Don't let this happen to you! Blocked fresh water tank overflow with Nautilus system.

awahl

(Title altered for search purposes.)

We winterized our brand new Tab 400 in the middle of May due to some late season freezing temps, so- in preparation for our long awaited first trip - we got to do our first de-winterizing routine in early June. It went off without a hitch! We opened the low point drains to clear whatever antifreeze was in the plumbing, flipped our Nautilus valves to "City Water" and flushed the line. Easy-peasy! We switched to "Power-Fill" and put a few gallons of fresh water in the tank- and flushed the lines, then switched over to "Dry Camping" mode (all while leaving the Bypass on of course), and flushed the pump and the lines again... No problem. This was getting easy. 

With the hot water tank still on bypass- we got ready to sanitize using a bleach solution mixed in about a gallon of water (ratio of 1/4 cup bleach to 15 gallon of fresh). I put the Nautilus into "Sanitize" mode and added the solution to the fresh water tank -It worked wonderfully. The pump was already primed from the previous flush -so it "sucked real good"... I was stoked. Next on the list; fill the fresh-water tank, draw some bleach water through the lines, let it sit overnight, drain in the morning - we're ready to go camping...!  

I put the Nautilus back in Power-Fill mode, hooked up the hose, and turned on the water. I could hear the water flowing, and everything looking good outside, I went inside the trailer to watch the Fresh tank meter so I would know when to get back outside to turn off the water. Empty.... Empty.... 1/3 full... I stood there at the door and waited. 1/3 full.... 1/3 full... 1/3 full.. waiting.. waiting...  I heard a strange noise. "What was that?" Maybe the weight of the water tank filling was putting pressure on the floor or something - just a natural creaking sound....? 1/3 full... 1/3 full...  Something must be wrong... What is taking so long? (probably about 5-7 minutes have passed so far). I just happened to look down at the area between the fridge and the wardrobe... the floor looked, odd, right? Or, ...wait- Was the floor rising? 

IT WAS!! 

I ran to the water line at the house and shut off the water- then immediately called for my wife who was inside the house organizing things- "HONEY COME HERE QUICK...!" You know what I mean- like some of us do when something is wrong and we need to validate what we're seeing with our own eyes with our spouses -to make sure it's really happening...  She came and saw the same thing I was seeing- the floor in our trailer in the area above our fresh water tank was...not right. 

Have you guessed yet?

Our fresh water tank (bladder) was expanding like a balloon.  As water was being added - the air inside the tank had nowhere to go. The tank continued to read 1/3 full, because it was 1/3 full - with water. The floor in the area in front of the bed, and directly between the wardrobe and fridge was expanded (bloated really) perhaps as much as an inch or more - with a similar bloat showing on the bottom of the fresh-water tank. I imagined our tank puffed up like a big pillow.... I opened the fresh water drain, and yes; water (and don't forget concentrated bleach solution..) came rushing out.... No problem with these tanks holding pressure I can tell you! Anyway, we were pretty freaked out at this point. How could something so simple - and something being done for the first time- come this close to being a complete catastrophe? 

Know what this is?



It's the fresh water tank overflow/breather tube, located on the underside of trailer to the left of the Nautilus and behind the tire... You guessed it: a mud wasp, (or something else that does this kind of thing)- had sealed the damn overflow tube, and I do mean SEALED! - No air or water- or anything except little wasps were going to emerge from this hole without immediate intervention.  

It took us about 20 minutes to pick and poke all of the "larval stuff" out of the breather tube. We used a couple of long and then longer zip ties- to get as far as we could go. The corners were a bit tricky. We ultimately opened up the lower wardrobe area to get to the drain tube from the top...which really didn't seem to help -and I did not want to mess with the crimp on hose clamps used on all of the fittings (anyone know what those are called?)  



Finally- we got the tube cleaned out as best we could- and tried again to fill tank. My wife monitored the drain tube while I turned the water on- She swore she felt a puff of air...! I ran to the trailer and watched the fresh water indicator. Empty... Empty... 1/3 full.... 1/3 full.... getting nervous..... 2/3 full.... feeling relieved, the floor was not rising... yeah! I continued to watch all the way to full- and then, gloriously- water came spurting out of the overflow tube - HALLELUJAH!! We put water in our fresh tank without blowing up the trailer!!! 

