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Topic: Vacuum switch for dash AC controls.  (Read 2641 times) previous topic - next topic

Re: Vacuum switch for dash AC controls.

Reply #25
I know this is an old post but I am also in need of Ranco vacuum switch which there are none.  Reading thru the posts I see in post 20 from Nancy S that she replaced with the Dorman 904-214 vacuum with build in switch.  Does anyone know if by installing this pump you them by pass the vacuum switch or any thoughts or help on how you would connect and wire.  Thanks
Howard & Rose
92 U225 GV - 36'  - Build # 3989
2003 Honda Civic
95 Jeep Wrangler
2018 Winnebago Travato 59K
4 Chihuahuas

Re: Vacuum switch for dash AC controls.

Reply #26
I'm not familiar with that pump but if you use a pump with a built in switch then there would be no need for the OEM one, just jump it out and you would be OK. Find out what the vacuum set points are on the pump first tho', on my 95 it takes about 6"hg to pull the damper from the defrost position to AC vents or floor. I have mine set to switch on at about 8" and off about 15".  Maintaining between these two set points have worked fine for our coach.  Yours may not need to pull that much. ??
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Vacuum switch for dash AC controls.

Reply #27
obsolete vacuum generator
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Vacuum switch for dash AC controls.

Reply #28

Just picked this up from Amazon for anyone looking for one of these. Shipping was UPS from Texas, it took 3 days to make it to me, not the 2 weeks Amazon is estimating.

Amazon.com: Ranco 9551N16V Vacuum Switch 12V 24V Automotive RV/Motorhome :...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

 

Re: Vacuum switch for dash AC controls.

Reply #29
Excellent discovery!  5 or 6 years ago, when this thread started, those vacuum switches were VERY hard to find.  I suppose either some shop somewhere is making reproductions, or someone found a stash of old original units.  Either way, if you have a early 90's model GV with one of these mounted on the firewall under the "hood", it wouldn't hurt to grab one for a spare.  See thread below for more info:

95 u280 Grandvilla mystery pump
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"