Main water line blew off, flooded underbelly

[UnMayor]

We've had our 378 MBS for not quite a full year, and this evening while we were all sitting in the living room watching a movie, we heard a sudden PSHHH. My wife and I thought nothing of it, thinking one of the kids had slid a box across the floor or something.

About an hour later my wife goes to use the bathroom, and there's no running water. So I step outside and hear copious amounts of water dripping from underneath, immediately turn off the water, and see the coroplast drooping.

It's almost 11 at night so I got my flashlight and began unscrewing the covering, and out comes tons of water. I then crawled in the pass thru to remove the wall and when I do I see the main line going into the water heater hanging free.

Tomorrow is our departure day, so I will be dropping it off at the nearest dealer. My main concern is the moisture causing any future problems, and also it happening again.

Any thoughts on what could have caused this? The fitting itself is not a design I like at all as the only thing holding the barbed end in place is the tension from the nut compressing the rubber bushing.

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[FlyStar]

Wow. Agree that the fitting is not the best. First thought is too much pressure. Either from the campground, pressure regulator failure, or the water heater. I have noticed that when I first start the water heater, the pressure is high right after it gets warm. Probably compressing air in the water heater tank. This goes away after the first use or sometimes the overpressure valve on the tank sputters it out.

Second thought is the fitting came loose from traveling or was never properly tightened.

Perhaps someone here on the forum can recommend a way to achieve a more secure connection system for the hose.


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[BobLandry]

Replace the tank fitting with a barbed fitting to match the hose I.D. and use a SS hose clamp to secure. If you can't find a fitting locally, McMasters-Carr is a good bet.

[Ynot4me2]

I think using a pressure regulator is the only way to try and prevent this. It's not 100%, failures from parts braking or not properly installed can happen any time. Our rigs are always exposed to earthquake vibrations when rolling down the road.
As for dropping it off at the dealer, they most likely won't have time to look at it for weeks maybe even months given today's crazy rv market. So moisture will be a big issue. If you can bring home, then I'd open up everything that I could including the coroplast where there's water and set up fans to dry thing up for a few days. This will give you time to call your dealer or a mobile tech.

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[stroguy]

Possibly a combination of things. Factory did not tighten the fitting correctly, over tight or not tight enough. Should be damaged threads if they over tightened.

Water pressure was too high, or a surge of water pressure. My main water line sprung a leak from just a bit too much pressure about a year ago. I flirted with my regulator and went a little above 50 psi and I guess that was enough to fail the fitting. Not a blowout like yours but a mess as well. I never run over about 42-43 psi now. Wife doesn’t complain so it is good for me.

Or heated water cause back pressure on the line. I saw a friends hot water line blowout on the input side. It was a big mess similar to yours. We weren’t at the site and a neighbor saw the water and felt the hot ware leaking and turned the water off. I make my best efforts to always turn the main line to the RV off whenever we depart for an extended time.

Good luck to you.

[Maximus216]

I have the same problem but not has bad as yours. Yesterday, my hot water heater started to leak. I saw water by the steps going up to the bedroom. I took the drawers out of the hutch and saw water dripping from the cold water intake. I don't have a check valve like yours, looks like just a 90 degree elbow. I'm camping so i don't want to tackle this at the camp ground so i turn off the water and i'm just using the water pump from the fresh water tank. The leak has stopped for now. I had my pressure regulator set between 50 and 60. That might have caused the issue.

[Maximus216]

We've had our 378 MBS for not quite a full year, and this evening while we were all sitting in the living room watching a movie, we heard a sudden PSHHH. My wife and I thought nothing of it, thinking one of the kids had slid a box across the floor or something.

About an hour later my wife goes to use the bathroom, and there's no running water. So I step outside and hear copious amounts of water dripping from underneath, immediately turn off the water, and see the coroplast drooping.

It's almost 11 at night so I got my flashlight and began unscrewing the covering, and out comes tons of water. I then crawled in the pass thru to remove the wall and when I do I see the main line going into the water heater hanging free.

Tomorrow is our departure day, so I will be dropping it off at the nearest dealer. My main concern is the moisture causing any future problems, and also it happening again.

Any thoughts on what could have caused this? The fitting itself is not a design I like at all as the only thing holding the barbed end in place is the tension from the nut compressing the rubber bushing.

Sent from my SM-G960U using Tapatalk

I'm having the same issue as you, but mine is just a drip for now. I don't have a check valve on the cold water inlet and after reading and watching videos, some are saying that you don't need one on the cold water , just the hot water.

[Redapple63]

We've had our 378 MBS for not quite a full year, and this evening while we were all sitting in the living room watching a movie, we heard a sudden PSHHH. My wife and I thought nothing of it, thinking one of the kids had slid a box across the floor or something.

About an hour later my wife goes to use the bathroom, and there's no running water. So I step outside and hear copious amounts of water dripping from underneath, immediately turn off the water, and see the coroplast drooping.

It's almost 11 at night so I got my flashlight and began unscrewing the covering, and out comes tons of water. I then crawled in the pass thru to remove the wall and when I do I see the main line going into the water heater hanging free.

Tomorrow is our departure day, so I will be dropping it off at the nearest dealer. My main concern is the moisture causing any future problems, and also it happening again.

Any thoughts on what could have caused this? The fitting itself is not a design I like at all as the only thing holding the barbed end in place is the tension from the nut compressing the rubber bushing.

Sent from my SM-G960U using Tapatalk

From the pictures it does not look like anything is broken, but more looks like it popped off, I agree that it looks like the fitting was not tightened fully when installed. In also agree with the permanent use of a pressure regulator set to about 50 psi. I would reinstall and do a controlled test of that fitting and see how it does.

[jkwilson]

I have to wonder if pressure rose in the tank and opened the check valve pressurizing the line beyond the limits of that fitting.

Hindsight being 20-20, I think I’d want all threaded fittings and a good solid clamp on the barbed fitting.

I think it all comes down to a poor choice of fittings, but maybe properly installed that’s a better fitting than I think.

[pfd278]

I Put a Basement Watchdog Battery-Operated Water Alarm in the basement, and screwed the sensor to the floor near the water pump on my 310gk. It caught a minor leak I had before it got bad.