Water Leak Under Bathroom

[Doug C]

Note: I posted this under "Plumbing" because that's where I thought to put it at first. Now I'm figuring that " General Repair" might be a better place. I'll try to figure out a way to delete it from the other spot so it's not up twice. Sorry if this isn't quite the right way to use the forum. I'm new and learning.

1992 25’ Excella: We just bought this trailer last fall. I put new brakes on it and packed the wheel bearings, and did a few other small repairs. Then I winterized it according to the Airstream manual (blew out the water system and filled it with antifreeze.) and it sat for the winter. We never even got a chance to test it out on a trip. I just de-winterized the trailer in preparation for our first trip and need some help. After I rinsed out all the antifreeze and pressurized the fresh-water system, I noticed the center of the bathroom floor carpet is wet. With the system pressurized, water also slowly drips from two drain holes in the corners of the pan that is under that area of the trailer. The water stops dripping when I de-pressurize the system. I’m assuming a water line under the bathroom is leaking, but I don’t know the best way to access the water lines for a look. I don’t know how these trailers are put together. I have decent home-repair skills, but this is our first RV. I’d like to learn to do necessary repairs myself, unless a particular problem is known among Airstream owners to be worth taking to a professional repair shop. Any help would be really appreciated.

[perryg114]

The toilet fill valve is one that freezes unless you remembered to flush the water out of it when you winterized. It is at a low point and water collects there. You could have other problems as well. Usually you can gain some access to plumbing under the sink. Make sure you get the floor dried out when you fix the leak or you will have rot problems.

Perry

[Doug C]

Originally Posted by perryg114

The toilet fill valve is one that freezes unless you remembered to flush the water out of it when you winterized. It is at a low point and water collects there. You could have other problems as well. Usually you can gain some access to plumbing under the sink. Make sure you get the floor dried out when you fix the leak or you will have rot problems.

Perry

Thanks. I flushed antifreeze down the toilet when I winterized. Would that take care of it? I can't find any sign of leaking when inspecting the visible stuff under the sink. The weird thing is that it's wet in the center of the bathroom floor, but the carpeted raised area where the toilet sits isn't wet. It's like the water is coming up from underneath somehow. I can't figure it out. Not yet anyway.

[perryg114]

You mean you flushed the antifreeze through the fresh water lines or just dumped it into the toilet and flushed it. The latter won't protect the fresh water inlet valve that adds water to the bowl when you flush.

Perry

[Doug C]

Originally Posted by perryg114

You mean you flushed the antifreeze through the fresh water lines or just dumped it into the toilet and flushed it. The latter won't protect the fresh water inlet valve that adds water to the bowl when you flush.

Perry

Thanks for the response. First I blew out all the lines with compressed air. Then I disconnected the intake line at the on-board pump, hooked up another hose, and pumped antifreeze through all the lines, including shower, toilet, toilet washer, etc. I followed the steps in the Airstream manual, step by step. Still haven't figured out what happened.

[wasagachris]

You didn't mention it, but did you bypass and drain the water heater while winterizing?

[Doug C]

Originally Posted by wasagachris

You didn't mention it, but did you bypass and drain the water heater while winterizing?

Yes, I bypassed and drained it. Thanks.

[perryg114]

I does not sound like a freeze related leak then.

Perry

[Doug C]

Originally Posted by perryg114

I does not sound like a freeze related leak then.

Perry

Thanks. I found at least part of the leak. I don't know how I missed it until now, but the nozzle on the toilet wash-down hose was leaking some water every time the toilet was flushed. The toilet wasn't flushed much during de-winterizing but I did run it through a few long flushes to get some water in the holding tank so it could slosh around and clean the inside. Hopefully, this leaky nozzle will account for the entire leak. I'll know in a few days. Thanks for your help.

[Doug C]

I think I found the rest of the leak. The floor was still getting wet after eliminating the nozzle as a factor, so I took the nuts off that hold the toilet down and pulled it away from the wall a bit. The valve at the back was leaking and there are rusting corroded parts, basically a mess. Plus the floor around the toilet base is just particle board which surprised me and is all black and kind of moldy. (I was expecting high-grade marine plywood in an AS.) Does it make sense to just replace this instead of the toilet. That's my plan. Availability? I have a photo of the valve, but I'm not sure how to upload it so I'll listing the link.

AS_toilet_valve.jpg | Flickr - Photo Sharing!

[perryg114]

The rust is not the valve but the mounting bracket for it. Those valves run about $50 and are pretty common. All you need is the model of the toilet. The valve is a low point in the system and it is not uncommon for them to leak come spring time. Mine was leaking when I bought the trailer.

Perry