Gray Water Tank in an LK/LN2

[VerMonsterRV]

Hey guys, the habitat build is getting closer and after I finish up the interior refurb I will move on to the smaller details with the subframe. I had originally planned on putting a gray water tank inside so it would not freeze but have started to think about putting it outside between the chassis rails. It would give me more storage space inside and I could put a 12v heater on the tank for the times when we are out at below freezing temps in places that require a gray water tank. What are you guys doing and what do you think about this idea?

 

[DiploStrat]

This interests me as well. My previous camper, a Tiger, had an external grey tank and it never froze. The valve froze, but not the tank. I would think that for all but the very coldest weather a hot shower and perhaps a shot of anti-freeze might be all you need.

New camper has an internal grey tank, mounted high behind the dinette. The only problem with this is the need for a sump pump to lift shower and sink water. And the drain valve, mounted externally, can still freeze.

 

[Ullie]

We've mounted the grey water tank inside in the double floor. We can acces the drain valve from outside by opening a door that gives acces to the basement as we call it. (double floor)
We go with the camper on skiing trips and we've already had temperatures down to -29°C. Never had any problem with the water. If your tank is outside, in that conditions you must have heating on the tank and that takes power of your batteries, wo already have less power because of the cold and solar panels give less because of the short days.

I'm for mounting inside.

 

[LostInTheWorld]

I originally wanted to mount our gray water tank inside under our bed area, but for a lot of reasons, we decided to mount it outside just forward of the driver side rear tire. It will be nice to have it lower to keep the center of gravity low and have the shower drain into it nicely. I think we will add a heater, but that will probably be a future addition. The tank is also directly above the muffler in our case, so that will help a bit when we are on the move.

Michael

 

[Joe917]

Our gray is outside and has frozen. We now keep the valve open in sub zero temps with a 5 gal pail under the drain in camp grounds.

 

[nathane]

I'm planning on running a heating coil through an external tank from the engine coolant circuit. Switchable.

 

[grizzlyj]

Hi. Why not drop a section of the camper insulated floor within the chassis rails, create a kind of sump from insulated materials the same as the camper, then get a grey tank made to fit whatever size and shape you can get to fit?
Positioned close to the pivot between subframe and chassis there won't be much movement between the two.
It will be the coldest part of the inside, but I doubt it would need heating? You could even run part of a hydronic heater system through it too but too much heat and you'll be brewing some sort of slime monster

 

[Joe917]

Hi. Why not drop a section of the camper insulated floor within the chassis rails, create a kind of sump from insulated materials the same as the camper, then get a grey tank made to fit whatever size and shape you can get to fit?
Positioned close to the pivot between subframe and chassis there won't be much movement between the two.
It will be the coldest part of the inside, but I doubt it would need heating? You could even run part of a hydronic heater system through it too but too much heat and you'll be brewing some sort of slime monster

Probably the best option if you are building from scratch. A freeze proof or heated valve is required.
How much time spent in sub zero is the big question. If it is only a few weeks a year the open drain bucket set up is fool proof and easy.

 

[Jostt]

Big question....It was on my plan at the begining to fit it inside , but There is not enought room on my camper, At the end I think like Joe, how many time you expend on this condición for the extra job, I Will add a valvle ,

 

[VerMonsterRV]

I think Joe's solution sounds like a good one and will likely go that way. Unfortunately when I designed the subframe I put a cross piece right where the tank would be great. Hindsight being 20/20 if I would have put it a foot further back it would be perfect. I guess when we build the next one we will make this change . I will also check out the heating option now as it is likely easier to install now if not too expensive.

 

[Sitec]

Hi Jonturgeon. What toilet are you planning on using? If you go with a 'composting' type like the Natures Head or similar, then the only grey water you are collecting is from the shower and kitchen sink. This can then be collected with a smaller tank with a drain off hose at the bottom (only collecting when required to by law). Fit the tank on the opposite side to the living access door then when you are out in the open country away from camp sites etc it can just be drained into a small pre dug hole fed by the drain off hose, as it does not contain any 'nasty' stuff... This then means:- A) You use/waste little to no water in your toilet, B) You never have to handle the slurry associated with flushing toilets or cassettes, C) You are not using huge quantities of valuable water for flushing toilets, D) You can get away with a smaller (stop gap) grey water tank which (as Joe suggested) can more often than not sit with the drain tap open..

Just my thoughts on the matter. Cheers.

 

[Neil]

Our grey tank is outside between the chassis rails. Like Joe if its cold enough to freeze we just leave the tap open an either let it drain onto the floor or into a bucket depending where we are.

Been below minus 20 no problems.


Neil

 

[VerMonsterRV]

To follow up, at this point we are seriously considering a composting head (yup, I know all the issues around them and I do agree, and will likely have 2 tanks). So the gray tank will be for the shower, bathroom sink and galley sink. And if we go crazy a washing machine (which since we are both turning 50 soon and have never owned our own it seems about time ).

 

[Joe917]

100% on the washing machine. It makes life so much easier.

 

[jebers53]

Our 2013 Tiger has external gray and black tanks with Tank Heaters so don’t freeze. When we have needed to dump in sub freeze temps we have warmed the valve with a hair dryer (my wife would never leave home without it!). Sans hair dryer, there are valve heaters as well if you wanted to mount the tanks exposed.???