Black Tank Dump - How Often??

[fansill]

Good Evening All,

We just returned from another glorious weekend in the "Big Baby" and I have another question. Usually I dump the black water tank after every outing followed by the grey water. I do this even if we are just gone for 2 days and the black tank is only reading 1/4 full. Is this advisable? I have heard that others wait until the tank is at least 1/2 or 3/4 full, but sometimes that may take us weeks or even months depending on whether we get out every weekend or have to wait for a month to go camping again. I hate to take any chances on odors building up if I leave the black tank "cooking" for weeks between dumpings, but I can understand the reasoning behind getting the tank fairly full to ensure that the solids are being disolved.

Please give me your opinions and tell me how it has worked for you...

Thanks again.

Faith

[Tallyrver]

During the hot months in North Florida I like to flush every trip ,unless i go the next weekend .No use carrying around a bunch of toxic stuff .

[bldrbob]

I dump even if not very full. Then refill with fresh water and dump again. Then add some water so tank is not completely dry.

[WilleyB]

Don't know what others do, but I just add more water then dump it. I wouldn't leave a small load brewing in the tanks while the RV sits in the driveway either, but then again that's just me.
Second option, if you know it's going to be a short stay, use more water when you flush and flush often.
Willey

[awarnes]

I usually dump every other trip. Unless I'm not going to be using the RV for longer than 2 weeks. JMHO

[exrench]

My black tank is about 1/4 full and by the time we take our Fall trip,the tank contents will have had six months to "mature" and will not smell any worse at that time! In the event of "cooking", (your term)the tank vent system will take care of the off-gassing effect.I do drain the hot water heater for such a layover to avoid the sulphurous odour when put back in service.The trap for the washer/dryer needs to be filled to avoid gray water tank smells in hot weather.

[jzick]

We travel continuously for 6-7 months and then winter at the Fl stick and bricks with just a few weekend trips then. On our last leg of the journey to storage we will use the motorhome facilities as normal. The unit will then be parked for several months. During that time the black and grey may be used by me while I am working on it or cleaning and get some weekend use. By spring the tanks will be 1/3 to 1/2 full. The tanks will not be emptied and sit and cook - temps can get pretty high in Fl, even in winter. Never had an odor problem. You can do whatever you are most comfortable with - if you want to dump just add more water to the tank and dump.

[David K]

I dump after each trip -- no matter how full the black tank is. After dumping the black tank and while the grey tank is dumping, I turn on the black tank washer and let it wash for about 5 minutes and then dump it again followed by about 2 minutes of more water with the valve shut after the second dump. That way the black tank is not completely dry. Also, after about every third dump of the black tank, I pour in some Calgone water softner in the black tank after the small amount of water is added. This mixture "sloushes" around while I am driving and it helps to keep the tank walls nice and slick so nothing will stick to them.

[wa8yxm]

BBFT (Back before full timing) I'd dump at the end of every trip, No matter how full.

If you feel the need for more liquid in the tank so as to get the proper "WOOSH" effect, ADD before dumping.. That's what the tank flusher is for, or hold a hose over the regular tank "Inlet" while holding it's valve open.

[Rodneykrantz]

I was told If you fill the tank up with water before you open the valve it causes a swirling effect and emptys much better

[Peddler]

Quote:

Originally Posted by David K followed by about 2 minutes of more water with the valve shut after the second dump. That way the black tank is not completely dry. .

That way makes sense to me but the sticker on the coach, as well as advise I've read on the boards, say you are never to use the tank rinse inlet without the tank valve being open.

The only problem I could think of would be pressure build up in the tank but would think the tank vent would prevent that. Anyone else use the tank wash inlet to add water back in the tank?

[96 Wideglide]

Quote:

Originally Posted by Peddler That way makes sense to me but the sticker on the coach, as well as advise I've read on the boards, say you are never to use the tank rinse inlet without the tank valve being open. The only problem I could think of would be pressure build up in the tank but would think the tank vent would prevent that. Anyone else use the tank wash inlet to add water back in the tank?

I do, and yes, mine has the same warning !

[HeapBigEngin]

Faith....there was at one time an interesting post on this forum by a gentleman who provided a very detailed discussion of a process he uses to keep his tanks clean and odor free. It involves using laundry detergent, Calgon and ocassional bleach. As the second owner of this coach, I use this process on our Revolution's tanks....and it made an incredible difference. And the process is relatively inexpensive. Re dumping, a lot of good thoughts already presented. Suggest you do a search for that article I mentioned if it is of interest to you.

[DrDaveCA]

The warning is so you do not "forget" the black tank flusher is running and walk off. If you do that you will ONLY do it once.

I flush after every trip, living in the Charlotte area it gets a bit warm and I do not want that toxic mix cooking in my coach. After I dump the black tank I close the valve (you can't get me to move with a gun ), run the flusher to fill the tank at least past the point before I dumped it the first time. Once the flush is drained I close the black tank and run the flusher again to put about 5 gallons in that tank (at the same time dumping the grey tank to wash it all down). I then throw a packet into a clean black tank until the next time we go out.

I also have a clear section in the dump hose so I can see when the black tank runs clean (if it takes an extra flush I do it). That's just 1 man's way of avoiding a "Robin Williams".