Black Tank Question

[Karen S]

I just came back from a five day trip with another adult. The black tank gauge read empty on day one. By day three the gauge read full and from looking at the toilet it was full. Went and dumped the tank. Gauge read empty. On day five the gauge read full again and I had to dump it. I have a 2017 Gemini TB. The brochure says the black tank holds 19 gallons. Is it normal for the black tank to fill this quickly?

Thanks and Happy New Year.

Karen

[Beau388]

Originally Posted by Karen S

I just came back from a five day trip with another adult. The black tank gauge read empty on day one. By day three the gauge read full and from looking at the toilet it was full. Went and dumped the tank. Gauge read empty. On day five the gauge read full again and I had to dump it. I have a 2017 Gemini TB. The brochure says the black tank holds 19 gallons. Is it normal for the black tank to fill this quickly?

Thanks and Happy New Year.

Karen

Generally the bathroom sink also drains into the black tank. This is to help when you dump the tank; otherwise, you may get a POP. I have a 24 gallon BT, so I know what you mean.

[Bob Denman]

Well... it all depends on your diet...

[Karen S]

This will probably be funny when I get the problem solved. ��

[Karen S]

Originally Posted by Beau388

Generally the bathroom sink also drains into the black tank. This is to help when you dump the tank; otherwise, you may get a POP. I have a 24 gallon BT, so I know what you mean.

How often do you need to dump your BT?

[16ACE27]

19 gallons is relatively small, but think of it as 4, 5 gallon pails. That would be a lot to come from two adults in 2 or 3 days. So evaluate how often and how long you use the bathroom sink - it's the likely source of filling the black tank so quickly.

[Karen S]

Originally Posted by 16ACE27

19 gallons is relatively small, but think of it as 4, 5 gallon pails. That would be a lot to come from two adults in 2 or 3 days. So evaluate how often and how long you use the bathroom sink - it's the likely source of filling the black tank so quickly.

Thanks. I didn’t know about the bathroom sink draining into the BT.

[EA37TS]

Originally Posted by Karen S

Thanks. I didn’t know about the bathroom sink draining into the BT.

You might want to go out to the Thor Owner's Resource site, enter your VIN, and download the plumbing diagrams for your rig. The waste diagrams will show you which fixtures are drained into the grey and black tanks. It's amazing how much one can learn from looking at the diagrams.

https://www.thormotorcoach.com/owner-resource/

[Karen S]

Originally Posted by EA37TS

You might want to go out to the Thor Owner's Resource site, enter your VIN, and download the plumbing diagrams for your rig. The waste diagrams will show you which fixtures are drained into the grey and black tanks. It's amazing how much one can learn from looking at the diagrams.



https://www.thormotorcoach.com/owner-resource/

Thanks. I regularly use the Owners Resource site. I didn’t see the diagram you referred to. I’ll look more closely.

[dkoldman]

I would be curious to know what the gray tank was doing during the same time?

When you dumped the black tank did it look mostly gray?

Our Gray tank fills way before our black tank. But, our bathroom sink goes to gray tank though. I think I kind of wish it went to black tank like yours but now I am not so sure?

If you wash your hands quite a bit during covid and wait until water is warm it may be the culprit?

We have 40gal BT and 61gal GT We have gone a week with 3 adults and never got the BT past 2/3 indicator.

We seem to fill the gray tank up quickly though. All of dumping has been based on reading of gray tank, we just drain the BT because it is 1st to drain in our SOP.

[Pete'sMH]

3 days doesn’t surprise me for two people with only 19 gallons. If you’re careful you probably can stretch it a bit. If your grey tank isn’t filling as quickly you can try washing your hands and brushing your teeth in the kitchen.

[Karen S]

Thanks. The Gray tank is about 2/3 full when the black tank is full. The water from the black tank looked mostly yellowish when I dumped it.

[Bob Denman]

We fill our gray tank (32 gallons) in about two days...
But we both like long hot showers...
The black tank (28 gallons) will go at least a week...

[Campnjoe]

It all really depends on how you use it. 19 gal is really small and with priming it with water and chemicals you probably only have 16 usable. As a test, get a 5 gallon bucket and see if you can put 19 gals in it. Might have some build up in it. All in all though I could see filling it in 2-3 days.

[dkoldman]

Originally Posted by Karen S

Thanks. The Gray tank is about 2/3 full when the black tank is full. The water from the black tank looked mostly yellowish when I dumped it.

That sounds normal. And given that; you probably would not want the bathroom sink plumbed to gray tank.

I would do as it was suggested earlier. Get the plumbing diagram of the coach to verify how it is suppose to be. Once I know that, the next time at a dump station when both tanks are empty, pour 1 gallon down each drain one at a time just to confirm it goes to the correct tank on the drawing.

The idea of adding 19 gallons of fresh water to the black tank is a good one as it will then get you to the point where only factor remains and that would be bathroom sink usage.

[Bob Denman]

Minimizing bathroom sink usage:
Do your hand-washing in the kitchen sink.
brushing teeth? This has always worked well for us at Deer Camp, and also works in the RV.
grab a small cup for some water
put some toothpaste on your brush, and step outside
dip the toothbrush in the cup to wet things down
do the whole tooth-brushing thing...
grab a swig of water from the cup, and swish it around a bit
spit that into the fire pit
dip your toothbrush in the cup to stir it around a bit
shake it out over the fire pit
empty the cup into the fire pit also

Go back inside, and grab a cup of brown ambition.

[macdaddy1111]

Get yourself a dookie cam, 50 bucks amazon

Can see everything! Ha

[Bob Denman]

Do you really want to look into the black tank?
I prefer the "ignorance is bliss" approach...

[taylorbob1]

Originally Posted by Karen S

Thanks. The Gray tank is about 2/3 full when the black tank is full. The water from the black tank looked mostly yellowish when I dumped it.

We should start a new thread with a color chart.

[Bob Denman]

Originally Posted by taylorbob1

We should start a new thread with a color chart.

https://www.thorforums.com/forums/at...1&d=1609354451