2018 Era 70A - No pressure in galley cold water line

[N1ven]

Frustratingly, I have no water pressure in the line that leads to the input for the Culligan cold water filter. I replaced the whole filter unit thinking it was plugged or defective but the water line has no pressure on either city water or with pump running. So, no cold, filtered water to the galley sink. Cold water works great in shower and bath sink. Traced the blue hose back to the back of the rig looking for a valve but couldn't find the end up by the pump or in the very back. What could possibly be wrong? I reviewed winterizing info carefully and had a 33' Voyage for 16 years. Traded to Winnebago dealer but not nearby. Hoping the community can help!

[Morich]

Good time to mention the online parts catalog as it lets us look at lots of those things hidden in the walls!
https://catalog3d.winnebagoind.com/menu/Parts.htm
A great site as it is interactive and seems to be very accurate! Amazing thing to have when we want to look at plumbing!

However it does take a bit of learning/practice for most to get good use, so if you will tell us a bit more about the RV, I'm game to try to sort the question a bit further!

first thing when we look for the drawings is that your RV had two builds, early year and later. Early has a 7th digit of 1 in the serial number (not VIN!) and a 2 for later build.
you may know about the label next to the driver that has lots of that info?
Can you tell us if the RV has a build date before 7-30-2017 or after?
That would let us go direct to the plumbing drawings with more confidence that we are the right place!
As a quick question, am I reading correctly and you took the water line off the filter and found no water, correct? All other water seems okay, just not this one faucet and on cold? Hot water at this faucet okay?
Not something as simple as the aerator on one faucet stopped up after storage?

One faucet that is on the same line on one version of your Rv, is the exterior faucet outside in back, if you can check that one without a lot of trouble?

[N1ven]

It is a "1" so early build. Yes, correct, all other lines hot and cold are pressurized, just not the line that runs through the filter to the sink cold side. I will get out there Friday and check the outside water line on the very back left side. That must be where the blue hose disappears to behind the bed after it crosses over right to left side.

[Morich]

Quick thought but possibly not the right drawing?
Is it possible the valve to suck antifreeze from jugs is left rather than put back to the normal feed?

Click this snip for best view!


Blue line might be normal flow but red line can't flow from suction hose if cap is on!
Line going off screen to left under the filter feeds only the exterior faucet, so if those two are dead, the valve setting is suspect!

But that may be the wrong drawing!!!
guessing gets me in trouble!

[N1ven]

It is NOT on Winterize, it's on the other setting (Normal or whatever).

[N1ven]

Yeah, I'm sure the exterior faucet will also not work because it's on the dead blue hose. I'll check again on Friday, but the valve is definitely turned to Normal. I cycled it back and forth. The end of the hose (that you drew with red) on the right is an open female hose fitting. Not capped but as the suction line that would be OK if the valve is closed. I would think it would pump water out of the open end if it were on Winterize. I do not see where water, either from the tank or the city line, ever hooks up to the blue hose. The pump does cycle properly for all other lines and there are no leaks. Hard to see the side of the pump through the little lid in the cabinet, but maybe that is where the blue hose gets it's only water feed? But how does it get city water in the line? I'll dig come more and report back.

[Morich]

A bit more looking at the pictures!

I see the main fresh water feed coming in to a tee at the edge of the tank. That tee then goes up to the suction valve, past it and on to the small filter at the input end of the pump. If this filter is okay to pass water, it goes up and winds up at the main filter above.

Maybe worth checking the small pump filter is clear and find it is getting water?
Do you get water into the tank okay when switching the selector valve at the wet bay connection?
I'm having trouble seeing how you get pressure to the main filter if it passes the tank tee with nothing to keep water from going into the tank??



I'm missing something as I see nothing to keep pressure water coming to the tee from just going into the tank and out the overflow??


I am messed up some way? Maybe you can spot what or how they keep the tank from overflowing if freshwater is getting to the main filter?

[N1ven]

The tank fills perfectly from the wet bay connection valve (Tank Fill vs. Normal). It overflows if you fill it too much so they say to open the manual fill cap to vent and handle the overflow, which I've done. Also, the water pump works well, cycling on and off for the hot water to the sink and both hot and cold water to the shower and bath sink, and the pump filter looks clean. I will remove the small pump filter cover, check the filter and reinstall the pump filter cover. Water is pumped from the fresh water tank for all other purposes, so the bath sink and shower has both hot and cold water and the galley sink has hot so the pump has good throughput. Thought the on-off-hot-cold valve at the galley sink might be bad (no cold water) but while replacing the Culligan filter I confirmed that there is no water pressure in the 3/4" tubing feeding the filter (and external faucet) whether pump is running or not and even if put on city water service. Something is stopping water from getting to the blue tubing at about that siphoning valve you first identified. Hang in there, we'll get it.

[Morich]

Giggle or headscratcher for the day?
Under the Truma, it's like they had too many parts and needed to use them up!


With the bypass, etc. it kind of reminds me of a newish intersection we have near me. Called a displaced left turn, it is mindboggling to folks who have not seen one!

