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Topic: Fresh water fill.One way valve? (Read 779 times) previous topic - next topic

Fresh water fill.One way valve?

Is there a one way valve on the fresh water fill besides the solenoid valve?

I am getting a little back pressure through the water hose and cant figure out where it is coming from..

Re: Fresh water fill.One way valve?

Reply #1 –
You may or may not have a fresh water inlet check valve.

I did a quick search of the Forum and found one reference to a 2002 coach which had a check valve "behind the panel for the aqua hot".  If you do have one, it may look similar to the item linked below:

Marshall Brass Check Valve Brass Backflow Prevent G-784 - RV Plus


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: Fresh water fill.One way valve?

Reply #2 –
Quote from: Chuck & Jeannie –
You may or may not have a fresh water inlet check valve.

I did a quick search of the Forum and found one reference to a 2002 coach which had a check valve "behind the panel for the aqua hot".  If you do have one, it may look similar to the item linked below:

Marshall Brass Check Valve Brass Backflow Prevent G-784 - RV Plus
If I do not have one (for discussion sake).. what would cause the water to back flow? fill solenoid? Just replaced it a month ago. Never had this issue before but as long as the fresh water is full it keep dripping.
Found this

Removing panel for water check valve

Re: Fresh water fill.One way valve?

Reply #3 –
Sorry - don't know enough about your water system.  It is more complicated than mine.  All I can suggest is a search of the Forum for the term "fresh water back flow preventer" or "fresh water inlet check valve" or something like that.  See if anything promising pops up.

I installed a 1/4 turn SharkBite plastic valve on my fresh water fill connection because even with a new back flow preventer valve I could never get it to stop leaking back through the hose reel.  In the photo below it is the white valve mounted directly 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: Fresh water fill.One way valve?

Reply #4 –
Think I got it.. wouldnt have found it without you  :))  ^.^d

For future references

Take off the grey fuzzy panel, look just to the left (on our coach) where the red and white water lines come from the other side of the coach, and there is a very nicely exposed and available brass check valve

fresh water check valve (back flow preventer), for Newbies

Re: Fresh water fill.One way valve?

Reply #5 –
I have the same issue with water leaking back thru the hose on hose reel. I keep a check valve screwed into the end of the hose
2000 U270 34' WTFE Build 5756 "Ole Red"
2014 Honda CRV
Washington, Vermont
Lady Lake, Fl,  Independence, VA
Former owner of 2002 U320, 2003 U320, 2005 U270

Re: Fresh water fill.One way valve?

Reply #6 –
I had an old garden hose that I used.  I cut it off, plugged it with a piece of dowel and caulk.  I keep it screwed into the hose when the hose is not in use. 

Also, after replacing the check valve three times, I started using a filter between the park water supply and the hose reel.  This has virtually eliminated the problem of tiny bits of grit which compromise the check valve. 
Jan & Richard Witt
1999 U-320  36ft WTFE
Build Number: 5478 Motorcade: 16599
2011 Jeep Wrangler Unlimited w/Air Force One
Jan: NO5U, Richard:KA5RIW
The selected media item is not currently available.

Re: Fresh water fill.One way valve?

Reply #7 –
Had the same issue. For weeks, I was taking everything apart thinking I had a leak in as line somewhere.  After checking virtually every line and fitting, I finally realized it was back flowing from the end of the hose.  Now I keep a simple male thread plug in the hose.......problem solved. 
Mark & Bev
2001 U295 36' Slide
Cummins ISC 8.3 350HP
Build #5802
Jeep Wrangler Toad

Re: Fresh water fill.One way valve?

Reply #8 –
I had water coming back out the fill hose and couldn't fine a check valve so I put a hose bib ball valve on the end of the hose
problem solved and because of this link I think I found the check valve but I don't think I will change it as it is hard to get at
and the ball valve works great.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Fresh water fill.One way valve?

Reply #9 –
Quote from: oldguy –
I had water coming back out the fill hose and couldn't fine a check valve so I put a hose bib ball valve on the end of the hose
problem solved and because of this link I think I found the check valve but I don't think I will change it as it is hard to get at
and the ball valve works great.

I have a garden hose 1/4 turn ball valve in mine and the only thing I need to keep in mind is that when the park water goes down I need to close that valve.  Otherwise I'm feeding the park from my 88 gallons.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Fresh water fill.One way valve?

