Fresh water tank won't completely fill

lwg · 06-10-2014, 06:22 AM

We seem to consistently have a problem where we can't fully fill our fresh water tank. I usually can only get the tank to show 1/3 full before the overflow tube well, overflows. Prior to our last move over time it slowly starting filling up more and more. I think this might have been due to me "resetting" the coach with the level-up system and possibly removing an air bubble? This is my best guess so far.

We know it's not full as we can currently barely get two loads of water out of it and maybe a shower. Best estimate is that this should be no more than about 25 gallons of water.

Thoughts?

spindrift · 06-10-2014, 04:19 PM

When you say overflow tube, are you talking about the clear tube under the frame rail. Many folks have had issues with the tank siphoning its contents.

atom ant · 06-10-2014, 05:01 PM

There are three tubes to think about. There is the blue one out the bottom of the tank that drains it, another blue one that comes off the top somewhere that starts shooting water at 2/3 full and nobody really know what its for, and the regular overflow that is hiding in the frame up by the water line drains (blue and red). To get a full tank, plug or valve that blue one with no valve on it, and let it fill on up to the overflow.

I'm speaking for mine, but so far it seems to be a consistent design.

lwg · 06-10-2014, 05:06 PM

So is there another overflow valve other than just the blue line? Would hate to plug it and it overflow into the belly of the coach?

I'll probably drop the belly here in about a month. Need to make a few changes to some things, maybe it'll all make sense at that point.

0nTheRoad · 06-10-2014, 05:24 PM

On mine the second blue tube was not exposed, i just noticed water dripping from the pan one day and on investigation found this blue 1/2" pex pipe laying up in the framework dripping fresh water.
First I drained the fresh water tank with drain [the other blue pex that is exposed with the valve]. That stopped the dripping.
Next I cut an additional hole in the pan and rerouted the dripping pex outside under the coach
Then I put a valve on it...I open the valve while filling the tank, then close it to prevent dripping.

So fat that has solved my problem.

atom ant · 06-10-2014, 06:53 PM

Here is how mine is laid out - Main drain on the left, weird overflow on the right that I valved for filling to the top:

And the actual overflow the flows when the tank is full. (inbetween the main system low point drains.)

lwg · 06-10-2014, 07:23 PM

A picture is worth a thousand words. Your pics are exactly how mine is laid out. So just so I'm perfectly clear, the white line next to the hot and cold drain lines is the actual fresh water tank overflow line?

So what is the actual function of the blue line? I will close it off like the fresh water drain line in the next day or two. Once I do this do I ever need to open this valve again?

atom ant · 06-10-2014, 07:44 PM

The white line comes out of the tank at the top near the fill line. Normally this would go to the fill line hatch and connect to the small hole next to the fill line, but because it is inside the unit, they ran the white down to ground instead. Some would call it a vent, some would call it an overflow. Regardless, water comes out when its full. I found it when I had the basement wall down.

The blue line is a mystery to me. if it was intended to be an overflow, its too low, and once it starts flow, it can syphon a significant amount out of the tank. I valved it and keep it closed normally, but open it when filling just in case I'm completely wrong

. I close it when water starts flowing and force water up to the white overflow.

spindrift · 06-10-2014, 07:53 PM

Craziest darn plumbing system I've ever seen.

atom ant · 06-10-2014, 09:19 PM

ah but it works. I just re-winterized yesterday and was a little nervous missed something last fall with a new rig and lots of water gadgets. Everything tight! It just takes forever to fill and drain this 100 gal water tank to flush it

lwg · 06-11-2014, 12:22 AM

Quote:

Originally Posted by atom ant

ah but it works. I just re-winterized yesterday and was a little nervous missed something last fall with a new rig and lots of water gadgets. Everything tight! It just takes forever to fill and drain this 100 gal water tank to flush it

I'll second that. Even when the lights show "E" I'm amazed at how long water continues to flow out.

So I'm going to add the valve to the other blue line tonight. Until I get a chance to open her up for inspection I'll keep an eye on things to ensure I'm not flooding something. I'm going to figure the logic out on this once I get her opened up. Might need to call Redwood and see what's going on as well.

I prefer to understand as much of the Redwood inner workings as possible!

lwg · 06-11-2014, 05:00 AM

Ok, installed the valve tonight. Tomorrow I'll know if it works!

spindrift · 06-11-2014, 01:42 PM

Hurry, inquiring minds want to know!

atom ant · 06-11-2014, 05:17 PM

I have the wrong computer with me, but I wonder if it shows on all those Redwood drawings I've been downloading from the other site. I'll have to check it out.

NW Snowbirds · 06-11-2014, 06:24 PM

Quote:

Originally Posted by atom ant

I have the wrong computer with me, but I wonder if it shows on all those Redwood drawings I've been downloading from the other site. I'll have to check it out.

Of course not!

Terry

0nTheRoad · 06-12-2014, 03:30 AM

Nope, nothing on the drawings.

lwg · 06-12-2014, 05:28 AM

Quote:

Originally Posted by spindrift

Hurry, inquiring minds want to know!

It seems to have worked. The clear hose eventually had water flowing out of it. Problem is the lights for the fresh water tank still never showed more than 1/3 full. Wondering if something is on the sensors. A few weeks ago I sanitized the tank and it took forever to get all the bleach out. Wondering if that fouled up the sensors.

lwg · 06-16-2014, 07:27 PM

Quote:

Originally Posted by spindrift

Hurry, inquiring minds want to know!

Well it doesn't seem to be working. It seems to fill a little more and then eventually water pours out of the overflow. Also I can't get more than the 1/3 light to light up on the tank monitor...

I'm going to pull the underbelly and take a look in a few weeks. I want to install some automatic sensors for my RO system so it will turn on when the tank is low and turn off then it's full. Tired of messing with it after 9 months... Maybe I'll take a look at the monitor wires while I'm down there.

That being said, what's the best way to get "decent" access to the fresh water tank? Do I go from below or remove a bunch of things from above?

spindrift · 06-16-2014, 07:31 PM

On the FL model it's a fairly simple procedure of removing the corrugated plastic underbelly shield. Again, on ours, that would be the first plastic section towards the front of the coach. You can see the entire fresh water tank from that position.

brenkco · 07-02-2014, 05:48 PM

I have been in touch with Crossroads regarding this issue. They did not recommend attaching a valve, however there is no practical way of filling the tank without one. I am waiting for their reply.

I did however get a diagram for the fresh water system.

It seems that they are a bit over cautious. There is an overflow drain next to the fill tube. Also, if the overflow tube is inadequate to handle the volume, the fill hose will be kicked out of the fill tube. I have no idea why they feel a third overflow is necessary.

I have heard of folks with "closed, power fill" systems forgetting to vent the tank. The result is a bursting tank and structural damage to the rig. I can't see how that is possible with an open system such as ours.

A valve for me!

Ken

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