I flushed out all of the lines to make sure we got all of the bleach solution out of the system- then emptied, and re-filled the fresh-tank again- twice...  We checked all of the hoses/plumbing wherever we had access and saw no leaks- I do not think the pressure made it into the lines particularly after I relieved it at the drain. The drains themselves appear fine. The floor while initially a little raised, after stepping around and "jumping without leaving the floor" - returned to what appears to be normal....We bought some stainless mesh drain covering to protect the area around the breather tube. And if you're wondering- yes, I had already bought and installed a stainless mesh cover for the Alde heat vent to protect that system against mud wasps and the like...  

For now, things appear okay,-and actually we just returned from that first trip yesterday and all systems appear to be fine but we will continue to monitor... Now that we're back we intend to let NuCamp know about this and see if they want to do anything (via the dealer or otherwise) to check things out... Curious what other owners thoughts are on that?   

There is probably more than one moral to this story, but please do check your fresh water tank breather tube for blockage before every fill-obviously. If you have a trailer with the Nautilus system - air MUST BE ABLE TO ESCAPE during fill cycles - it does not come out through the old style hose fill tube. I hope NuCamp or any manufacturer using the Nautilus system reads this and decides to put some protection on the breather tube. This should not be something any brand new trailer owner should have to experience. This should also be noted (in bold print) in the manual for both the trailer and the Nautilus system. 

Hope this helps you make sure this does not happen to you....! 

Awca12a

Thank you for posting this.  

I will add it to the next update of the unofficial manual

Bayliss

WOW, @awahl, you are darn lucky!!  Did you by chance take a photo of the plugged overflow tube?  I imagine that was the last thing on your mind at the time, but it would be good to have for warranty purposes in the event you discover any issues down the road.  At least you documented it here.  Good to know info for others to be aware of.

pthomas745

Its what you learn after you know it all that counts.

That is an amazing story.

Sharon_is_SAM

I will pass this on to John Sanate in nuCamp Customer Service.  Since that opening is not really obvious, maybe they can add a cover at the factory.  @awahl - can you take a picture of the covered opening and also the brand/supplier so that new owners can replicate your repair?  I assume this will impact 320 and 400 owners with the Nautilus.

TenTab

Can you post what mesh cover you purchased for the Alde vent and the overflow tube?  I have the Nautilus system as well and don't want to encounter this.

awahl

Hi All - Thanks for your comments today :-) I still get a pit in my stomach thinking about that whole experience... 

Regarding our plans for prevention... 

I have not installed it yet, but here is the screen for the overflow we plan on using... We purchased @ Home Depot- think it was in the faucet area versus the plumbing area... For installation I was thinking of either stapling it (with some heavy duty staples) or using 3 fairly short/flat head screws-  It is about 2-1/8 diameter... I am wondering if the mesh may be a little on the too tight side - but I can easily rinse any grime out before filling- and after all it is designed to let water through while blocking "stuff"- I do not recall the price but I think it was around $3.00... 



For our Alde heat vent cover - we're using this Camco product I found on Amazon here... (4.5" diameter) for about $10. 

It did not fit as a square, but almost perfectly fits as a diamond. I wired it on using the posts on the Alde and wrapping the wire through- It just made about 400 miles without budging. I will need to keep an eye on it in the winter to prevent ice blockage (can always remove in the winter).  



Thanks again for the comments! 

TNOutback

@awahl the flooring can take screws really well.  I might suggest some wide flange, course thread short screws, maybe at least 3 of them, to sink into the under side around the perimeter of your sink strainer, catching its edge under the screw head.  I used that exact same product to cover the emergency overflow pipe from the water heater in our house.  It didn’t quite fit over the pipe very well, so I put the strainer over the handle of a screw driver, and used a rubber mallet to reshape the screen to fit better over the pipe end.

Sharon_is_SAM

@awahl, was there nothing screwed on top of that opening?  I can’t fit my head around the picture of the inside drainage tube and that clogged opening.  Can you get a picture from the outside of how you accessed that area?

awahl

Sharon_is_SAM said:

@awahl, was there nothing screwed on top of that opening?  I can’t fit my head around the picture of the inside drainage tube and that clogged opening.  Can you get a picture from the outside of how you accessed that area?