Reply #10 –
Quote from: Old Toolmaker –
I have a garden hose 1/4 turn ball valve in mine and the only thing I need to keep in mind is that when the park water goes down I need to close that valve.  Otherwise I'm feeding the park from my 88 gallons.

No.  Actually if on shore water, water pump off, with the fill valve (between front seats on your coach) closed, if shore water goes off, you should loose nothing.

If check valve bad, you will only loose pressure in the lines at that time.

Yes, if on shore water AND pump on and check valve bad, you will loose 88 gallons.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Fresh water fill.One way valve?

Reply #11 –
Quote from: wolfe10 –
No.  Actually if on shore water, water pump off, with the fill valve (between front seats on your coach) closed, if shore water goes off, you should loose nothing.

If check valve bad, you will only loose pressure in the lines at that time.

Yes, if on shore water AND pump on and check valve bad, you will loose 88 gallons.

Aaaand the $64,000 question is:  Which switch do I reflexively touch if there is no water from the faucet?
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Fresh water fill.One way valve?

Reply #12 –
Quote from: Old Toolmaker –
Aaaand the $64,000 question is:  Which switch do I reflexively touch if there is no water from the faucet?
One would think, the water pump. I don't leave a hose hooked up except to fill.
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: Fresh water fill.One way valve?

Reply #13 –
In our '02U320, shortly after purchase (we were actually sitting in the parking lot at MOT and moving INTO the coach) we had an issue trying to get the water to fill properly.  They diagnosed a faulty water fill solenoid ... replaced it ... and eventually we got the tank filled and set off for a journey to Colorado.  Some while later, in Amarillo, we wanted to top off our tank.  Couldn't do it!!  Thus began a lengthy period of calls to MOT, FOT, and anyone else we could think of. Sometimes we could get a few gallons of water into the tank, other times it was a no-go.  Frustrated, headscratching, we camped in our son's town of Leadville ... where the mosquitoes are so huge and vicious that they can carry away small dogs and slow children ... and began searching for the check valve in the water line.  I was beating off the blood sucking insects and spraying repllant madly while Jeff was bloodying all his knuckles wrestling with the panels in the utility bay.  Nothing on that side!  I was talking to the very dear Mike Rodgers at MOT every day ... sometimes twice.  James Triana at FOT looked up the schematics for our coach and was not able to help us find any solution.  ACCIDENTALLY ... in desperation ... we pulled off the panel at the water manifold and found the check valve.  Easily replaced and problem solved.  So ... the solenoid was never the problem and we left extra $$$ at FOT for no reason, but that was the beginning of our calling that rig "The Problem Child".  Within 3 months we had all the problems sorted... and we loved it ... but the name stuck.
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Fresh water fill.One way valve?

Reply #14 –
Quote from: craneman –
One would think, the water pump. I don't leave a hose hooked up except to fill.
When I have the utilities, I stay hooked up.  Our U225 has better plumbing than the 1794 house in which I grew up.
Thinking ahead, when we go to Warm Springs, GA, that will be a Friday and Saturday night trip so I wont bother to hook everything up.  I can dump the tanks before we leave and dump when necessary when we return.

My Siata project?  I was going to drop the car onto its wheel this Sunday past.
Do you know how to make God laugh?  Tell her your plans.
Nasty chest cold.
But I'm going to visit the winter White House if it's the last thing I do.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.
 

Re: Fresh water fill.One way valve?

Reply #15 –
Quote from: Carol Savournin –
  ACCIDENTALLY ... in desperation ... we pulled off the panel at the water manifold and found the check valve.  Easily replaced and problem solved.  So ... the solenoid was never the problem and we left extra $$$ at FOT for no reason, but that was the beginning of our calling that rig "The Problem Child".  Within 3 months we had all the problems sorted... and we loved it ... but the name stuck.

On the U225, the check valve is right there at the water inlet.
But.
I've been playing Russian Roulette with the black water valve and yesterday the remains of the pull handle broke and I cut my finger.  Two new valves were on order for delivery tomorrow before I finished my tank chores.

Trouble shooting problems is a matter of knowledge, intuition and creativity.  Robert Heinlein wrote that the surest way to kill a fresh idea was to try and force it to the surface.  People working by the hour, by definition, can't take the time to think.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.