Fresh water leaking thru coroplast - power fill with frozen overflow pipe?

[steve&renee]

Bad news.

I was filling my fresh water tank with the Nautilus valves set to "Power Fill" -- waiting for water to begin overflowing thru the overflow pipe/valve, which is how I determine the tank is full.

Instead of water overflowing through the overflow, water started leaking (flowing) out of the middle of the Coroplast, right behind the axle. Coroplast began sagging, too.

I shut off the water and stopped filling the tank. After about 35-45 minutes, the flowing water had slowed considerably.i The tank sensor is showing 3/4 LED's (was 4/4 20 minutes ago).

As I've posted recently, it's pretty cold where I'm living in the RV right now. My guess is my overflow pipe/valve froze, and the filling water pressure resulted in a fitting failure in the fresh water tank. I've searched the forum, but I 'm unable to find any diagrams of the fresh water tank plumbing. I'm guessing it looks something like this:



I'm hoping I might get lucky and have a partial failure in the "City Fill" fitting that goes into the top right side of the tank. That would buy me some time: I could keep the tank 3/4 full for sink and toilet, and temporarily hook up to "City Water" for showers each morning.

Looking for diagrams and/or suggestions. My goal is to stay in the RV until the house is finished -- around the end of January. That's now looking like a long time coming.

-Steve

[TedS]

Unless somehow water remained in the overflow/vent there should be no ice in the overflow. Maybe ice in the tank floated and blocked the overflow port. Worst case, cracked the tank.?? Not a fitting.

A frozen ice plug may have caused the drain valve to crack above the coroplast.

[Country Campers]

steve&renee

The fill tube for the fresh tank is also the supply tube to the pump, the valve at the Nautilus panel determines which way the water goes. There is a small , maybe 4" square drop sump in the fresh tank where this connection is . The over flow pipe is about straight above this about 1" below the top of the tank, this is a located in the same area as the fresh tank drain. You could remove a few screws holding the coroplast right at the frame where the fresh tank drain is and have a look to see if anything is broken. You may want to put some foam around the drain and over flow to keep them from freezing, the low point drains as well. If these items have been exposed to the elements it is possible that they may have frozen and broke. The fresh tank fill/supply line will be pretty close to the coroplast.

Brian

[steve&renee]

steve&renee

...
You could remove a few screws holding the coroplast right at the frame where the fresh tank drain is and have a look to see if anything is broken. You may want to put some foam around the drain and over flow to keep them from freezing, the low point drains as well. If these items have been exposed to the elements it is possible that they may have frozen and broke.

...

I'll remove some coroplast fasteners tomorrow in hopes of further defining the problem. Doesn't seem likely to me that I'll be able to replace fittings or piping in a space that cramped. I'm thinking all the coroplast behind the axles is going to have to come down to effect a repair.

I don't see that the tank drain and low point drains have any bearing on this particular failure. I'm still suspecting my overflow pipe. I agree with TedS that the pipe exiting the tank probably didn't have water, because any water at the tank exit would have drained back into the tank. But I extended the overflow pipe with my own horizontal pipe and shutoff valve so I wouldn't lose freshwater driving down the road. That horizontal pipe may have had standing water that froze and caused unacceptable pressure build-up in the fresh water tank and its fittings when I was power filling.

Just guessing, though. Hopefully I'll see something tomorrow.

-Steve

[howson]

steve&renee -- the diagram is post #1 is close. It won't tell you more than you already know, but if desired ask GD for a "WATER SUPPLY PLAN" drawing for your 310GK.

Hope you're lucky -- when I overfilled the washer tank in my 315RLTS it split at the top of the tank. I have yet to drop it and attempt a repair (I bought a Plastic Welder)...for now I just leave the drains open and it's fine as the waste water never reaches the top of the busted tank.

[TedS]

I'll remove some coroplast fasteners tomorrow in hopes of further defining the problem. Doesn't seem likely to me that I'll be able to replace fittings or piping in a space that cramped. I'm thinking all the coroplast behind the axles is going to have to come down to effect a repair.

I don't see that the tank drain and low point drains have any bearing on this particular failure. I'm still suspecting my overflow pipe. I agree with TedS that the pipe exiting the tank probably didn't have water, because any water at the tank exit would have drained back into the tank. But I extended the overflow pipe with my own horizontal pipe and shutoff valve so I wouldn't lose freshwater driving down the road. That horizontal pipe may have had standing water that froze and caused unacceptable pressure build-up in the fresh water tank and its fittings when I was power filling.

Just guessing, though. Hopefully I'll see something tomorrow.

-Steve

So there is more to the story; non-standard vent/drain. Hard to troubleshoot when blind.

