tank filler crossover from city water fill?

jbrosecity · 08-04-2020, 06:03 PM

Hope somebody has experienced this same thing and can offer me a quick solution. All of a sudden with city water connected to our 2019 Keystone Avalanche 382FL 5th Wheel, I am seeing water trickling out what appears to be the fresh water holding tank overflow port. This is located just near the water bay. I did not change any of the settings in the bay, this just started happening. See photos of all this.

I changed out my water filter because water pressure was getting low. I do have a pressure regulator inline before the water filter. All of a sudden water started coming out the overflow. This coach is not like others I have had where the tank fill and city water connection are one and the same - Keystone has totally separate hose connections for tank fill and city water. But somehow somewhere internally there does seem to be a crossover where water from city water is leaking into the tank filler and overflowing when it gets full. I tested this, by switching off the city water and running the water pump to draw down the water in the holding tank. This stopped the trickle coming from the overflow for a bit. But when I turned the city water back on, after a short time, the overflow trickle started again. Then I opened the low point drain on the FW tank and again within half a minute water stopped trickling out the overflow. So I have to find out how/why the water from the city water connection is leaking into the FW holding tank. Help?

**flybouy** · 08-04-2020, 06:09 PM

Most likely it's the water pump. Either the check valve has failed or there's some debris fouling it. Do yourself a favor and throw that "regulator" in the trash. It's not a true water regulator but only a flow restrictor. Get a good adjustable water regulator.

jbrosecity · 08-04-2020, 07:40 PM

thanks for the input. I have an adjustable brass rv water pressure regulator for our motorhome because we use it in many different RV parks. The 5th wheel is permanently stationed here and thepark pressure is not excessive the one I am using is a Valterra A01-1120VP Brass Water Regulator. Valterrra makes a lot of good RV parts and accessories and this one specifically says "IDEAL PRESSURE: Regulates water pressure to 40-50 psi to protect your RVs plumbing system. Ideal for older RVs "

When you says "Most likely it's the water pump. Either the check valve has failed or there's some debris fouling it." Does this pertain if the water pump is turned off? The crossover is happening only when on city water with water pump turned off. If so, what is the solution exactly? Can the water pump be removed and "cleaned" or do I just need to replace it? Shurflo pumps on amazon run $70-100, Not sure what brand I have... I have to crawl way back in the front underbay to access it. Anybody have a trick to possibly clear any fouling debris without actually removing the water pump and taking it apart?

thanks a lot

travelin texans · 08-04-2020, 08:19 PM

The "trick" is disconnect the city water & try running the pump for a day to clear possible debris, if that doesn't work it's the check valve in the pump which need repaired or replaced.
There's possibly a valve at the pump on the suction line from the fw tank that you could close when connected to city water, just remember if the pump is needed be sure to open that valve.
I also agree with Marshall, toss that so called "regulator", regardless of the brand or how well that brand performs, that thing "restricts" the flow regardless of the the incoming pressure which possibly accounts for the lower pressure you've mentioned. If the pressure where it's permanently parked is "not excessive" then remove that piece to possibly increase pressure a bit & improve flow.
IMHO it's best to install the regulator at the faucet end of the hose for 2 reasons, #1 if you use a real adjustable regulator it's too heavy to be hanging on the RV connection, which on most RVs is plastic, #2 if the incoming pressure is excessive the hose could rupture, not that the hose is of any concern, but the campground &/or your neighbors will appreciate not being flooded.

jbrosecity · 08-04-2020, 08:39 PM

good suggestions so far. I also found this post on the IRV forum from a few years back:
-----------------------

Your problem may not be the pump at all. If the pump doesn't cycle on its own when no city water is hooked up, the pump check valve is fine. If it blips occasionally, though, it is likely leaking. The other source of unwanted tank filling is the city water fill bypass valve, which is basically just a shut-off in a loop that bypasses the pump for filling the tank. If that valve leaks, the tank continues to fill whenever city water pressure is present.
-----------------------

Trouble is the poster did not go into how one replaces the 'city water fill bypass valve'. And I am not sure it is applicable with my Avalanche because as I mentioned before, the city water and the tank fill are actually two separate hose connections in the water bay. In my Tiffin motorhome, There was only one hose fitting and a valve in the water bay with two positions, city water and fill tank. The IRV post would make a lot of sense for the Tiffin setup, but I'm not sure it applies with two totally separate hose connections.

