when galley tank is full, what happens?

[FL-mph21]

my galley tank always shows 33% full, even after emptying

what will happen when it's full?
will water start coming up the kitchen sink drain, or worse...?

and of course,
what are some things i can try, to clean the sensors?

thank you
marc

[Mr. Dan]

Do a search for sensors and you'll find pages of threads about sensors that lie. My galley sensors pretty much say my tank is 2/3s full even when empty unless the tank is open at home and has completely dried out. An overfull galley tank will show water in the galley (kitchen) sink. I've never seen my galley overflow exit any other place.

[formerFR]

We've seen the lowest drain, the shower, stop draining when the gray tank is full, but sometimes we've even seen the kitchen sink stop draining as well. That's usually our 'indicator' that we're full, as I don't rely on my sensors, probably haven't since the day we first started.
I always look at it this way: if there not standing water in the kitchen sink, or the shower, we 'aint full yet!

now.... the next question is certainly going to be about when the 'other' tank is full, but that's an easy one as well. If you can see standing water below the toilet outlet when you open the foot pedal, then you're close!

[phillyg]

Sensors lie; it's probably empty. The water will just start backing up the sink drains. No problem unless its unattended and overflows, or the dump site is a long way off.

[JohnD10]

When the shower of kitchen sink starts draining slowly...it is time to dump the gray tank!

[beechjet16mf]

On our Flagstaff 27RLWS, when the grey water tank is full, it backs up in the shower. Our sensors read 2/3 full all the time, so, I have found out about how many days go by before we are full. That's when we empty.

[Swampy]

You can use the GEO method for the Grey Tank. Fill and dump your grey tank a few times with water. add a cup of Calgon water softener and a cup of the cheapest liquid laundry detergent, and about 5 gallons of water. (If you do this before the trip home or on the way to the CG, it should jostle around and clean the tank while in transit.) Use your tank as you normally would and your sensors should clean themselves of the grease build-up and start working like new.

Good Camping! Swampy

[Grapehound]

It's funny, I have had our Rockwood 8282 for nearly three years and I don't think I've looked at my tank gauges more than three or four times. They have never been accurate in any of my three trailers. I can empty the tank and check the gauges right away and they'll say I am still 3/4 full. I think the manufacturers add them to impress you with all lights and the technology, but they have the accuracy of a Quija board.

I'll have to try the Calgon and soap thing.

[mecd]

The more content the greater stress on the supports for the tank and the potential to separate the tank from the fill pipe to that tank. They are not cemented apparently. In our CC, we had an odor that the dealer determined was caused by just that. After putting things back together un-cemented the odor disappeared. This 40-year RV veteran and senior RV tech suggested that when hooked to sewer service always leave the grey tank(s) (we have two) open. That is okay as we have an internal flush on the black tank that keeps the sewer drain pipe clean. I have also talked to other RV'ers who have had many years of experience suggesting the same thing. If you do not have a black flush system merely close the grey valve(s) a day or so before emptying the black tank and all is okay.

We no longer have a problem with the gauge readings on any of the tanks and will continue this practice. Downside is a CG without sewer service at the site or boon-docking.

[Lloydg]

The best tank sensor is my wife when she yells at me that the sink is backing up. That's when it time for me to jump into action and dump the tank!!

[jimmoore13]

You say "galley" grey water tank. I'll assume you have a second tank for the bathroom sink and shower. That's not terribly important, but it makes a difference.

With an isolated galley grey water tank, it is theoretically possible for a full tank to eventually prevent your sink from draining. It won't "back-up" into the sink per se, but water won't go down. Another alternative is that if you have a drain vent through the side of the rig (as I have), depending on the location of that vent, it's possible grey water will begin draining out that side vent. That's unlikely, because the vent should be higher than the bottom of the sink, but one never knows. In my case a FULL kitchen sink is actually slightly higher than the outside drain vent, and it would dump some water before the water in the sink got below the level of the vent.
(The photo depicts the drain vent for my shower, but I have the same kind of device outside my kitchen sink on the side-wall of the camper. I also have a black-tank vent that goes through the roof...a more conventional setup.)

If you have the common "instavent style" vent tucked under your sink, it, too, might leak a bit of water if the sink is really full. They are not designed to we water tight, and by design they must be slightly below the underside of the counter. So water in a super full sink will be slightly higher than the top of the instavent.

In a unified grey water system, the low point is the shower drain. In ours, this is the case, and the shower pan will begin to fill with grey water, because the sink is significantly higher than the shower pan. This is actually a "back-up" with grey water in the tank rising into the shower pan. It's nasty, but it's easy to deal with. I drain the grey tank into a bucket and dispose of the grey water, then I use a product like Clorox Cleanup to clean and sanitize the shower pan. We have only made that mistake twice in 5 seasons with our current rig.

