2 Gray Water Tanks?

[NEO noob]

Just coming off of a great 1st trip in our FR Vibe Xtreme Lite 227RLS. Camped at an electric hook up site (no water / sewer). We were using our potable water tank, gray tanks, and black tank.
On our last day, about 10 mins after taking a shower, gray water started to back up in the shower (when wife was using the kitchen sink/drain).

Control panel showed:
Gray Tank #1: Full
Gray Tank #2: 1/2

TT has 3 gray water sources:
Shower
Kitchen Sink
Bathroom Sink

I assume that the shower and the kitchen sink share one tank and that the bathroom sink uses the other gray tank.
Unfortunately, FR manuals are very generic and are of no real help.
Does anyone have an idea why the two “hi volume” water sources (shower & dbl. kitchen sink) drain into one gray tank and the smaller volume source (small bathroom sink) drains into the other gray water tank?
Seems that it would make more sense to have the small bathroom sink and shower plumbed together to the same gray tank vs. two of the three highest drain water sources draining into the same gray tank.
Any thoughts or suggestions?
Much appreciated!

[spock123]

You could install a valve on your sewer line and then when you have that problem again open up both grey water tanks and let them equalize.

[ttocsmi]

I had a similar email exchange with someone at FR last fall, and learned that it depends on your floorplan. But the dealers don't tell you how it's plumbed (probably because they don't know) when you buy the unit. Search around, there are a number of threads on this same topic.

I asked for drawings/schematics/etc for my unit - nope! I verified my layout by running a hose through each inside drain and observing which tank filled and which dump valve each was connected to.

On my 243BHS, the kitchen is on grey #1, the bathroom sink is on grey #2 (??!!??), and the the outside sink, toilet, & shower are on the black tank.

[ependydad]

Originally Posted by ttocsmi

But the dealers don't tell you how it's plumbed (probably because they don't know) when you buy the unit. Search around, there are a number of threads on this same topic.

I asked for drawings/schematics/etc for my unit - nope! I verified my layout by running a hose through each inside drain and observing which tank filled and which dump valve each was connected to.

I found that my dealer told me how it SHOULD be plumbed, not necessarily how it was. I had to figure it out by running + dumping water like ttoscmi indicated.

[NEO noob]

Thanks for the information.
I’ll try running the different water sources to see which tank they drain into.
Kind of frustrating - the lack of resources available from the manufacturer or dealer.
Again, I appreciate the response!

[Oaklevel]

We do not have your make but our last 3 campers had the shower and bathroom sink on one grey tank and the kitchen sink was on the other.

At least they are not like the older campers that had only one tank for everything.

[RFGTLG]

We have a Minilite 2506S with two gray tanks, one for the kitchen sink, and the other for bathroom and outside kitchen. There are two drains as well. If you have two drains, consider after they are full, drain one and check the sensors.

[Gm Mike]

We have 2 grey water tanks as well. Bathroom sink and shower on 1 and galley on 2. Two separate dumps as well. Tank 1 will back up into shower if full and the bathroom sink is used. My greys are 35 gallons each and after awhile, you get the hang of it as to how much you can use or have to conserve in the case of no hook ups.

[DouglasReid]

Originally Posted by NEO noob

Just coming off of a great 1st trip in our FR Vibe Xtreme Lite 227RLS. Camped at an electric hook up site (no water / sewer). We were using our potable water tank, gray tanks, and black tank.
On our last day, about 10 mins after taking a shower, gray water started to back up in the shower (when wife was using the kitchen sink/drain).

Control panel showed:
Gray Tank #1: Full
Gray Tank #2: 1/2

TT has 3 gray water sources:
Shower
Kitchen Sink
Bathroom Sink

I assume that the shower and the kitchen sink share one tank and that the bathroom sink uses the other gray tank.
Unfortunately, FR manuals are very generic and are of no real help.
Does anyone have an idea why the two “hi volume” water sources (shower & dbl. kitchen sink) drain into one gray tank and the smaller volume source (small bathroom sink) drains into the other gray water tank?
Seems that it would make more sense to have the small bathroom sink and shower plumbed together to the same gray tank vs. two of the three highest drain water sources draining into the same gray tank.
Any thoughts or suggestions?
Much appreciated!

We too have 2 grey tanks.

The shower and bathroom sink are on one. (they are literally 3' from one another)

The kitchen sink, which is in a different portion of the camper is the only thing that drains into the other grey tank

Don't think volume of water, think location of the drain.

Some campgrounds like you to drain grey water onto plants near camping site, many FORBID it.

For those that do you can purchase a drain cap for your sewer hookup that has a male hose connection with a screw on cap to allow you to hook up a water hose to drain onto the plants. (DO NOT use any hose that you use to get fresh water into the camper and DO NOT do this unless the campground permits it)

For those that permit it you can use the hose to keep your most used tank from backing up into the shower.

[CedarCreekWoody]

On mine there is a valve between the two grey tanks. Open to combine the tanks, close to keep separate.

[FredK]

You can obtain Septic Dye Test Tablets for under $20 to use so you can find out which drains go to which grey water tanks. www.ToolExperts.com


On my 33' 5er, I just opened up my valves, one at a time and used Hot water to see where it went. I also found that the indicater lights are not always that accurate. Probably 75% accurate!

[DouglasReid]

Originally Posted by CedarCreekWoody

On mine there is a valve between the two grey tanks. Open to combine the tanks, close to keep separate.

That would be very nice. We do not have such a valve.

[rockfordroo]

Originally Posted by NEO noob

Just coming off of a great 1st trip in our FR Vibe Xtreme Lite 227RLS. Camped at an electric hook up site (no water / sewer). We were using our potable water tank, gray tanks, and black tank.
On our last day, about 10 mins after taking a shower, gray water started to back up in the shower (when wife was using the kitchen sink/drain).

Control panel showed:
Gray Tank #1: Full
Gray Tank #2: 1/2

TT has 3 gray water sources:
Shower
Kitchen Sink
Bathroom Sink

I assume that the shower and the kitchen sink share one tank and that the bathroom sink uses the other gray tank.
Unfortunately, FR manuals are very generic and are of no real help.
Does anyone have an idea why the two “hi volume” water sources (shower & dbl. kitchen sink) drain into one gray tank and the smaller volume source (small bathroom sink) drains into the other gray water tank?
Seems that it would make more sense to have the small bathroom sink and shower plumbed together to the same gray tank vs. two of the three highest drain water sources draining into the same gray tank.
Any thoughts or suggestions?
Much appreciated!

To answer your question, it's just like real estate: Location, location, location. Looking at your floor plan, I'm guessing the black tank is directly below the toilet. That means they need a grey tank forward of the black for the kitchen sink and one aft of the black for the bathroom sink. Then they have to make a decision on which one to plumb the shower to. They will plumb it to whichever one is easiest for them. ( Based on your floor plan, I would have guessed the shower goes to the forward tank even if you hadn't already said so.) Unfortunately, they don't always consider the volume of water each input may contribute to the tank it's connected to. Sometimes they do, and use a larger tank for the one with more input, but again, there may not be room. The tanks have to be small enough to fit between the crossmembers of the frame.

As mentioned by others, depending on how the tank drains are routed, you MAY be able to plumb the two gray drains together and create a "single" tank. Usually the biggest obstacle is having an axle in the way, but I don't think that's an issue for you, as it looks like the tanks would all be forward of the axle.