Grey water confusion

T

TheMobileWanderer

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I've just looked at a Phoenix which has two water filling points, one for fresh water and one for grey water.

So, does the shower run from the grey water tank and release back into it, presumably with some form of filtration?

That's what I thought when I first considered a MH build but moved away from that thought during my research, hence my confusion now after seeing the grey water fill.

Or is it two reservoirs (fresh and grey) rather than one tank to feed both kitchen sink and shower, perhaps to provide better balance in the load?
 
New one to me - grey water filling tank?
Closest is a separate toilet flush tank?

Can't see the point in filling up for grey and fresh?
 
Could it just be an auxillary tank fitted, I think carpmart has an extra tank for a pressure washer?
 
Well each was labelled in German but I could understand the labels to read, fresh water and grey water. The only reason I can think why they would be separate is to maintain vehicle balance. At home, the one tank feeds everything in and outside the home. I really doubt that grey water is recycled / filtered / purified within the system.
 
Just a few thoughts on your spec, take them or leave them but based on my usage in my RS ….
I would up the lithium to 400amps
8kw inverter seems overkill unless you have a reason. I have 3kw and that seems fine - maybe compromise on 4kw
Endless hot water - have you worked out what size fresh you want to have ? Make sure you get a good match. Terms of the grey tank - sometimes the grey tank is not big enough to match the fresh
Strongly suggest you go for the Omnivue 360 camera system and large monitor. - you will never regret it
Never thought of a camera for locating drop spot underneath - great idea. I will pinch that although not sure how it would remain clean if sited under the vehicle

C
 
ceejayt said:
Just a few thoughts on your spec, take them or leave them but based on my usage in my RS ….
I would up the lithium to 400amps
8kw inverter seems overkill unless you have a reason. I have 3kw and that seems fine - maybe compromise on 4kw
Endless hot water - have you worked out what size fresh you want to have ? Make sure you get a good match. Terms of the grey tank - sometimes the grey tank is not big enough to match the fresh
Strongly suggest you go for the Omnivue 360 camera system and large monitor. - you will never regret it
Never thought of a camera for locating drop spot underneath - great idea. I will pinch that although not sure how it would remain clean if sited under the vehicle

C
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Thank you.
Hoping to stay below 7.5t but if i need a C licence, that'll be another pleasurable challenge.
The 8kW muliplus may be overkill (excessive) relative to other spec but I want the system to be upgradable (more battery etc) and it's cost wasn't much more than a 5kW version.
Endless hot water: 10L mightn't be enough for my shower.
Camera system on the list and I'll consider that one.
Camera beneath; not my idea but read about it somewhere, possibly here.

David and Sally: it was two fillers, just like fuel filler caps. I'll try to find the photo and post.
 
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Here's a screenshot
1000006399.webp

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Presuming you have a grey water outlet I can only assume the inlet is to enable you to add water to the grey tank for cleaning.
 
TheMobileWanderer said:
I've just looked at a Phoenix which has two water filling points, one for fresh water and one for grey water.

So, does the shower run from the grey water tank and release back into it, presumably with some form of filtration?

That's what I thought when I first considered a MH build but moved away from that thought during my research, hence my confusion now after seeing the grey water fill.

Or is it two reservoirs (fresh and grey) rather than one tank to feed both kitchen sink and shower, perhaps to provide better balance in the load?
Click to expand...
It's possible there is a tank for drinking/showering water and another for flushing toilets. Some houses are like that with rain water collected from the roof stored in a tank for toilets. I can't see much advantage in a motorhome although I guess you could fill it with water collected from lakes or rivers.

As already suggested it is probably just a normal grey tank with a filler to flush it out.
 
Figaro said:
Puzzling 🤔 why would you not just run the taps to add clean water to the grey waste tank for cleaning ?
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Because when I want to add some water to the grey tap, to dave time I just run a hosepipe into the tank via the inspection cap. I would love a filler point like that.

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You certainly wouldn’t ever want to use grey waste for the shower.
I think some Phoenix models have the ability to use grey water to help flush out the black water tank after emptying. If so this would allow you to top up the grey water tank if needed to help flush the black waste?
 
KNWH said:
You certainly wouldn’t ever want to use grey waste for the shower.
I think some Phoenix models have the ability to use grey water to help flush out the black water tank after emptying. If so this would allow you to top up the grey water tank if needed to help flush the black waste?
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Good thinking 🤔 🙂
The advert says this amongst its blurb.

