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Topic: What "size" back flow preventer (Read 506 times) previous topic - next topic

What "size" back flow preventer

I borrowed TulsaTrent's photo from an earlier post, I hope you don't mind Trent. I found it while doing a search for my problem.

My "back flow preventer" is not preventing the flow from going back. (I have a leak). Does anyone know off hand what size 1/2inch or 3/4 inch do I need to purchase? This is the fresh water intake behind the hose reel.
I'm guessing the moment I remove the old preventer the fresh water tank is going to empty through the hole. Do I need to dump the fresh water tank?

Thanks
Ed
Ed and Michele
2000 U295  36'  (Build #5600)
8.3 ISC 350HP.
2012 Jeep Grand Cherokee (Toad)
2001 Lance Truck Camper (Sold)
2001 Lazy Daze (Class C). RK Floor Plan (Sold)

Re: What "size" back flow preventer

Reply #1 –
Ed, unless your fresh water tank is under pressure or the  Water level is above the inlet.. shouldn't have water pour out.
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My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

Re: What "size" back flow preventer

Reply #2 –
Quote from: Lance Camper –
I borrowed TulsaTrent's photo from an earlier post, I hope you don't mind Trent. I found it while doing a search for my problem.

My "back flow preventer" is not preventing the flow from going back. (I have a leak). Does anyone know off hand what size 1/2inch or 3/4 inch do I need to purchase? This is the fresh water intake behind the hose reel.
I'm guessing the moment I remove the old preventer the fresh water tank is going to empty through the hole. Do I need to dump the fresh water tank?

Thanks
Ed

Ed, I would surely dump the fresh water to be safe. Then I would take the unit off and go to either Home Depot or Lowes to match up the unit to a new one. My preference is always Home Depot. The preventer will surely look different but you are matching up the ends of the new unit to what you have already.
Bob
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator

Re: What "size" back flow preventer

Reply #3 –
If your BF preventer is located in a always (easily) accessible location (i.e. not normally hidden behind a panel), you might consider substituting (or adding) a simple quarter-turn valve.  That is what I did when I could never get ours to stop dribbling water out the fill hose.  Open the valve, fill the tank, close the valve.  No more leaks.  Simple.

Photo:  Original BF preventer is partially visible behind black wood block at top of photo.  New white SharkBite valve is above the hose reel.
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"

Re: What "size" back flow preventer

Reply #4 –
Most of those devices are "el cheapo". If you replace them with "brand X", see if you have room to put unions on both ends, so it can be easily replaced. I know these things!  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: What "size" back flow preventer

Reply #5 –
It's 1/2 inch. Local Lowes only had 3/4 inch so it was back to FT to purchase. I dumped the fresh water tank to be safe. Used existing fittings to reattach. No more leak.

Chuck love your valve suggestion. Eliminate the BFP all together. I would do the mod in conjunction with a new fresh water fill.

Thanks all
Ed

Ed and Michele
2000 U295  36'  (Build #5600)
8.3 ISC 350HP.
2012 Jeep Grand Cherokee (Toad)
2001 Lance Truck Camper (Sold)
2001 Lazy Daze (Class C). RK Floor Plan (Sold)

Re: What "size" back flow preventer

Reply #6 –
When I went to buy my new replacement valve, before tearing into the wall, I had a choice of either male or female on the hidden coach side.  I bought one of each.  I used one of them on my 98, and Bill Chaplin needed and used the other one on his 93 U300, go figure.

I also always install a male plug to seal the valve whenever a hose is not hooked up.  I also bleed off coach pressure before removing the hose when disconnecting my hose.
Dave Cobb
Buckhorn Lake Resort The Club, #6202, Kerrville TX
check the map.  I do rent it out when I am traveling!
2001, U320, 36' #5887, in Kerrville, FT Club #17006, (7/23 to present)
2024 Jeep Grand Cherokee L, Summit, white
EX: 98 U295, 36' #5219, (mid door), (4/13-10/23)
EX: 93 U225, 36' (4/11 to 4/13)