Cab air vents not working

[BadgerBob123]

Defrost and floor vents working but not face vents

[Morich]

You've given hardly any info to get down to actual facts but , generally I would guess one or more of the tubes which feeds those has dropped off.
Or it could be the controls have failed????

[BadgerBob123]

When I turn on vents or ac no air blows out but the fan is working.

[Fotoguzzi]

What vehicle are you talking about? It's hard to give an answer without more info.. maybe the blend door solenoid has failed?

[BadgerBob123]

2015 Winnebago Vista 27n

[Fotoguzzi]

Here's one place to start if it's the blend door, put this into a google search,
vista 27n air conditioning vents not working

Or look here, I know you don't have an f150,

https://www.f150ecoboost.net/threads...h-vents.78064/

[BadgerBob123]

Thanks I’ll check it out

[Bones2003]

BadgerBob, according to the Winnebago parts diagrams, the 2015 Vista 27N has vacuum driven actuators that control the blend doors (or dampers) in the air distribution box. Frequently there is trouble with the vacuum lines either splitting from age or getting chewed by rodents. Also the vacuum lines may have rubber couplers that connect to the actuators and those couplers can deteriorate over time. The vacuum hoses or lines are the tubes that Morich is talking about in post #2 above.

It is less common for the actuator to fail and even less common for the control unit on the dash to fail although either one could have failed. If you have not used the 3-D parts viewer on the Winnebago website, I suggest you try it out. It is under the helpful links under the owners tab. Using that viewer you can spot exactly where the vacuum actuators are located inside your dash.

[Bones2003]

BadgerBob, looking at the Winnebago drawings a little closer shows that the air plenum is located right behind the center console on your dash so you will have to remove that to gain access. With the radio and all the controls on that center console it is a real pain to remove it. There is a vacuum actuator (also called a vacuum motor) on the driver's side of the plenum that controls floor/defrost. There is a second vacuum motor on the bottom of the unit that controls the damper to the dash vents. From the description of your problem symptoms, the one on the bottom is the one you need to focus on.

[BadgerBob123]

Thank you very for the info I really appreciate that.

[NeilV]

Originally Posted by BadgerBob123

Defrost and floor vents working but not face vents

When there is a vacuum leak in the system it will go into limp mode defaulting mostly to defrost to keep the windshield clear. Often the problem will be the thin colored hard plastic emissions tubing used to provide vacuum to the various components in the system which are extruded and tend to fail along the length of the tubing at the seam. You can get plain black plastic emissions tubing at most parts stores to replace just the sections that have failed using short sections of rubber tubing as splices. Another common point of failure is the where the connections are made to the vacuum reservoir tanks which may be hidden in the frame rails going across the front of the coach. These may also be just short sections of rubber tubing used to connect the hard plastic tubes to the ports on the reservoir tanks which may look like black plastic bricks.

As the coaches from the year 2000 ish on start to age this brightly colored tubing has become a very common point of failure with the main symptom being the dash AC going into limp mode providing mainly air flow to the defroster.

[BadgerBob123]

Thank you for the information

[Geosman]

Yes, if you winterize and store it outside watch that engine compartment closely. I had to use Decon in the engine compartment when in outdoor storage. Squirrels ate vacuum lines, foam gaskets between the AC/heater box and dash as well as injector wire insulation. Talk about headaches making repairs. Now I pay extra for an all enclosed storage area but still keep the Decon box set out just incase I get some unwanted visitors.

[BadgerBob123]

We don’t store it for the winter we’re snowbirds in Arizona