absent dash heat

[DadD45]

Have 2004 Cross Country Coachmen DP....no dash heat AND the only air coming from control system is through the defrost vents.....any ideas for solution???

[DadD45]

Have 2004 Cross Country Coachmen DP....no dash heat AND the only air coming from control system is through the defrost vents.....any ideas for solution???

[Acker1]

You have a vacuum leak somewhere or a bad pump. Test your pump, hoses & vacuum reservoir.
The default position for those units is defrost.
DICK

[sparetire]

I'll bet your cruise control doesn't work either. Most use a vacuum diaphragm which is operated by the vacuum system as well. I can hear my vacuum pump run when I turn the key on to ignition without starting the engine. My vacuum motor is under the bed in the engine bay. It makes a sort of rattling/vibrating sound.

Happy travels,
Sparetire

[DadD45]

sparetire, cruise control works fine just no heat or controls......as before only air coming through the defrost vents and not heated no matter where the control is set...

[full-timer]

Yep.vacuum leak or loose hose,check and listen for leak.

Joe

[chasfm11]

Evans controls makes many of the dash units - perhaps yours, too. In mine, the vacuum pump was originally mounted in the engine compartment and that was too far away in hot weather so my dash always reverted to defrost, the "emergency" position. The knob on the dash is controlled by vacuum, too, and will not work if vacuum isn't present.

You should be able to hear the pump when you first turn on the ignition. If not, I'd start there. It only requires 12 volts and is easy to unplug and test with a separate 12 volt source. It could be a blown fuse. On mine, I bought some adapters and rigged a vacuum gage on a vacuum line feeding one of the switches under the dash. I wanted to see how much vacuum was actually present. That would be another good approach if you are sure that the pump works.

[jenks60]

I don't know if I can make this clickable, but will try. EVANS Click on your dash control. That is, if you have an evans.

[gerdathome]

I have had the same problem a while back. I found the solution in the rotary control switch in the dash. From the vacuum pump comes a little hose, I believe it was the black one. They look like a 14 gauge wire. From there the vacuum is distributed to the various position which will operate the vacuum controlled doors which in turn will give heat, defrost etc. In my case the little vacuum hose became disconnected at the rotary control and consequently was nuable to open or close the various vacuum doors according to your selection on the rotary dial.
I managed to shuve my disconnected hose back in its original location and then sealed ot with some silicon sealer in place. It works fine now.
Gerry

[sparetire]

If the Evans controls and parts do not look like the unit you have, another big provider of Class A dash systems is Acme Radiator and Air Conditioning, Inc. (not affilliated in any way with Wile E. Coyote or the Roadrunner!). My '94 Safari DP dash system is made by them and I had to buy a new heater valve from them. Nice folks to deal with and they didn't gouge me on the price at all. I went back to them and ordered all new dash vents; the old ones are like those in the 70's to mid-80's GM vehicles, they get loose and won't stay in position. Again, great price and help. Their site is: http://www.acmeair.com/acme_airconditioning.htm

Happy travels,
Sparetire

[J Walker]

I am fairly sure that there is more wrong than the vacuum control. You need the valve to open on the coolant line to get heat and mine is electrically controlled. I would check that out.

[DadD45]

okay, looks like ALL suggestions are in soooooo will test vac lines and check behind the control dial for "loose" items this weekend....will let you know outcome next Mon....thanx for the info..