313 RLTS Gray Tanks

[Thebohs]

So I have my 313RLTS out for it's maiden voyage and I possibly have an issue. I have two grey tank valves, one in the control center and one mid way down the unit near the dump connection and two indicators on the inside control panel "Grey One" and "Grey Two".

I ran the kitchen faucet, bathroom faucet, and shower but only the "Grey One" light showed any indication of filling up. In fact it went all the way to full. I kept the water going past full thinking there was a crossover pipe which would start filling "Grey Two" once "Grey One" was full. I turned the water off when I heard the tank groaning from the weight, and "Grey Two" never came off empty.

So then I went and pulled the valve in the control center and nothing came out of the dump outlet. I then pulled the valve midway down the unit and all the water drained.

So my question is: are there two tanks and how do they work? Is there a crossover pipe? The manual doesn't really cover it.

Thanks!

 

[TucsonJim]

Since the 313 is a relatively new unit, you might have better luck asking Grand Design directly. You can copy and paste your request in the "Tech Corner" section at the bottom of the forum page, or call customer service directly at (574) 825-9679. GD monitors the Tech Corner section and responds there.

Jim

 

[Dave and Monica]

Moved to the Tech Corner as Jim suggested.

Dave

 

[Thebohs]

Question answered by GD Customer Service (JD Adams to be precise).

Grey one is for bathroom sink, kitchen sink, and shower. Grey two is for the washer/dryer prep.

Thanks again to JD and GD Customer Service! Where else can you get this kind of response from an manufacturer?

 

[Barbara & Dave]

Question answered by GD Customer Service (JD Adams to be precise).

Grey one is for bathroom sink, kitchen sink, and shower. Grey two is for the washer/dryer prep.

Thanks again to JD and GD Customer Service! Where else can you get this kind of response from an manufacturer?

That's good to know. Does anyone know if is this SOP across the GD family, across the Reflection line, or unique to the 313?

Dave

 

[Dave and Monica]

This is not the case in the Reflection 5th wheels where you have a galley tank and gray tank for the bath/shower. On our 337, the washer drain is routed to the gray tank...I think that's true for the other floor plans too. I've never seen a waste water tank dedicated to the washer hook-up.

Dave

 

[TucsonJim]

That is a very odd set up. On ours, the kitchen is one tank, all the others are the other tank. If you don't have a washing machine, you never use the other tank. Very odd.

 

[Lingerlonger]

That's good to know. Does anyone know if is this SOP across the GD family, across the Reflection line, or unique to the 313?

Dave

It is not true for my 2014 Reflection 337RLS. One Gray tank is for the galley and the second gray tank is for the bathroom sink, shower, and apparently the washer/dryer hookup. (I haven't used the washer hookup yet.)

K

 

[james quinn]

so is the 75 gallon gallon grey tank capacity split between two tanks (ie: 37/37) 'cause that would be a dumb setup ? ; Especially if one of them is dedicated solely for washer !

 

[Lingerlonger]

For my 2014 337RLS, and I believe all Reflection 5W's, the two gray tanks are separate with no flow through.
The easiest way to combine their capacity is to install a separate gate valve at the dump point and leave the two
valves for the gray tanks open. They will eventually equalize giving you the combined capacity.

See: http://www.amazon.com/Valterra-T58-...426680508&sr=1-1&keywords=rv+sewer+gate+valve


You will find a few threads here also about the individual capacity of some of the tanks not being as high as advertised because of the placement
of the vent pipes.

K

 

[james quinn]

For my 2014 337RLS, and I believe all Reflection 5W's, the two gray tanks are separate with no flow through.
The easiest way to combine their capacity is to install a separate gate valve at the dump point and leave the two
valves for the gray tanks open. They will eventually equalize giving you the combined capacity.

See: http://www.amazon.com/Valterra-T58-...426680508&sr=1-1&keywords=rv+sewer+gate+valve


You will find a few threads here also about the individual capacity of some of the tanks not being as high as advertised because of the placement
of the vent pipes.

