Fresh Water Tank Mysteriously Filling When Connected to City Water

HR_Taly

I've been quite spoiled for a while and have had the luxury of being connected to city water for the last few weeks.  I've just moved out to a new site and did my standard connection - camp water outlet to my white drinking water hose to my water filter to my brass pressure regulator to the T@B.

When I got back to my T@B after the first day, I noticed my fresh water tank was giving me a reading on the SeeLevel gauge.  Weird, I thought, but maybe because I had recently sanitised it with bleach and perhaps I wasn't level before.  So I drained it, and it read 0.

The next day it read over 30%.  What the heck, I thought!  But I didn't have time to deal with it.  Then it read over 70% and now? Nearly 100%.

I found one article back in 2017 about something similar happening, but that person wasn't using a pressure regulator, something I always have done. 

Anyone have any ideas on why this is happening and what I might be able to do to fix it myself?

Thanking you for any advice from a state of a bit of a panic!

Sharon_is_SAM

SeeLevel malfunction?  Malfunction of the pump backflow valve?  Have you actually confirmed that water is in the tank?

HR_Taly

@SAM yep, it's most definitely full.  It just hit 100% and I'm afraid what might happen (where the water might go!) if it's full and has nowhere else to go...  I'm very naughtily draining it onto the ground now.  It is just fresh water after all, but I'm not supposed to spill anything on my site.  At least it's only 11 gallons...

HR_Taly

Just found this (not for a T@B but...). Will peek around and see if I can find the check valve for the water pump.  http://www.forestriverforums.com/forums/f217/fresh-water-tank-filling-itself-when-connected-to-city-water-help-104655.html

Sharon_is_SAM

They recommended disconnecting the fresh water, then run the pump to see if the valve will reset itself.  Might have grit.  Try cleaning the pump filter, too.  

HR_Taly

Thanks, @SAM! I saw that too, and I'm going to try the disconnection of fresh water and running the pump tomorrow if I can get back to the T@B during daylight, thanks for the sense-check in thinking I should try it, too. 

Meanwhile, I was checking out that filter.  I think the entire thing comes out (not just the clear section that looks like it might twist off to clean).  Has anyone done this?  Here are two pages that seem to show it's one unit (possibly only replaceable, not cleanable?).  My T@B is a 2018 (purchased 7/2017) and it's the Shurflow 4008 water pump.

http://shurflo.com/rv-products/rv-accessories/rv-water-system-accessories/rv-strainers/112-twist-on-water-strainer-1-2-pipe-inlet

https://www.amazon.com/SHURFLO-255-313-Twist-Pipe-Strainer/dp/B000V2W0GE

dsfdogs

@HR_Taly, are you in the T@B Camping Trailers group on Facebook? I typed in "city water" in the search and a number of posts have come up with the same problem. I can't share, but here is a cut/paste from a guy that explains:
"Turn off city water, open a tap, run the pump a few seconds, shut off, repeat a couple times. leave pump off, turn city water back on. Use a pressure regulator if you are not.

Do you know what's causing this?

the one way valve is inside the front of the pump. it's just a rubber flap. high input pressure, running the pump while hooked to city water, gremlins.. can all cause the flap to curl a little on the edge, or otherwise, not seat correctly. Can usually, say 99.98% of the time, be reseated by doing the procedure above..

Here is a video.. it's an 8000 series pump, but they are all pretty much the same. When he points out "the O ring is already in place"... the rubber disc you see in the middle is the one way valve.

https://www.youtube.com/watch?v=6wsPiA09mXQManage

Shurflo Check Valve Repair Kit1

also.. if you fall into the .02% of pumps that won't reseat after doing the stop/start procedure, adding a inline check valve is cheaper then replacing the pump.. again.  possibly (probably) cheaper then just the repair kit for the pump too.."

Sharon_is_SAM

HR-Taly - yes that filter part can come out, but unless it is cracked or the sediment has turned to cement, you should be able to just unscrew the clear cup, rinse out the sediment and replace.  Keep an eye on that filter if you are somewhere (out west) where the water has a lot of minerals.  Not sure if it would collect there or not.

But, I think, dsfdogs has the answer to your tank fill problem.  Easy repair if you can’t reset the check valve.  Good post- I learned something.  Appears the Shurflow pump check valve does not always stand up to the rigors of continuous high pressure water.

HR_Taly

The good news is the water pump filter is very easy to remove, even if a bit awkward.  I'm glad I had put a bowl under it to catch any water as is slipped out of my hands at first! 

The filter was (surprisingly!) clear and clean.  It was also easy to reconnect.

I've cycled the water pump a few times and even just started using the fresh tank solely (to use up the water filling my tank) but when I reconnected everything... the fresh water tank still continues to fill.

Looks like the check valve in the Shurflo pump is bad. I've gone ahead and submitted a warranty claim on nuCamp's site.  Ah well.  The pump seems to get really good reviews.  I guess I just got a rare dud.

laetulos

Hmmm, have the same issue on my new Tab 400, plus the pump runs every 15 sec when turned on even without water being used.

TerryV6

Will bad things happen if you use the pump while connected to city water?  Or are you then just using water in the fresh tank, thus no harm no foul?  At the rally we were hooked up to water, but sometimes water pressure was so low.... We had water in our fresh tank of course. That was to flush the toilet.  Then pump was turned off...

Ratkity

@TerryV6, I'm not sure if running the pump while on city water will do anything except perhaps wearing it out more (shouldn't in the long run to be realistic). The old plumbing had the city water running through the pump and there is a check valve (mentioned above) that prevents water from going into the fresh water tank and also closes the city water port. If the check valve to the city side isn't closing the pump from fresh water and wouldn't prime and never get to pressure. The reason is the pump should never be run when no water is in it (dry). 