[steve&renee]

I dropped the coroplast to get a look at the tank and fittings. Removed the coroplast fastening screws on the overflow valve side from the rear axle to the back end of the trailer. That was enough to see the bottom of the tank, overflow and intake fittings, but not much more. So I cut the coroplast from the driver's side to the curbside. Before cutting, I was able to confirm a cut-line that was free of electrical wires. I'll figure out how to re-install the coroplast later.

The insulation laying on top of the coroplast was soaked and dripping profusely. I pulled out all the insulation and can't see any visible leaking. I felt around the tank inlet fitting, the overflow fitting, and the dump valve fitting. None of the fittings were wet or even damp. Here are some pics (mostly looking up):

[Country Campers]

Have you filled the tank while you have it open to check for leaks? You may also want to run the pump or attach to city water to check for leaks.

Brian

[steve&renee]

I did discover that the horizontal overflow pipe and valve I added to the vertical OEM overflow pipe was frozen solid. I cut the horizontal section off. The vertical section of the pipe was pretty free of ice. I'll heat it up with a hair dryer before re-filling the freshwater tank. (I added a horizontal pipe section and valve to the overflow to prevent losing freshwater while driving. The horizontal section was to be able to reach the valve without crawling under the trailer.)

So for now, I'm at a loss in understanding the source of the leak. My plan is to re-fill the tank while watching for leaking later this afternoon. I'll report the results when they're available.

There was a mysterious manufactured hole in the tank that I didn't understand. The inside of the hole was dry to the touch. Here are some pics:



If anybody has an idea about this hole, I'd like to hear it.

-Steve

[Country Campers]

That "hole" is in the center of the tank to add a little rigidity to the top and bottom of the tank.

Brian

[steve&renee]

[QUOTE=steve&renee;n71265
...
My plan is to re-fill the tank while watching for leaking later this afternoon. I'll report the results when they're available.

[/QUOTE]

Country Campers TedS howson

Started filling the tank again this afternoon -- looking for leaks, especially at the intake and overflow fittings. Started filling from about 3/4 LED sensor lights.

For the first minute or two, no leaks, dry fittings.

Then the leak began to flow. It originates almost dead center in the bottom of the tank, right under the stick-on tank heater. See pic:


I think it's just one flow that divided along the edge of the heater pad. Can't see a crack or a hole because the pad covers it.

Before I started filling the holding tank again, the leak had stopped. The process of filling started it leaking again. My guess is it's a crack that leaks water when the tank is under pressure from filling. Remove the pressure and the crack seals up -- for now.

As I indicated in another posting, my goal is to limp along until the end of January. Any thoughts about pealing the heating pad off and applying some heavy duty mastic to effect a temporary patch? Today it's almost 50 degrees F during the day, and they're forecasting the same for Wednesday. Whatever I try, I'm thinking I have just a short window to get the job done.

-Steve

[Country Campers]

Steve

I would for sure try a patch job while the weather is right. You may also want to put a support under that portion of the tank. Just a guess might the pressure from filling or the weight of the water may be sagging the tank just enough to open the crack, a support may help the matter as well as patching. Just remember that the support is there if you auto level or the trailer settles, a bottle jack and a long block of wood, 2 x 6 x 36" long or so may do the trick, the bottle jack you could raise and lower if needed. You sure are in a predicament with trying to hold on thru winter.

Brian

[Cate&Rob]

Hi Steve,

That is really curious that a crack would occur in the middle of the bottom of the tank. Not typically a stress point. Is it possible that the tank heater had something to do with this? Was it on when the tank was empty? How is the water getting through the heating pad? To effect a "temporary" repair, you are going to have to find your way to the leak. If you are sure that the leak is under the heating pad, pealing it off seems like the only course of action.

Rob

[steve&renee]

Hi Steve,

That is really curious that a crack would occur in the middle of the bottom of the tank. Not typically a stress point. Is it possible that the tank heater had something to do with this? Was it on when the tank was empty? How is the water getting through the heating pad? To effect a "temporary" repair, you are going to have to find your way to the leak. If you are sure that the leak is under the heating pad, pealing it off seems like the only course of action.

Rob

I don't *think* the tank has ever been empty enough when I've had the heater pad on to cause any damage -- but this location sure seems mighty coincidental.

I did some tentative tugging on the heating pad. Some of it is sealed/stuck-on really well, other sections not so much. I just got off the phone with the service manager at my dealer. He said people have had pretty good luck with Flex Seal tape. Just need to sand the tank a little to get good adhesion. I'm planning to pull the heater pad off tomorrow and inspect, then try some Flex Seal. Hope I don't make a mess or make it worse.

Country Campers Thanks for the jacking suggestion. Good idea.

-Steve

[howson]

steve&renee -- well that sucks. I hope the Flex Seal works for you...the school taught that nothing permanently sticks to the plastic (forget the exact technical term). Plastic welding is what we were taught is the only permanent repair.