K

Except that then u woulld be limited to dumping the grey before the black and if you aren't where you can flush then that would suck! Setup on 5th may not be bad because both tanks can be used without washer. If 313 TT has tank separately for washer then you you have a tank that you may never use and low capacity of the one you can. Poor design if that's the case.

 

[Lingerlonger]

True. But you may also be able to close the two gray valves, before draining the black and then open the grays to flush. I am not sure.

Also, I think most people would not be inclined to use the washer unless they are on FHU anyway.

In my experience, I use a lot more water from the bathroom sink and shower than any of the others. So I drain that tank every day or two.
(But I don't normally do any dry camping)

K

 

[Thebohs]

Poor design if that's the case.

I agree. When researching TTs, one of my criteria was a large grey capacity, the other was the floorplan. With 75 gallons, the 313 had more grey capacity than any other TT I was considering, except the Crossroads Hill Country 32RL, which had a similar floorplan and 80 useable gallons of grey.

Had I known that, in reality, the capacity was only 37.5 gallons, I can just about guarentee that I wouldn't have bought the 313. Don't get me wrong, I absolutely LOVE it, but still... No where in the literature does it mention the split tanks. Just a guess on my part, but I bet fewer than half of the buyers would ever install a W/D. This just makes for an odd design decision.

I must temper my semi negative comments with the fact that I love Grand Design products, their quality, and especially their customer service!

 

[Cate&Rob]

You will find a few threads here also about the individual capacity of some of the tanks not being as high as advertised because of the placement
of the vent pipes.

K

This is a bit of a long read, but the summary is that many of us have found that the grey tanks only hold about 2/3 of their stated capacity.

http://www.granddesignowners.com/forum/showthread.php/1450-Holding-tank-size?highlight=Boomer

Rob

 

[mburtsvt]

Question answered by GD Customer Service (JD Adams to be precise).

Grey one is for bathroom sink, kitchen sink, and shower. Grey two is for the washer/dryer prep.

Thanks again to JD and GD Customer Service! Where else can you get this kind of response from an manufacturer?

So the advertised grey take capacity of 75 gallons only works when you install an option that GD does not offer, (washer/dryer). Is something wrong here.

 

[GDRV Service]

This is not the case in the Reflection 5th wheels where you have a galley tank and gray tank for the bath/shower. On our 337, the washer drain is routed to the gray tank...I think that's true for the other floor plans too. I've never seen a waste water tank dedicated to the washer hook-up.

Dave

Hi Dave (@Dave and Monica),

Correct - in some applications the galley tank supports the kitchen sink only. Forward grey supports shower/lavatory sink. Not all units are washer/dryer prep.

Best regards,
~ Janice

 

[TucsonJim]

By all means, I'd put an external gate valve on and then open the two gray tank valves to equalize the two gray tanks. When it comes time to dump, close both the gray valves, and start dumping. First, the gray water that was in the discharge pipe will dump. then open the black tank valve and dump it. Finally, open the two gray valves and dump those tanks. It will give you pretty much the full capacity of both tanks while doing these steps, and you'll still be able to flush your hose with gray water as the final step.

 

[Cate&Rob]

On "equalizing" the two grey tanks . . . do we know that they are the same height and mounted at the same level ?
Judging by eye, I think the galley sink drain is a little lower than the shower drain . . . so that is where you will first know when you have reached the combined limit.

Rob

 

[james quinn]

Saw it myself yesterday at factory ... 75 gallons split between two tanks (not one tank as advertised) with a front tank exclusively for washer. Washer tank drains (pipe runs on exterior of trailer ... not insulated) to main discharge. Equalizing if it would work (I don't think it will) could subject exterior pipe to freeze in cold and restrict the equalizing and/or draining of both grey and black tanks. Poor Design.

 

[WhittleBurner]

That system is only when washer prep is ordered. Otherwise nothing is outside of insulation. Our 303 holds at least 75 gallons. When we measured it it was over 75. We attributed that as some extra going into the pipes. As stated before 1 tank is for the bathroom and the other is for the kitchen. The external gate does work because both tanks are equal in height. Doing that you do have a full 75 gallon gray tank system.