I wonder if some people who had pump priming problems really had a wonky check valve (keep in mind there was a SMALL bad batch of pumps between 2014-2015 - I would say all have been replaced... they went bad fast! Sister had one). 

Sorry for the rambling. I'm slightly decaffeinated!   

Sharon_is_SAM

Here is a screenshot of the plumbing diagram that ScottG created.  

I think the pump must have a one way check valve to prevent inflow from higher pressure city water (which sometimes fails, but can be reset) and the check valve at the city water connection prevents pumped water from coming out the city port.  So, @TerryV6, if you have city water pressure down-regulated to 50, the pump would be working against that pressure.  I agree with Ratkity, the pump would work harder.  But, if your supplied city water pressure is so low that you actually have better pressure with the pump, it seems like that would not add additional pump stress.  Terry, you were not alone - others did the same thing.  

Anybody know the pump delivery pressure?

jkjenn

laetulos said:

Hmmm, have the same issue on my new Tab 400, plus the pump runs every 15 sec when turned on even without water being used.

Is your Alde on, by any chance?

Ratkity

Keep in mind that 50 psi is the Max and the better regulators are set slightly below 50. The pump manual sometimes has the set pressure listed. There is a chance that the pump pressure is set higher than your city inlet regulator (or regulator is getting older). When the pump has a higher pressure set, it will shut off after reaching its pressure, thus seeming like you get better pressure if you run the pump on city water.

TerryV6

Second cup for me already...grin..    Just talking about thresh water tanks... It was interesting that in the Joe Mullet talk. He said that after draining the tank, there is still water in it.  They are working on designs that will change this, but so far...  To be clear, in a winterization scenario, this is not a problem.  They would like to get it down to a few quarts.  

(Comment:  I was much impressed with the man and his company)

Ratkity

Toy hauler leaves water inside AND I found out that the side of the trailer where the water inlet for the fresh water is on the side that rain fronts usually come from. When I opened the fresh water tank for flushing for winter, more water came out than I left it! Water was getting in the vent LOL. It's ok as it wasn't much. It was just a shock.

Verna

Here’s some info from üCamp18 to ponder. When we had low water pressure (always during my shower....), I turned the water pump on and it drew water from my fresh water tank. I checked the levels before and after the shower and the levels had gone down.

This was actually an advantage because I could still leave the city water hose connected, but I could chose to use my fresh water pump during times of more consumption. 

elbereth

@TerryV6, that worries me - just having standing water in there all summer long.  Seems like a great recipe for algae. Is there any way to completely empty the freshwater tank?

jkjenn

elbereth said:

@TerryV6, that worries me - just having standing water in there all summer long.  Seems like a great recipe for algae. Is there any way to completely empty the freshwater tank?

I empty my fresh water drain on the last leg of my trip so that it has the advantage of gravity as I go up and down hills  Of course, I live in one of the "hilliest" parts of the country.

ericnliz

@jkjenn, had to chuckle at that one! I do the same thing & it completely empties by the time I get to either the next stop, or home. Works like a charm. Just have to remember to close the valve before fillin' it up again!

Ratkity

I do the same thing. Just take out the plug (I don't have a valve) and let it drain out. For a little while, it drained so slow. Those darn plastic shavings! I got a drill pump and used my 20V Dewalt and yanked out the fresh water until all the bits seemed to come out and it was draining properly. It's also a great way to rapidly flush the fresh water tank when one has a 36 gal tank (the toy hauler).

I do flush the tank (and also run the pump, flush the potty and turn on the faucet and shower) between trips because I'm a weekender and also do a good flush before a trip fill-up. I camp in places that don't have water hookups. Keep in mind that I make coffee with water carried from the house and drink cold water I also bring from the house. I guess I brush my teeth in the tank water. It's not that I'm paranoid of drinking the water because it's in the tank. It's just that the house water is heavily chlorinated (for me) and I drink water I refill in carboys. I also use that water because I don't get scaling in the coffee maker from minerals.

That said, I filter the water coming from the house I put in the tank and if I have water hookups at the campsite. It's a seasonal filter. I just leave the filter on the hose. I think it can also reduce scaling in the hot water heater (although the anode says otherwise - I have a traditional hot water heater).

TerryV6

I guess I forgot to mention that we had added the water at the campsite as the water pressure was nil at times....   I also empty after a trip.  Jody disinfects from time to time... So don’t worry for me, my tank is as empty as I can make it.  I was just repeating a
comment made during the factory tour.  Someone asked Joe about water left in the tank, and he said current designs did not completely drain.  Joe’s words, not mine.  

(We have tried at home to fill and drain the tank to get an accurate measurement.  Me, I didn’t care, but I was ordered to help.  My wife, having spent close to 30 years in different hospital labs, had to measure input accurately, and then drain and measure.  Using the bal leveler and tongue jack, I tried to get it all out. Never quite did...)

Signed,
TerryV6 (no algae in my tank) 

TerryV6

And oh yes Verna, that answered my question.  

elbereth

Thanks, all!  I do leave the valve open on the way home (think I saw that here somewhere) and haven’t had problems yet, but I’m a weekender too so would rather spend my precious hours camping than trying to clean out the freshwater! 

BrianZ

Here's a little follow up on what I found that might help someone with check valve replacement part number, etc.
First, this page of shurflo pump specs has individual component part numbers..
It also shows the pressure levels for shut-off, restart, & bypass.


Also found this replacement part listing on amazon..
SHURFLO 94-800-03 Model 4008 Check Valve https://www.amazon.com/dp/B00XKZ31VC/ref=cm_sw_r_cp_apa_i_aaCxBb0906854
One of the reviewers stated this fixed the same problem he was having with fresh water tank filling from backflow of city water through the pump.
There may be other parts available that include more than just the valve.