Waste water tank Flush connection via filler neck as with fresh water
Click to expand...
Advert here, for info. (I've no connection so seller or owner)
autoline24.uk

Phoenix 7900 RSLX *EuroCargo* 7,49 to.!*Vollausstattung* motorhome

Phoenix 7900 RSLX *EuroCargo* 7,49 to.!*Vollausstattung* motorhome sale advertisement from Germany ➤ Motor caravan ✓ Price: €266,370 ✓ Mileage: 700 km ✓ GN39768 ✓ Autoline United Kingdom
autoline24.uk autoline24.uk
 
Nice van, but cheaped out on some things, only 115 lt water tank, 330w of solar, certainly want more than that.
 
ceejayt said:
Just a few thoughts on your spec, take them or leave them but based on my usage in my RS ….
I would up the lithium to 400amps
8kw inverter seems overkill unless you have a reason. I have 3kw and that seems fine - maybe compromise on 4kw
Endless hot water - have you worked out what size fresh you want to have ? Make sure you get a good match. Terms of the grey tank - sometimes the grey tank is not big enough to match the fresh
Strongly suggest you go for the Omnivue 360 camera system and large monitor. - you will never regret it
Never thought of a camera for locating drop spot underneath - great idea. I will pinch that although not sure how it would remain clean if sited under the vehicle

C
Click to expand...
If you have the Omnivue system they will plot the waste and fill points on the roof for you. They did it retrospectively on ours.
 
Wh05apk said:
Nice van, but cheaped out on some things, only 115 lt water tank, 330w of solar, certainly want more than that.
Click to expand...
115litres is tiny on a van like that. You need 300 minimum

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TheMobileWanderer said:
Here's a screenshot
View attachment 1032944
Click to expand...

I was thinking more that descriptions are more for the source and quality of the water, rather than its use.

So, along the lines of Frischwasser is to describe water that is cleared as 'Potable' for drinking, and the Grauwasser is from recognisable sources but is not deemed sufficiently pure for drinking, which could be used for clothes washing, floor and other cleaning etc., even for topping up engine cooling systems or windscreen washer. These latter uses may be more aimed at those who really camp off-grid, where water sources are rare.
 
Payload 919kg once you stick in full water, clothes, grub, the grey is full, add on any more accessories, bikes, fill the garage, extra solar etc etc for a van that size there won’t be sufficient remaining at 7.49kg total weight.
 
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nicholsong said:
I was thinking more that descriptions are more for the source and quality of the water, rather than its use.

So, along the lines of Frischwasser is to describe water that is cleared as 'Potable' for drinking, and the Grauwasser is from recognisable sources but is not deemed sufficiently pure for drinking, which could be used for clothes washing, floor and other cleaning etc., even for topping up engine cooling systems or windscreen washer. These latter uses may be more aimed at those who really camp off-grid, where water sources are rare.
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I wouldn't think its that Geoff, my money would be on it simply being access to the grey tank to wash it out.

EDIT If you go to Phoenix web site https://www.phoenix-reisemobile.de/ausstattung/sonderausstattung/sonderausstattung-midi it says,

Gas/Water:​

  • Waste water tank flush connection by means of filling neck as with fresh water
 
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CazPaul said:
Payload 919kg once you stick in full water, clothes, grub, the grey is full, add on any more accessories, bikes, fill the garage, extra solar etc etc for a van that size there won’t be sufficient remaining at 7.49kg total weight.
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I don't think it's bad Paul but it's the best you are going to get on a truck chassis.

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funflair said:
I don't think it's bad Paul but it's the best you are going to get on a truck chassis.
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Well it says then in the write up Zuladung 540kg so thats confusing to one of the photos with the plate weights on?
Zuladung is payload in German.

I think a weighbridge would be in order before proceeding.
Personally if it was me I’d be wanting that Motorhome on a MAN chassis at 8600kg and take the test.
 
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ceejayt said:
I would up the lithium to 400amps
Click to expand...

The proposed system is a 48V system where 300Ah is equivalent to 1200Ah at 12V; you don’t think that’s enough and advocate 1600Ah?

Ian
 
CazPaul said:
Well it says then in the write up Zuladung 540kg so thats confusing to one of the photos with the plate weights on?
Zuladung is payload in German.

I think a weighbridge would be in order before proceeding.
Personally if it was me I’d be wanting that Motorhome in a MAN chassis at 8600kg and take the test.
Click to expand...
I was surprised that a 7500kg Eurocargo was claiming quite so much to be fair, we have about the same payload on a Daily with all the options added and water gas and driver, it's plenty for us (y)
 
bigtwin said:
The proposed system is a 48V system where 300Ah is equivalent to 1200Ah at 12V; you don’t think that’s enough and advocate 1600Ah?

Ian
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I did not realise that. Interesting although I am not techie enough to understand how that would work
 
ceejayt said:
Won’t work for black tank drop outlet though
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Yes, they plotted that on for me too. I sent them a picture of the side of the MH with a bucket marking where the outlet was positioned. They placed logos on the roof view of the MH in the Camos system to enable me to line up with the drains. I am laid up having just had my knee replaced, but I can send you a picture once I am up and about again. Finally, just an endorsement of how good Trailer Vision's customer service is. They have been excellent to deal with.

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