Right now I have the FW tank low point drain open so no water is coming out the overflow now... it's all draining out the bottom. We're on huge gravel lots here so allowing some water to run out on the gravel is no big deal here. Tomorrow, I'll shut off the low point drain and presumably over the next day or so the FW tank will fill up again from this checkvalve or bypass valve issue. Once full, I'll shut off city water and just use the water pump for a couple days as suggested by travelin texans. We do not ever drink or otherwise consume the well water here. We only drink and cook with bottled water. But my wife will do laundry on the water pump, dishes, showers etc. And I'll listen for any pump activity when not in use. And I'll see if that clears it. If not maybe I'll need to call a tech because I don't see how I would go about replacing any bypass valve idf there is one. I have replaced a water pump or two in my day and could probably manage that. Manual that came with the rig says I have a Pentair shurflo 4008 rv revolution bypass pump. It's an s.o.b. to access but if I were sure that was the issue, I'd probably attempt a replacement on that myself.

bobbecky · 08-04-2020, 09:12 PM

We had the problem with the internal check valve of the pump leaking water back into the fresh water tank several years ago, and where we were located did not have an RV dealer nearby. After I figured out why it was leaking, I went into the small town and found a hardware store where I purchased an inline check valve for the 1/2" PEX in our rig. I installed the check valve, initially on the tank side of the pump, but soon discovered that the fittings on that side were only designed for suction to pull water from the tank because water was leaking at the pump. I then relocated the check valve to the pressure side of the pump, and this resolved the problem. I have since replaced the pump for other reasons but left the check valve in place, as it doesn't cause any problems and works as a backup for the check valve in the pump. The check valve is the brass fitting in the lower center of the photo.

skids · 08-05-2020, 04:06 AM

If water is back-flowing through the pump, it will cycle on and off when no water from the fresh tank is being used and the city water is disconnected. Try to flush out the pump at full flow. Turn off city water. Open all faucets. Turn on pump and let ‘er rip. This should cause the valve(s) in the pump to open fully and with any luck it will flush out debris.

**flybouy** · 08-05-2020, 05:55 AM

" The 5th wheel is permanently stationed here and thepark pressure is not excessive the one I am using is a Valterra A01-1120VP Brass Water Regulator. Valterrra makes a lot of good RV parts and accessories and this one specifically says "IDEAL PRESSURE: Regulates water pressure to 40-50 psi to protect your RVs plumbing system. Ideal for older RVs ""

Nice advertising but it's still a flow restrictor. I'd challenge you to connect a water pressure gauge to the output side of that "piece of brass", turn on the water and come back in 10 min and see what the pressure looks like. If you want to trust it that's your choice.
Speaking of trust, I've been in more campgrounds than I can count where the water pressure is 40 psi or less during the weekend. Come Sunday afternoon when the majority of people leave the pressure will run up to 80 or even 100 psi. You can trust that to if you like. I turn the water off at the supply faucet if we're not within sight of the camper. More than once I've turned the water off to a neighbor's camper when they weren't' there and water was pouring out from under the camper.

Javi · 08-05-2020, 08:46 AM

This is a water pressure regulator that other thing is a flow restrictor

bobbecky · 08-05-2020, 10:16 AM

Attachment 29035I went through two different ones of those restrictors before I finally figured out that they weren't real regulators. I originally bought the Valterra adjustable regulator, but after less than two years, it started to fail, so I finally went to a plumbing supply store and bought a high end regulator, and the pressure never goes above the set pressure, and we've been in parks with it that have water pressure way above 100 psi, and they warn you that your plumbing will fail if you don't use a regulator. This is our setup, with a water heater flex hose going to the regulator and then the filter after it.

jbrosecity · 08-05-2020, 11:28 AM

ok, ok... since the consensus here seems to be that my Valterra regulator is a flow restrictore, despite their product description I switched it out for a Valterra Adjustable Water Regulator with Pressure Gauge... the one I normally use for traveling in my motorhome. Since pressures vary widely between campgrounds (I've seen 30 psi and I've seen 80 psi), I have always used this on my various rigs over the years to adjust pressure to around 45 psi or so. Since my 5th wheel stays in one place and the park water pressure is consistently about 50 psi, I figure the compact Valterra was adequate in case of a sudden spike. Contrary to cautionary posts, we don't get much fluctuation here... this RV Park is ALL full time residents who choose to live here by the lake as we do, so water use is pretty much the same any day of the week.

Anyhow switching out to the Valterra Adjustable Water Regulator set to 45 psi makes absolutely no difference in the pressure at the faucets in the coach. This was all kind of outside the thread here, but I appreciate everyone putting in their 2c.

The original question was about the FW tank overflow. As mentioned I noted it stopped trickling out when I shut off the city water. I switched over to water pump and didn't hear the pump cycling when all use inside the coach was off, so consensus seemed to be that it was likely NOT a faulty checkvalve, and maybe the water fill bypass valve. However, since this coach has two separate hose connections in the water bay for city water and tank fill, I'm not sure that makes sense either. Hard to know WHAT was going on, but rather than leave it trickling out the overflow constantly, I opened the FW tank low point drain. Within a moment or two it stopped dribbling out the overflow as the tank began to drain. It fully drained onto the gravel overnite, and this morning not a drip coming from the drain any more. Odd... so with city water still connected, it no longer seems to be sneaking by the checkvalve or bypass valve or whatever it was doing. Maybe some debris cleared as suggested. Who knows?

