you have vacuum to it. You will probably find that the vacuum hose to or from it has got a leak. Good luck