The shower does have a trap, but gravity being what it is, grey water from the kitchen sink has about a 3 feet gravitational advantage as it pushes water into the grey tank. The shower pan often forms the top of the top of the grey tank (as is the case with our rig), so that slightly pressurized water easily pushes up through the trap and into the shower.

My wife and I are profligate water users. My rig carries 26 gallons and I tote 28 gallons in jugs in my truck. Our 12-gallon black tank is quickly overwhelmed. I find that I'm dumping about 10 gallons of grey water a day. I mention this because it's possible to get a crude estimate of how much you use and then roughly estimate how full your tank is by the number of days you've been filling it. Use a 5 gallon bucket to measure after a "routine" trip. Rather than dumping grey water out the sewer hose, dump it into the bucket and use that as a measure. If you go out for 4 days and fill the bucket 8 times after that trip, you'll have a good idea that you're dumping 40 gallons of grey water...10 gallons a day. You already know how big your grey tank is, and you can plan accordingly.

Grey water can be drained into a couple 5 gallon buckets (3 1/2 to 4 gallons at a time to enable easy, dry carrying) and toted to the nearest restroom or pit toilet. If you're boondocking, water the trees with it. Sink water is similar to the kinds of grey water used to irrigate crops and water golf courses. This comment may spark some "flaming," but the soaps (surfactants) in dishwater are actually beneficial soil amendments, and the tiny amounts of particulate (usually food-grade) waste are harmless. If you're wise, you wipe you dirty dishes clean of food waste and fats into the trash before washing, so very little in the way of solids should be going down your drain...after all, unless you have a pretty fancy rig, you don't have a disposal, and if you're boondocking, you may not have the power to run it. If you're in bear country, dump far enough from your rig to ensure any curious creatures won't be invited into your campsite. We boondock exclusively - in bear country - and our grey water has never attracted an uninvited guest. If they did come they'd surely be after the smell of the grill, dog bowls or other far more attractive smells than dishwater. (Because we are in a pop-up (a glorified tent), we take lots of precautions to not attract bears...including moving ALL food into our locked tow vehicle overnight.)

There are more elegant solutions for transferring grey (and black) water, but I think they are overkill for grey water. A 5 gallon bucket (or two) is all you need to deal with excess grey water.

[myxkp]

Originally Posted by FL-mph21

my galley tank always shows 33% full, even after emptying

what will happen when it's full?
will water start coming up the kitchen sink drain, or worse...?

and of course,
what are some things i can try, to clean the sensors?

thank you
marc

My wildwood 27rkss has a separate galley tank - I usually have to empty it before my other two. It just backs up into the kit. sink. Wiping dishes with a damp paper towel has cut down on the number of times I have to empty the galley tank.

[itat]

We use the Geo Method plus a bacterial product called RV Digest-It for both tanks. The flusher for the black tank can usually get the senors cleaned and reporting empty when they should. We don’t have a flusher for the grey tank so I pour in some Super Clean degreaser before a trip if the sensors don’t read empty when they should.

You can conserve some volume in your grey / galley tank by using dish pans for dishwashing water and dumping the dirty water down the toilet. Wiping off your dishes and pots before washing them is a great idea to minimize the amount of food and grease getting in your tanks.

[Villagerjjm]

It may come up through the shower drain.... lowest point for grey water.

[moshe1436]

Before leaving the dump station I use the Geo method in the black water tank. I put in 8 oz laundry detergent, 8 oz of Calgon water softener, one bottle of Aqua-Chem and about 2 gallons of water in the black water tank after dumping.

In the toilet bowl, I put about 4 oz of an inexpensive vegetable oil to preserve the seal and keep it sealed when not in use (it does not evaporate much at all).

We also do what a lot of people do in foreign countries where sewage treatment is not very efficient by NOT putting any paper in the toilet. We use a small flip top can next to the toilet and empty it when "it's time." This had helped a great deal to let the black water tank drain and it keeps the tank clean and free of debris.

Some extra work at the dump station but totally worth it!

[1984fireball]

Mine worked for maybe 2 weeks. After that they are less reliable than the weatherman. I leave my 2 grey's open and the day I want to dump the black I close them. My toilet actually starts to "burp" when it is getting close to full. If your drain pipes under the sink are not perfect then the full galley backing up can leak out of the pea traps. Water inside is never good.
They sell aftermarket sensors that look good and have goo reviews. I would replace mine but it would be a pain to get to them so I leave the grey open...

[bedubya]

The best camper mod I have ever made:
I don't know why it's sideways. On my PC, it's not.

[bedubya]

2nd attempt

I give up. I quarter turned the first photo to the right.

[JohnD10]

Originally Posted by bedubya

2nd attempt
Attachment 191244
I give up. I quarter turned the first photo to the right.

It's because you shot it on a cell phone vertically.

Don't ask me why...but lots of cell phone photos will do this...no matter what you do with them on the phone or in Photoshop!

Always shoot photos horizontally (after all, most TV's and computer screens are horizontally widescreen anywayz) and they will post correctly.

[Teetime]

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