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That air bladder under the couch

Before we took off last Friday I went to put 12# of air in the PVC air bladder under the couch. All I heard was the air bubbling in the fresh water tank up front. Where do I get a new one? FOT only? $$?
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: That air bladder under the couch

Reply #1 –
Most big box stores and plumbing supply stores.  They are also used on well pumps, so a common item, and maybe down the street from you.
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)

Re: That air bladder under the couch

Reply #2 –
Are you talking about the potable water system ACCUMULATOR?  If so, available at HD, Lowes, etc.

Pressure to 2 PSI below cut-in pressure for your pump. 23 PSI for the very common Shruflo pump.
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: That air bladder under the couch

Reply #3 –
Thanks Dave and Brett. It is mounted under the couch, looks to be made of mostly PVC, has a cap/valve on top for pressurizing the water system to 2# less than the Shurflo water pump.

I seem to remember Kent Speers posting something about the pressure bladder on his coach.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: That air bladder under the couch

Reply #4 –
Quote from: nitehawk –
Thanks Dave and Brett. It is mounted under the couch, looks to be made of mostly PVC, has a cap/valve on top for pressurizing the water system to 2# less than the Shurflo water pump.

Like these photos that Benjie posted?

Plumbing issues
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: That air bladder under the couch

Reply #5 –
My two have both been painted blue and metal tanks.  I have seen them at Home Depot and Lowes.  Interesting to see one made out of PVC.  The steel tanks have a rubber bladder that has air on one side and your drinking water on the other.  When you get water out of the air valve stem, you have a leak in the rubber and need to replace the tank.

I just upgraded to a new Shurflow 4048 pump that does not require a tank, we are still undecided if we like not having one to lessen the pump cycling.  The new pump is so quiet that we might just live with the running times.

As a note, it is easy to unscrew the tank, and screw in a plug to take the tank out of the system till you can replace the tank.
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)

Re: That air bladder under the couch

Reply #6 –
Without an  accumulator -expansion tank as part of your system ,watch the safety valve on your hot water tank .It may start to leak by from time to time.Gam
joseph gambaro
1999 U295 36'

Re: That air bladder under the couch

Reply #7 –
Gam,

Great point, that I missed when I read that the pump did not require the accumulator tank.  I had also read threads here on the forum of members using this pump, and removing the tank.  I will have to watch for a water tank valve (T&P) future leak.
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)

Re: That air bladder under the couch

Reply #8 –
The early grand villas did not have the air bladder system, only a plastic pipe under the coach which acted as an accumulator tank to keep the pipes from hammering  and was more of a cushion.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: That air bladder under the couch

Reply #9 –
My accumulator tank under the couch was white PVC (3") with a ninety degree elbow on the bottom for the 1/4" tubing, and a valve similar to the automotive air valves. I bought a new Shurflo Accumulator tank, installed it today. The Shurflo pump is a 4008 model, dated 2009.
I have to increase the pressure to 53#, two pounds under the 55 specified on the pump.

Out of curiosity I cut the bottom cap off the old tank just to see what was inside. NOTHING, ABSOLUTELY NOTHING!!
No sign of a rubber bladder, no place where one might have been. Weird.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: That air bladder under the couch

Reply #10 –
Norm, 53# sounds high. The accumulator "unloaded pressure" should be close to the "turn on" pressure for the pump rather than the maximum pressure of the pump.

Also, it sounds like the device on your coach was a hammer cushion and "pseudo accumulator" rather than a true accumulator. The air valve could serve the purposes purging for winterizing or introducing air into the hammer cushion in case it became too full of water to be effective. That would be consistent with air introduced into the "mystery pipe" bubbling up through the fresh water tank.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: That air bladder under the couch

Reply #11 –
Thanks Dave. The accumulator tank comes pre-pressurized at 30#. The 4008 pump has a label (clear and in great shape) with low pressure (cut-in) at 55# and cutoff pressure at 62#.
So, do I just leave the tank pressure alone now that it has been determined that we had an anti-hammer tank and not an accumulator tank? Because, obviously the bladder tank is now toast since I operated on it.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: That air bladder under the couch

