Toilet Mystery

[Fossil_Hunter]

Yesterday I took my travel trailer out of storage and moved it just a few yards to a different location. When I went into the bathroom, there was water all over the floor. When I opened the toilet, water was all the way to the top, thankfully I clean my tanks well and the water was clear. I flushed the toilet and the water went back to the tank. There can't be more than a couple of gallons in the tank as I usually add a couple of gallons with chemicals after emptying the tank.
I have never had this happen before, what could have happened?
Thank you in advance for your help.

[Fossil_Hunter]

Thanks for the replies so far.
Toilet lid was closed. Black tank only has a couple of gallons in it.
Water pump and fresh tank are never used, I only camp with hook ups.
Vent has no leaks. Pipe cap is intact on roof with no leeks.
My cleaning procedure is as follows:
Dump black completely, let run for a few minutes via black flush sprayer, when finished I close the black valve and do a 60 second count with black flush running to put a couple of gallon back in black tank. Turn off black tank sprayer.
Go into trailer, open toilet and pour in bottle of blue chemical.
Close empty toilet lid. It bugs me that the water was clear, and not blue tinted from the chemical...... The black tank is not full, when I flushed the toilet, the clear water fell into tank as normal.
To me, the water could not have come from the black tank. No water pump either, lid closed, no leaks from above. Sounds crazy but these are the facts.

[opnspaces]

only so many ways this can happen.

The fill valve is faulty and the water pump filled the bowl. You said the fresh tank is empty so this probably isn't the issue.

The fill valve is faulty and shore hose had extremely high pressure and filled the bowl. This is a possibility and you should be able to reproduce it fairly quickly.

There is a crack in the skylight and the bowl filled with rain water. I find this unlikely as I don't think Paso Robles gets enough rain to fill the bowl through a cracked skylight.

Which leaves the last possibility. You said you like to clean your tanks really well. My guess is that you lost track of time while filling the tank for a flush and the water pushed up through the fill valve and filled the bowl. Then you pulled the drain valve handle and drained the tank but the toilet stayed full of water. When you next moved the trailer the water in the full toilet sloshed over the rim and landed on the floor.

[2_many_2]

Possible accumulator tank in the system? Combined with a leaky toilet valve?

[CavemanCharlie]

You said that there was water on the floor and the toilet was full. Someone asked if the toilet lid was up and I am wondering the same thing. If it was maybe you have a roof leak and it just happens to be leaking into the toilet.

[kellem]

As someone previously mentioned, have you checked your ceiling fan vent cap for any leaks. Our is located directly over toilet.

Let us know when you find the culprit.

[learntorv]

Fossil Hunter wrote:
The water pump was not on and there is no water in the fresh tank.

Believe it or not, this is the second time in 5-6 years that I've read of this kind of toilet mystery. The first one was never solved either!

Is there any chance the fresh water tank isn't empty? A common occurrence is for city water to backflow through the water pump and fill the freshwater tank unbeknownst to the owner.

Though, with the pump off... I'm still not sure how it would make it into the toilet.

[BurbMan]

If he rinsed enough the water would be clear, but agree this is an unlikely scenario.

Most likely cause is that the OP filled the toilet with water meaning to put into a clean tank with a deodorizer, went outside to dump the tank, then forgot to come back and flush the toilet and deodorizer into the tank.

I vote 100% user error 🙂

[schlep1967]

BurbMan wrote:
Do you have the built in black tank rinser? Maybe you left the hose connected too long and the tank backed up into the toilet, then when you drained the tank the toilet didn't run back?

If the seals pushed out enough to let water into the toilet, it surely it would have slowly leaked back down into the black tank. And the water would not have been clean if coming up from the black tank.

[BurbMan]

Do you have the built in black tank rinser? Maybe you left the hose connected too long and the tank backed up into the toilet, then when you drained the tank the toilet didn't run back?

[schlep1967]

Was the toilet lid open? Check the plastic crank open vent right above the toilet for cracks. They dry rot over the years. If no water hooked to lines I'm guessing rain water from above.

[kellem]

Perhaps you didn't relieve the pressure in the lines after shutting the pump off and water found an Avenue of least resistance, toilet valve.
But your right, not heard this one before.

Water intrusion through the roof vent would have to meet black tank capacity before threatening the toilet.

[Fossil_Hunter]

The water pump was not on and there is no water in the fresh tank.
The sensors on black tank show empty, and looking into toilet with flashlight shows very little water in tank. I know it sounds crazy, but these are the facts.
That's why I am stumped........ I will check roof vent caps though although my tank isn't full.
Thank you so far for the responses.

[BurbMan]

rdhetrick wrote:
I'd guess the water pump was left on and the toilet fill valve was leaking by.

That would only be true if he left the fresh water tank full while the TT was in storage, and there was more fresh water than the black tank could hold.

You might be missing one or both caps on the roof vents. If you look on the roof there are two 1-1/2" PVC pipes that come up thru the roof and have vent caps on them. One is black tank, one is gray tank. If the cap was missing, rainwater and/or melting snow will run down the vent and fill up the tank. Once the black tank is full it will overflow from the toilet. The gray tank usually backs up into the tub/shower since that's the lowest drain.

[Old-Biscuit]

rdhetrick wrote:
I'd guess the water pump was left on and the toilet fill valve was leaking by.

Water to toilet comes from 2 places
Water Pump or City Water via hose

Toilet valve leaking thru

[rdhetrick]

I'd guess the water pump was left on and the toilet fill valve was leaking by.