Anyhow it's been a learning experience... thanks to all who contributed. I'm just gonna leave the FW holding tank empty and open for the balance of the season until we shut down and winterize in November when we normally drain it. Then in the spring I'll add some bleach to sanitize and fill it up and see if we still have the overflow trickling.

m&m · 08-05-2020, 01:01 PM

Had the same problem with my 365mb. When I had to have the plastic filter replaced i the valve switch. The shop said they are designed to fail, had a recall on them. He instaled a new brass valve and the problem was fixed. you-yube has viedos on the valve. Part was $34. Short story.

jbrosecity · 08-05-2020, 05:58 PM

m&m - can you post that youtube link? It's hard to think how to search for the video

m&m · 08-06-2020, 12:17 PM

will go and try to find it.

m&m · 08-06-2020, 12:34 PM

There are several models. Go to Anderson Kantleak at You Tube. You will come with the different ones. I had a heck of a time trying to get the replacement cartridge.
If you google Anderson Kantleak water valve you can also find it. Amazon might still have the cartridge. Make "make sure you get the right number". If you find thats the problem and replace it lube it with FOOD grade lube. The gaskets are designed to break. I had 4 gaskets on the one cartidge, some have 3.

m&m · 08-06-2020, 12:40 PM

my Anderson Kantleak# was NANRV101-RF-4 Function . Brass about $200.00. Plastic about$60.00 Replacement cartridge $35.00. The plastiticwilll fail. Brass is the way to go.

ChuckS · 08-06-2020, 02:57 PM

Typical low cost RV water pressure regulator. The pic shows what your really getting...

A flow restrictor ....

CedarCreekWoody · 08-06-2020, 04:55 PM

Replacing that water restrictor/pressure guage won't help your problem but is a nice upgrade. The problem is a leaking backflow prevented in the water pump. You can often clear it by cycling on and off, alternating between city water and pump operation. Some people have opted to install a separate backflow preventer in front of the water pump.

Check out this discussion:
https://www.forestriverforums.com/fo...er-185095.html

jbrosecity · 08-06-2020, 07:37 PM

As I mentioned before... thanks to everyone for their input. I switched over to my adjustable water pressure regulator. Pressure is about the same inside the rig now as oit was with the Valterra non adjustable. I've always used the adjustable at various campsites, but started using this basic restrictor type here in our permanent site where the PArk water pressure is fairly consistent. But I have bowed to the pressure and will buy another adjustable for our traveling rig. Like I said, since I opened the low point drain on the FW tank, and drained it, no water seems to be slipping by at all now. It has dried up underneath the rig. I'll leave it open til winterizing and see what happens next year. Thanks again for the all the input

**JRTJH** · 08-07-2020, 04:42 AM

Opening the FW tank drain will empty the tank and prevent it from "filling to overflow" so the water seeping out of the overflow will stop, but that isn't "fixing the problem" it's "putting a band-aid on the problem"... The water is still "leaking into the tank" but, by opening the drain, that water is taking the path of least resistance and flowing out the bottom rather than the top of the tank.... Your leak is still there...

It's either the valving behind your convenience center or the diaphragm/rollers in the pump head...

Essentially, all you've done is "re-routed your leak".....

That said, one "preventative measure" that many people have adopted is to never turn the valves in the convenience center with water pressure on them. Doing that, tends to apply excess pressure to the O-rings, causing them to stretch and unseat, allowing a leak. The "other preventative measure" is to install an inlet screen (it's not a filter) on the water pump inlet line. That will "screen out any large debris" to prevent it from fouling the pump diaphragm/roller system.

When your RV was built, the FW tank was installed, then the fitting holes were drilled, glued/screwed into the tank. Drilling those holes allowed "drill shards" to drop into the tank and eventually, those small bits of plastic will be drawn up the water supply hose and into the pump head where they foul the diaphragm. The inlet screen prevents them from getting into the pump.

Our Cougar is 6 years old and every year, when I winterize, I find a tablespoon or more of plastic shards, sawdust and even sand/grit (probably from filling the tank with well water).

Those two "hints" may be all you need to do, once you get the problem resolved, which from the sounds of what you've done so far, is still "lurking in the FW tank.....

If you have a FloJet pump with the blue locking tabs, this is the inlet strainer you need: https://www.amazon.com/Flojet-017403...s%2C181&sr=8-3 It's one of the "best $9" you'll spend on your trailer water system. If your pump is a Shur Flo, there are similar models available for your pump.

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