We went to a local campground last night to check out our ( new to us ) 2000 Winnebago Minnie 31C. Before we left home I checked control panel for holding tanks and it said both black and grey tanks were empty, I even pulled lever on grey water tank to make sure and it was empty. We hooked up to campground water and electric ( no sewer hookup ) to test everything. We ran a little water in sinks and flushed toilet six times. By morning black tank was full, toilet would not flush and grey tank was at least half full when I went to dump station. I don't know if I did something wrong or if I didn't do something I should have or if I have a major problem. Any ideas would be helpful.

Toilet would not flush? What does that mean? Level indicators are notoriously inaccurate. If this was your first trip of the season all of the sensors should've been dry to start with. If there was any TP on the sensors in the black tank, that would've gotten wet after a few flushes.Does your bathroom sink drain into the black tank? What are your tank capacities?

You say you were hooked up to campground water. Perhaps the spigot was shut off where you were hooked up to the water. When, you say, the toilet didn't flush could you still get water to come out of the faucets in the sinks? Did you have water in the fresh water holding tank? Was your on-board electric water pump turned on?By the way those gauges to indicate the level in the holding tanks never work right. We haven't looked at our gauges for ten years now. We determine the fullness of our tanks by how much we have used the toilet and ran water in the shower and sinks.

gauges are worthless as said ,we keep a flaslight in the cabinet and look down the hole ,your blk tank could be full if a faucet leaks or your flush unit leaks. all in the fun in learning about your camper.

Any idea how much fluid actually came out when you dumped? How long did you hold the valve open when you flushed?If the tanks were really that full when you dumped you either used a lot of water when you flushed or you have a leaky valve, but even a leaky valve should leak into the bowl, not into the tank.

Are you sure you had your water hose hooked up to the right city water connection and not to some type of tank flushing connection ?My Itasca MH has two side by side hose connections, one for city fill, the other for tank fill. The second time I used the MH I mistakenly hooked the fresh water hose to the tank fill, instead of the city fill. I went off for a while and when I got back to my site a neighbor told me water was leaking from my MH. Only took a couple of seconds to figure out what I had done wrong. Fortunately the overflow on the fresh water tank worked as it was supposed to and nothing happened to the MH, with the only issue being God only knows how much water was wasted.I've had a number of RVs and this is the first that didn't have a gravity feed fill for the fresh water tank and a screw on connection for only the park water connection. Just a few seconds of not paying attention in my case, since I've been hooking up hoses forever, resulted in me hooking up to the wrong connection. :o

Holding Tank Filled Overnight | Good Sam Community

pnichols
Explorer II
May 13, 2014
Showing tanks empty for awile. then full(er) later, seems a bit of a reverse situation to me.

Our stock Winnebago's through-the-tank-wall sensors used to occasionally show fuller than they actually were before I started using an additive to stop the erroneous readings.

I've never heard of acting-up sensor readings showing as the OP described.

By the way, one can ALWAYS see if the black tank is getting critically full by opening the toilet valve and looking down it with a flashlight.
fairway1
Explorer
May 13, 2014
After checking the bathroom sink, as many of you said, it does drain into the black water tank, so it looks like the bathroom faucet was my problem. Replaced bathroom and kitchen faucets with residential ones. I had city water hooked up all day and had no problems. Thanks for all the information.
TyroneandGladys
Explorer
May 01, 2014
fairway1 wrote:
I didn't mean to confuse anyone when I said toilet wouldn't flush, I meant I couldn't flush it because when I did the tank was so full the bowl just filled up. The bathroom faucet did drip all night but I don't know what tank it drains into.We didn't do any dishes or take any showers so I don't think water usage was the issue. From your responses it sounds like level indicator for black tank is faulty and bathroom faucet dripping all night may be the cause.

Confused by the statement "I meant I couldn't flush it because when I did the tank was so full the bowl just filled up"
A rv toilet has a two stage pedal the first stage adds water to the bowl the second stage opens the flap in the bottom of bowl dropping the contents down into the black tank. My question is when you flush do you see the flap in the bottom of bowl open? IMHO it seems very likely that you did not step down completely on the flush lever or that the connection from the lever to the flap is broken.

Please post what you find
4x4van
Explorer III
May 01, 2014
While camping this past weekend, a friend asked me about the dreaded TP teepee, as his toilet seemed full on the first day. He drained the tank, but it was still full up almost to the bowl. I looked, thought he had a teepee, and got a stick to push it around. Turned out that it was just a clog of TP and waste in the neck BEFORE it actually reached the tank. One push, it dropped down into a (now) empty tank and he was good to go (literally and figuratively).
mlts22
Explorer
Apr 28, 2014
It depends on the sensors. One piece of wet toilet paper, and the sensor is fouled until manually cleaned off. Winnebago has better sensors than most (the sonar type), and there are See-Level sensors that can be added on, but the average probe type tend to give errant readings.

I'd probably see about running some tests to see what sink filled what tank. Something doesn't sound right. And like what was said above, grab a decent residential faucet and replace the old one.
maillemaker
Explorer
Apr 28, 2014
If your bathroom sink was dripping/leaking and if it drains into your black tank then your sink may have filled up the black tank.

I don't know why everyone is poo-pooing (hah) their tank sensors. On my 1990 Winnebago Warrior they work very well. Now on dumping it takes a while for the sensors to read zero as it takes a while for the tank walls to un-wet. But on the filling up side of things, they are pretty good indicators of what is going on in the tanks for us.

Steve
Old-Biscuit
Explorer III
Apr 27, 2014
Fix that dripping bathroom faucet....replace with a good quality residential one.

Black tank full enough you can not flush toilet....then tank was full.

Might want to fill black tank and then use a 'digester' treatment. Unique makes a good one. Let it sit for as long as you can so digester can clean/break down stuff that may be built up in tank. Then drain and flush tank.

After draining/flushing...add couple toilet bowls back into black tank so bottom stays wet and stuff doesn't stick.
GrumpyandGrandm
Explorer
Apr 27, 2014
Draining a sink into the black tank was a norm for some manufacturers to be sure you had enough water in the tank when you went to dump. I haven't heard of it being done in recent years and I don't think the RVIA code allows it anymore as well.
CloudDriver
Explorer
Apr 27, 2014
We have a 2003 Winnebago Minnie 24ft. The toilet drain is a straight down drop into the black tank. To check the level in the black tank, we shut off the water and any vent fans, open the toilet drain valve and use a flashlight to take a look - being very careful not to drop the flashlight. Much more accurate than the tank gauges. Our bathroom sink does drain into the black tank.

Since this is a "new to you" RV, I wonder if the previous owners left the black drain valve open, thus creating the dreaded "poop pyramid" which has partially filled the black tank.
fairway1
Explorer
Apr 27, 2014
I didn't mean to confuse anyone when I said toilet wouldn't flush, I meant I couldn't flush it because when I did the tank was so full the bowl just filled up. The bathroom faucet did drip all night but I don't know what tank it drains into.We didn't do any dishes or take any showers so I don't think water usage was the issue. From your responses it sounds like level indicator for black tank is faulty and bathroom faucet dripping all night may be the cause.

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