Is AC/Heater Vacuum or Electric?

[jamestouchstone]

Does anyone know if the 2003 American Revolution with a Cummins ISC 350 has a vacuum pump that operates the ac/heater controls?

[RangerSmith]

If it uses vacuum to change the controls then yes it has to have a vacuum pump as Diesel engines don't create vacuum.

[jamestouchstone]

I guess my question was not clear. I can't determine if the controls are vacuum or electric as nothing works so far as ac/heater /defrost/etc.

With just the key on, if engine is running everything seems to work fine, but I would like to know where the pump is, if it has one.

[dickandlois]

James,

The quickest way to check. If your Heater / Defroster defaults to the Defrost mode, then you have a vacuum operated system.

If the controls are not working, but the system is staying in the vent or heater mode, then its electrical operated.

My Fleetwood coach is a little older then yours and uses electrical servo motors to set the system modes.

A quick call to Fleetwood customer service with your FIN number will get you the answer and the location of the vacuum pump should your coach have one.

Rich.

[srfridley]

My 06 Winnebago (Freightliner chassis) uses a 12volt vacuum pump to run the heater/ defroster controls. It is located in the front of the coach in the generator access area, along with a small vacuum tank. You can hear the pump buzzing when the ignition is on and the heater is in any mode but off.

[jamestouchstone]

I will give Fleetwood a call as I cannot hear anything running with the key on & heater on.

I will investigate under the dash for electric servos.

Thanks for the input from all of you.

[jamestouchstone]

I did more investigating & found the heater/ac controls are all electrically operated.Thanks again for your input.