...here you go @Sharon_is_SAM - this is a picture of the underside including the overflow tube (blue) on the left, and the bottom of the Nautilus (hole for the hose to come up through and the 2 low-point drains) on the right- The camera is just under and to the right of the driver side tire which you can see on the left. 

Sharon_is_SAM

Thanks @awahl.  Now I understand the hoses inside, too.

Verna

With my allergy to yellow jackets and wasps, I think I would create short hoses and cords that would just peek out of the “sleeve”, but would somehow have the ends protected from the weather and driving hazards. They would also have to be totally protected so those stinging carnitas couldn’t get into the Nautilus. 

The Nautilus is a great idea, but somehow the opening needs to retract so nothing can invade the opening. 

I need to think about how to have a self closing opening.....

TNOutback

@awahl, where are the low point/pressure relief valves for the Alde?

awahl

Hey Folks - here's the picture of the overflow tube strainer installed - I used 4 short lathe screws - seems to be on there pretty good. I think this is a good fit - will monitor and see how it holds up to the road, grime, etc...



@TNOutback - here's a shot of the two Alde water-heater low point drains... They are larger diameter clear tubes- I don't think the pesky critters like these so much.... but definitely will be keeping an eye on them....



Those two openings on the bottom left of the shot are the low point drains in the Nautilus compartment. The fittings are pretty close to the bottom of the tube- so I do not think the would make a good home for the mud wasps but will definitely keep an eye on them too.... Maybe one larger screen would work better than two small ones...

Cheers all! 

Arkansas_Gary

This recently happened to me.  If it happens to you then you must inspect the frame structure that holds the water tank up.  Although my plumbing held up the frame broke and now it is too dangerous to drive.  

pthomas745

@Arkansas_Gary sorry to hear this....can you tell us more about what broke? 

Arkansas_Gary

The subframe that holds the fresh water tank up.  It is both bent and broken from the tank inflating and bulging.   I’m betting many campers have this damage to a lesser degree.  If it looks like there is a bulge under the button better remove the shield and visually inspect.  I have pictures in my post.

Sharon_is_SAM

@pthomas745 - https://tab-rv.vanillacommunity.com/discussion/17790/tab400-freshwater-tank-repair#latest

RobInPA

Thanks for the great photos showing the screen install .. that's on my to-do list.  Your modification looks professional .. specifically, what type and length screws did you use?  

bjn2

I decided to make some preventive screens for my 2023 320s's drain/vent pipes. The drains for cold, hot, and fresh water all stick out through thick steel plate on our trailer, so I picked up a package of six sink strainers from Amazon and epoxied four thin rare earth magnets to the underside of each. 

Link to strainers https://www.amazon.com/gp/product/B0C59L883G/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Link to magnets
https://www.amazon.com/gp/product/B01NAL9I5H/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I used JB Weld epoxy to glue four magnets to each screen.



I put a dab of epoxy on top of each magnet, set the screen on the magnets, and then put a dab of epoxy on the screen above each magnet.



Here's how the screens look stuck over the hot and cold water drains on our 2023. I put another screen on the fresh water drain on the other side of the trailer. 

bjn2

There are two other vent or drain pipes at the back end of our 320s. They stick out straight down from the floor, so I crafted a different solution to screening them. I put two o-rings around the tube to provide some grip, and then secured a round piece of window screen to the tubes using a zip tie. I worry about the mesh clogging with mud, but that will be easy to inspect vs. having a cocoon inside the tubing. 

I should mention that we provide tube houses for mason bees, so we're quite familiar with tube nesting insects. The 1/2" pipe is too large for mason bees, but other insects might find the diameter just right.



Silicone o-rings - smaller than the pipe diameter for a snug fit.



Zip-tied window screen. Screen was cut into about a 4" circle. If you start your zip tie before you slide it over the screen, it's a lot easier to manage.



There's a white Pex tube with an angled cut exiting below the Alde compartment. The hose is the propane supply line. 

FreewheelinFranklin

This is all such great information. I'm most appreciative of the detailed photos folks provide of their various solutions to these and other problems. 

One of these days I'll have something useful to add, but having owned our T@B for 6 months I'm just absorbing all this great stuff now.