Will continue to study as time allowed. Wonders of the internet allow me to set and wait while folks get around to getting back to me on work stuff, so I have lots of time to look at RV stuff!
Back in the old days, we called and asked questions and got immediate answers. Now we save time by ignoring everybody else and they lose the time! I do like being able to send drawings and mark them up to cut confusion but it can take days to do a 30 minute job!

I will continue to look for something I'm missing!

[Morich]

Getting lots of weirdness in what I'm seeing, Water flow is not what I would expect as it seems to reverse the direction of flow to most of the RV, depending on whether you are on pump or city pressure!
Not really used to seeing that but there are some things that I feel have to be true! At the pump, water normally HAS to come in through the little filter first as a way to keep tank debris out of the pump! But there is also normally a check valve (one way) in the pump to keep city pressure from going backwards through the pump as it lets the tank overflow when not using the pump and hose is connected!
What I am seeing is odd but then the Truma is a different setup, so maybe they went wild?


Big question? Is this RV new to you and do you know that faucet worked at one time?
How much of the filter connections can you see?
Is there any chance the two small filter lines are reversed and some form of check valve in the filter housing is stopping flow due to it being reversed?
Any idea of history on the filter and housing to know if it might have been changed from OEM to one that needs connected with "IN" and "OUT" different?
Running out of ideas!!!

[Morich]

Okay, time to get straight! I had an eye-opener thought that clears lots of my confusion!
Reason the hose doesn't continue to fill the tank to overflow? DUH!
Because we are supposed to be smart enough to turn the hose off or change the selector vale back to normal! I was sleep walking past that and it was giving me all kinds of confusion!
When we fill the tank, water comes in from fill port goes clockwise, if we are looking down on the RV, and to the tank.
If we turn off the hose and use the pump for water from the tank, it continues in a clockwise circle through the pump and goes to the back for exterior, Truma, and up the driver's side to shower, stool, etc!
When doing this, is should also go up the small tube to the filter and on to the faucet that is the problem!

But if we want to use the pressure water and put the selector valve to normal, water goes in a counter clock route! Input port to Truma area, exterior, and then back up the passenger side, past the trouble faucet and stopped from going through pump "backwards" by an internal check valve!
Seeing what looked like reverse flow was messing with my mind and I got hung up thinking I was missing some valve!
Click for best view!


So I was making a big question out of simple!! There is no other valve, etc shown on the OEM drawings. If you can get city water to the exterior faucet and then get pump water to that faucet, it seems it has to be going by the Tee where the big filter and trouble faucet split off!

I'm not sure what you can get to for checking but there has to be some form of clog, right in the area close to the filter and faucet!
Maybe debris stuck in the tee or line? Maybe a filter housing with check valve turned wrong?
If not getting water to the filter, that puts it into being something plugging that one small line from where it passes the tee and goes up and into the filter!!

[Ray,IN]

It's just that one line, correct?

Try turning off all water sources, drain plumbing. open kitchen cold water faucet. Then try blowing 50psi compressed air into that water softener line. That will prove one way or the other if it is blocked. If it's actually a blockage the air pressure should blow out the blockage, It it's a valve it should show itself.

[N1ven]

Yeah, just that blue line from pump area back to the exterior faucet in back. I'll dig around the pump as well as I can through tiny trap door in the bottom of the cabinet to see if something looks crimped or blocked. Then I will do a winterizing blow-out at 30PSI (manual says not to exceed 30, but water pressure might be about that so may not be enough) into the system and see if anything comes out the galley cold line or external faucet. Actually, will try to blow from sink faucet to push any blockage backwards. Might be like my dad's method of finding a short in vehicle wiring... bypass the fuse and look for smoke. Thank you guys.

[Morich]

Just low level logic says the block should be in or near the smaller line.
Idea is that things that can move so far from the tank will have to go through the pump and that likely gets caught in the small pump filter, so I say no junk coming that way? But something coming from the pressure/city water side will have gone through a lot of 1/2 inch line and that seems like it would be very likely to stop at the el where the tube reduces to the small filter line?
But that is where it gets tricky on what you can see and get to for working on it!
Is this faucet a cartridge type? It might be easy to imagine a small bit of plastic, etc. going into the cartridge on the cold side and stopping things there??

As the old boy on TV used to say, "Interesting, very interesting!"
About all I can add is to wish you luck and do let us know what you find!

I spent a good part of today fighting with an irrigation head that just would not act right! I finally took it totally out and found there was small rock pellet that would pass through most of the line but when it turned the right way would go into the popup of the sprayhead and almost stop the water flow. Something shaped like a mini football with stubby ends?
Run air in at the sprayhead and it seemed fine and would last for a bit when I turned the water on, but then in 10-15 minutes the water almost quit.

Since the system has not been open in about three years, where has that rock been all this time and when/how did it get in??

I'm hoping you don't have to dig up the yard to find your problem!

[N1ven]

Called the Phoenix Winnebago service dept two days ago and left a somewhat detailed message asking for a callback. Not holding my breath. Finding the previous owner is likely as difficult as finding where my adopted cousin Vinny came from before he was dropped off at the fire department. Bottled water is looking like the solution, but I won't give up.