City water, fresh water tank cross connect

scaup

2017 T@B 320S- We seem to have a cross connect between the city water connection and the feed into the fresh water tank.

In answer to a previous question I had, one of the forum experts provided a diagram of the fresh water plumbing system. There is a one way valve located so that city water cannot flow into the fresh water tank.

What I am currently finding is that when I am connected to city water, water flows into the fresh water tank and eventually overfills the tank and water backs up out the exterior fill point at the side if the trailer. At first it seems like the city water connection is leaking but on closer inspection, water is coming out the fresh water fill tube. We also found that there was water on the floor inside the trailer.

Where is and how do I get access to this valve?

Any other idea on what might cause this?

By the way, we had a great 3 week trip around northern BC Canada. Just a hot or hotter than it had been here in Washington.

Thanks for any help or insights.

ScottG

I believe the valve is built into the pump. I think--but am not 100% certain--that replacing the entire pump is probably the most practical solution. I don't think it is very difficult, but hopefully someone with actual experience will chime in here.

The line through the pump is the only connection between the city water port/distribution side and the FW tank. If it's not getting in through the pump, than something supernatural is afoot!  :-0

SteveK

The valve is in the pump.  Before you replace the pump, be sure you are using a pressure reducer on the city water connection to the trailer.  Excessive water pressure can cause the pump to leak or damage the plumbing.  Secondly, turn off the city water, turn on the pump and run some water thru the faucet using the pump.  This can help reseat the valve in the pump.  Lastly, you should turn off the city water when you are away from the trailer for an extended period.  Plumbing problems can happen, and you don't want to come back to a trailer full of water.

Finally, if you still have an issue you can choose to occasionally turn off the city water and use the pump to use up water our of the tank or you can try replacing the pump.  The pump is fairly easy to get to and pretty easy to replace.

scaup

Thanks for your answers. I did some further research (probably should have done this first but....) by talking with the service department where I bought the T@B and with NuCamp.  They both agreed with the answers above. The one way valve between the city water connection and the fresh water tank is in the pump. The best solution is to replace the pump. Because the service department is really backed up and we need it fixed by 8/24, I will have to change the pump myself.

What the service department said is that this is a common problem they see all the time. They said that you should never turn on the pump when connected to city water. If you do it places a large amount of additional pressure on the one way valve in the pump and blows the valve out. If this true, maybe NuCamp should place a warning label above the switch for the pump. By the way, even with this valve blown out, the pump worked for pumping water from the fresh water tank.......although as I remember back, it did sound a little funky.

If anyone has changed a pump I would appreciate any suggestions. Talking with NuCamp, it seemed to be just reconnecting two water lines, the electrical connection and the connection holding the pump in place.

Yes, I have always used a pressure reducer for the city water connection. Do these ever go bad? Previously I had always placed the pressure reducer at the trailer connection but when I thought the leak was at the city water connection I wondered if the weight of the reducer and hose broke the connector. I have since moved the pressure reducer to the supply faucet but I wonder if even the weight of the hose might break that trailer connector.

Thanks again.

MuttonChops

scaup said:

. . . best solution is to replace the pump. Because the service department is really backed up and we need it fixed by 8/24, I will have to change the pump myself.

If anyone has changed a pump I would appreciate any suggestions. Talking with NuCamp, it seemed to be just reconnecting two water lines, the electrical connection and the connection holding the pump in place.

I've had mine out and even took it apart while camping.  As NuCamp has said it is a straight forward process.  Of course the working space is far from ideal.

Tips:
  - -  open the sink tap to reduce water pressure and the amount of leaking at the pump hoses.
  - -  work slowly, no fun dropping mounting screws.  If you do buying replacements may be easier

         than trying to recover the dropped one.
  - -  take before reference pictures for the wiring
  - -  tank input hose may drop down but generally stays within reach
  - -  Fine some way to hold the access door open . . . I used my head (not the best method)

Sharon_is_SAM

Thanks @scaup.  Good to know.  Regarding the pressure regulator, someone suggested that it is best to place that at the TaB as the hose water can get very hot, expand and increase delivery pressure.  Sounds plausible, so we practice that way.  Also, you want to place the filter at the faucet to prevent hose contamination.  Good luck with the pump change.

scaup

Thanks all for your comments and tips. I'll probably start the pump change tomorrow so I have a few weeks to ask for any additional help I might need.

Sharon_is_Sam- Good comment on the pressure regulator location. Maybe I should rig up a support under it to reduce the stress on the water connection fitting.....or is this just needless belt and suspenders? I had never thought about filtering the city water. What filter do you use?

Stay tuned......tomorrow I'll start a new thread on the fun and games we had with the battery and our new Zamp.

dsfdogs

@scaup you could attach a 90 degree brass elbow to the T@B and it helps alleviate the pressure from anything hanging off the inlet. I also put the hose through the front handle. My sequence is a bit different than Sharon though-I put the regulator on at the faucet, then filter, then Wye (if necessary), then hose, then 90* elbow. Good luck with your pump.

Verna

@dsfdogs, the reason we put the regulator at the T@B is because the hose can get warmed up by the sun or pavement, and it can create more pressure than you want. If you put the pressure regulator at the last connection, you get only the pressure you want. 

Sharon_is_SAM

@scaup,  Camco filters from Amazon or Walmart.  Use one a season, then discard.  I also spray the faucet with a 50% bleach solution before adding the filter.  One day you may run into a bad water supply, plus lots of people using those spigots.  I have as many vaccinations on board as possible, but I would rather not test my immunity.  I even use a filter when filling our jugs from a spigot away from the campsite.  Here are some devices that I have found helpful.  I have the elbow, but I have not used it.  OTOH, we routinely use the faucet connected to the city water inlet.  

gymcoachdon

I'm guessing the CSS has a much more favorable pump location than the S models.  It would be a breeze replacing my pump.  
As for the inlet for city water, I use a brass 90 degree at the T@B, with the filter attached to it, and the pressure regulator at the spigot.  I guess I do it backwards!  The 90 degree does a great job of reducing strain on the connection, in my opinion.  Hose contamination isn't a real problem, if you always have the filter at the outlet, and I'm a bit skeptical that heat could raise the pressure enough in the hose to cause a problem.  But it does sound plausible...time for a mythbusters episode!

Sharon_is_SAM

@gymcoachdon, we need someone in Arizona in August to test that theory!  Any volunteers?

scaup

Seems like if you do test the theory and if proves to be correct, you're in for a big repair bill. I plan to put the pressure reducer at the T@B and maybe support it with an adjustable pole type arrangement.

Sigh......one more thing to find room for.

Sharon_is_SAM

Check out that little faucet.  We hook up the regulator and hose under it and there is no stress.

kaylevine1

i also put my pressure regulator right at the faucet then the filter then hose then a quick connect-i take the quick connet apart and screw in the end then push the hose on-no twisted hose!! 

kaylevine1

our t@b 400 has outside shower