Uni-dock Dry camping pressure problem

Duke Orr · 05-07-2018, 08:16 PM

We recently bought a 2015 Eagle 339FLQS 5th wheel with the uni-dock valve system. When using the dry camping mode the pump seems to be pulling air in from somewhere, the pressure is poor, I can't purge the air and can't build enough pressure to cut out.

I disconnected the input (filter) side of the pump and connected a PEX line into a 5 gallon container, the pump works perfectly this way, builds pressure, cuts out etc.

I assume that this confirms the air is being introduced in the piping or valving. I plugged the city water connection using a hose fitting with a plug suspecting that the air was coming in via the one-way valve but this doesn't seem to improve the situation. Has anyone else had / solved this problem? I'm considering ordering a replacement inlet valve just to try. Thanks in advance for suggestions

Duke Orr · 05-22-2018, 08:37 PM

Anybody have any ideas? Help would be appreciated!

Sundancer330 · 05-22-2018, 08:49 PM

Sounds like the valve to suck antifreeze into the water system for winterizing is open and sucking air. Its usually near the water pump, has a valve with maybe an 18" clear hose that is open on the end.

Sundancer330 · 05-22-2018, 08:53 PM

Setup would look something like this, clear hose going up with valve should be closed

Duke Orr · 05-22-2018, 09:08 PM

Quote:

Originally Posted by Sundancer330

Setup would look something like this, clear hose going up with valve should be closed

Sundancer, thanks so much for your reply, unfortunately I have one a Nautilus uni-dock system that would be very convenient if it worked! I've had Jayco trailers with the winterizing tube but this one doesn't have the tube, winterizing is done by positioning the valves. The problem is exactly what would occur if that valve was open...I just discovered another thread that appears to be the same issue I'm having and I suspect that there is a cracked fitting that I haven't found (yet).

Duke Orr · 06-01-2018, 07:58 PM

So, in case anyone is following this,I removed the cover from the Nautilus uni-dock system by removing the mounting screws from the valves. Once the cover was off I could see that three of the connections had leaks when filling the tank. I figure that it stands to reason that if water can leak out when filling the tank, air can leak in when you're drawing from the tank.

I found the rubber seals for the fittings at the local RV store, less that 50 cents a piece and replaced the seals at the leaking fittings and..... I still have three leaking fittings. Focused on one of them, removed the threaded elbow that goes into the valve and also replaced the seal that was there (between the valve and the elbow) put it back together and....it still leaks. It looked like maybe the short piece of pex might have had a split. After a lot of effort I replaced that (had to use a dremel tool to cut the clamps, had to heat the pex with a torch to get it off the fittings, had a heck of a time to get the new clamps on due to limited space for the tool) and.... it still leaks. Pretty frustrating working on this especially with the mosquitoes feasting on me the whole time.

I'm going to tackle it again tomorrow but think maybe tearing out that valving assembly and going "old school" might be an easier and less frustrating approach.

Duke Orr · 06-06-2018, 05:13 PM

For the benefit of anyone following this thread, my problem turned out to be two threaded elbows that were cracked / split. You couldn't see the split with the naked eye but if spread the elbow slightly with the help of needle-nose pliers the split was evident. I wasted some time replacing the swivel seals (cone-shaped washers). It is worth mentioning that these seals are used at the swivel connection onto the threaded elbow but also there are two of these seals back to back on a plastic spacer between the threaded elbow and the valve. I suspect the previous owner didn't winterize the unit properly and the elbows split after freezing. There was evidence that someone tried to fix the leak by applying teflon tape to the threads on the elbow and either thought it was fixed or just gave up and put the cover back on...

Jethro · 09-22-2018, 04:55 AM

I'm a little late chiming in on this but its still important for others who have the same problem and read these threads later to know what the resolve was. Thanks to Duke Orr I was able to solve my water pressure problem as well. We had purchased a brand new 2017 Seismic 4113 and when we went to boondock with it the water pump would not build pressure as mentioned in earlier threads. Our issue also happened to be the same 90 degree elbow plastic fitting being cracked on the inlet side of the 12 volt pump at the back of the Nautilus P1 valve system (behind winterizing valve I believe). As Duke Orr mentioned it is very difficult to see and I also had to spread the fitting with a needle nose plier to see it. The funny thing is that it didn't leak when I was on city water so I didn't clue into it right away. I happened to notice mine by switching valves while on city water pressure and thats when it did spew out some water. Remembering Duke Orr's thread I removed the elbow and inspected it. I guess I didn't figure that a new fitting would be cracked like that, but it was. Now I make sure I carry an extra fitting and seals in our rig. Something worth mentioning here is that our dealer could not determine the problem after two visits. They wanted to swap out the entire Nautilus P1 valve system. All that for just one little elbow? Wow!

John from Central Florida · 09-22-2018, 05:05 AM

Jethro,
Even though I don’t have that system, this was a great, informative thread!

Jethro · 09-22-2018, 05:11 AM

Thanks John! Duke Orr was the one that helped me. We are all just trying to get by here.This forum has been a great source of info & help.

Rgrinker · 09-22-2018, 05:21 AM

I had a problem with my pump cycling once and awhile when my lever was on tank fill, when i moved it to city it stopped. Found Cracked elbow, mine was due to pressure on the elbow due to hose routing

Duke Orr · 09-22-2018, 06:50 AM

Quote:

Originally Posted by Jethro

Thanks John! Duke Orr was the one that helped me. We are all just trying to get by here.This forum has been a great source of info & help.

Thanks for the kind words Jethro, I get frustrated when I see posts where people have the same problem that I had but don't bother posting the solution. My thought is that it only took a few minutes to post the fix and, if it helps one person solve the same problem without going through the hassle I went through, it makes my day.

Glad I could help.

Cheers and happy camping!

Duke

Jethro · 09-24-2018, 04:19 AM

Your right Duke Orr. I feel the same way. If you didn't post your fix then I would still be trying to fix my plumbing problem. If I post my results relating to yours then it helps to verify the fine work you have done. What's really important is for other people to see is that there may be a common problem throughout many of our units that they can easily pinpoint on their own. I have been working on my Seismic over the past few months to resolve many problems that I have corrected thanks to these forums. Now I'm going back to many of those threads and posting my results in hopes that it helps others that are struggling thru their problems. Just good follow up.

Jus4fun · 10-16-2018, 10:03 AM

Hi Duke Orr,
Thanks for your post, I was dry camping this weekend and having the same issue as you, I changed out the water pump, no luck. Like yours it has a TON of air in it, this may cut down on my fix time !!

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