Reply #12 –
Sounds like the 53 psi is appropriate for your pump. The accumulator will work at 30 psi, but I would expect it to work better at 53 psi. The pumps I have used have always had much lower cut-in pressures. I guess I'm just a low pressure guy. :P

If things work, call it fixed and enjoy!
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: That air bladder under the couch

Reply #13 –
I replaced my accumlator tank and FOT service personnel told me to pressurize it at 20#....I hear pressures from 10# to 50# so that is why I asked.
Steve Mudd
Commander, The Crystal Ship
CEO, Retirement Clearinghouse International
1993 Grand Villa U300 40', Detroit 6V92 Turbo
1997 Jeep Wrangler Sport
2008 Harley-Davidson Ultra Classic
2000 Harley-Davidson Wide Glide
swmudd@aol.com

Re: That air bladder under the couch

Reply #14 –
Steve, which pump do you have? Mine is a Shur-flo model #4008. The label reads 55# bottom pressure and 62 top pressure, so in order for this accumulator to do its thing it has to be set at 53#.
Do you have an accumulator tank or the anti-hammer PVC home-built unit probably made by FOT? It would be 3" white PVC with end caps, an air hose valve (like on your tires) on top, and a nylon elbow on the bottom connected with a 1/4" plastic line  to a tee right after the pump. Mine is mounted vertically to the inside front wall of the couch with a large galvanized pipe strap.
If you do have the PVC anti-hammer tank, leave it alone, add air periodically to purge it of water and save $53 by not buying the accumulator tank with the bladder.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: That air bladder under the couch

Reply #15 –
I have a blue colored acculumator tank mounted below my water heater.....I'm not that technical on these tanks and really do not understand why they are even needed, except to replace every now and then!
Steve Mudd
Commander, The Crystal Ship
CEO, Retirement Clearinghouse International
1993 Grand Villa U300 40', Detroit 6V92 Turbo
1997 Jeep Wrangler Sport
2008 Harley-Davidson Ultra Classic
2000 Harley-Davidson Wide Glide
swmudd@aol.com

Re: That air bladder under the couch

Reply #16 –
The blue accumulator or expansion tank is there for 3 reasons.1st it stores water under pump pressure ,and with the pump off injects the water back into the system to maintain system pressure so the pump doesn't cycle on and off as often.That helps the pump to last longer. 2nd It maintains a more uniform water flow between pump cycles. 3nd on a closed system when the hot water tank heats the water it expands and the system pressure will go up.It is possible for the pressure to go high enough to pop the safety valve on the hot water tank. Safety valves have a tendency to start  leaking by after they have been popped a few times. Your blue tank has a rubber diaphragm inside to keep the water and air from mixing. Some are just a vertically mounted tank with the top half filled with air. This type has to be drained or have pressurized air put into them from time to time because in use the air will be mixed with the water and leave the tank and it will become water logged and not work. Gam
joseph gambaro
1999 U295 36'

Re: That air bladder under the couch

Reply #17 –
Yup, what Gam said.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD
 

Re: That air bladder under the couch

Reply #18 –
Quote from: nitehawk –
Do you have an accumulator tank or the anti-hammer PVC home-built unit probably made by FOT? It would be 3" white PVC with end caps, an air hose valve (like on your tires) on top, and a nylon elbow on the bottom connected with a 1/4" plastic line  to a tee right after the pump. Mine is mounted vertically to the inside front wall of the couch with a large galvanized pipe strap.
If you do have the PVC anti-hammer tank, leave it alone, add air periodically to purge it of water and save $53 by not buying the accumulator tank with the bladder.

Norm,

I took a picture of what looks like a PVC anti-hammer tank as described in your post.  Dub is here from Arkansas in his "89 U280 and wanted to know what it was.  I thought it was a type of accumulator like the blue one I have.  He has no problems with it and I wasn't sure how much pressure there should be.  Thanks to your and Ron's (red tractor) posts we both know what it is!

Jerry

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Jerry and Cindy Maddux
1993 U300/36WTBI DD6v92TA
build 4271  "Miss Lou"
1995 suzuki sidekick 4x4 toad
Gulfport, Ms

"Pride of Ownership"