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What is head of water?


Tennentslager

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The Morco caravan boiler (LPG with battery ignition---NO mains power on site) needs 1 bar of pressure.

Plan A was to connect to the local main but for a hundred reasons this is difficult. However 20m from site there is a public stand pipe and it is okay to connect a hose to this but never permanently.

No comments about *tapping* into this with a cheeky underground junction, that would be just plain wrong!

*If* I use a hose to fill a header tank to feed the boiler, how high would it need to be to give me 1 bar.

From what I can understand it's 10m. Plenty of big trees around but FFS that's a lot of work to have a hot shower.

 

Edited by Tennentslager
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Yep, 1 bar = 33ft in old money. I wonder if you could organise a pumped feed instead? If the one bar is simply a minimum, and the heater doesn't require a very narrow pressure range, then a pump might be the easier option.

If you are only allowed occasional connection to the stand pipe then a header tank sounds useful anyway though.

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Thanks @Temp but that's pricey and any pump needs to use what little battery power I have.

Dunno what force is in the standpipe but it fairly skooshes out lots on full whack...(hope that's not to offensive for the technically educated) so if I can get a container up a tree...I guess a hose could be used to charge it up.

But what could be lashed to a giant fir tree 10m up and what size for a couple of showers and some dishwashing of a weekend?

Edited by Tennentslager
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I fear you may have bought the "wrong" caravan heater. That's probably meant for a static 'van with mains water connection.


 

You would be better off with a touring caravan unit. They tend to be storage heaters rather than instant heaters. All then need is a cold water container and a small 12V pump.  Pump cold water in and it pushes the hot water out of the top. And the little 12V caravan pumps can manage to pump water from these to give a just about acceptable shower.

 

Chances ar you could get one cheap or even free from a rotted out old touring 'van.

 

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I'm going to presume that a caravan water heater is not going to have a tremendous output so you'll probably want to limit the flow rate in order to keep the temperature up. Does it have a kW rating?

 

I know from personal experience that you can just about shower in five litres (one of those solar bag thingies) but it's not the best experience ever! As an absolute minimum a shower at home would be using 5l/min so say 20-30l per shower as an absolute lowest figure. So you're looking at about a 100l container to give a couple of showers and a bit left over.

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In our touring 'van the "limit" is about 25 litres of water for a shower. The trick is to turn the little storage water heater up to maximum (almost scalding hot) then dilute with plenty of cold, then you can have an acceptable shower before the hot water runs out (the limit being when the cold water tank runs dry)


 

The Morco heater I am pretty sure is what we have in the static 'van and it's powerful enough to heat water instantly for a shower. They do use a lot of gas while running so tend to like the larger gas bottles.

 

Here's the sort of caravan heater I am talking about http://www.ebay.co.uk/itm/caravan-water-heater-/172511488144?hash=item282a7c6890:g:KU8AAOSwnHZYknjQ


 

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24 minutes ago, Nickfromwales said:

What water system / plumbing do you have so far? You've got a wash hand basin and kitchen sink, they plumbed in already?

Do you have attic / high up space for a coffin tank ( storage tank with fitted lid etc ). ?

Wash basin and sink are dry fitted ATM.

I've enough space above toilet for a tank but about 2m the floor. Probably 1.5m above the taps.

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2 hours ago, Nickfromwales said:

What's the crack with the upstand? Is it just a communal,'outside tap' ?

 

Yup, stand pipe in a wooden housing with a tap that has threaded end to take a hose fitting.

You can see the plastic pipe that feeds it and someone has teed off this rather obviously to blag his own water supply.

Clearly against all regs, probably the law too and pretty easy to follow the trail to him so he will get caught eventually.

At present we use 5l water bottles and fill from the tap, usually 4 at a time.

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Just an off-the-wall idea, but if you can get a decent hose to the standpipe, how about installing an accumulator to store water in the hut, under pressure? 

 

It takes up space, but could be put outside in an insulated box.  If filled via a NRV on the accumulator, via a removable pressure hose that fits the standpipe, you could have water at the same pressure as at the tap, with no pump.  Fit a pressure gauge and you have early warning that the tank is getting low and needs topping up.  You could then have ordinary plumbing in the hut if you wanted to.

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That would need sufficient pressure at the upstand. Any chance of getting a reading? Late evening is best when the local network is under less demand. 

If one person has teed off the upstand, does anyone actually care as long as it's not getting abused? If they were watering the garden all day then that's one thing, but an occasional hand wash or 5 min shower isn't going to have anyone in tears  is it? How many people share the upstand?

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I'm leaning towards a coffin tank for cold to the kitchen sink and wash hand basin. Fill this from a hose and fit an overflow in case of forgetfulness?

For the winter months I can drain this down before heading home for freeze protection...sound sensible?

The big 8 pint kettle on the stove works well just now...mix with some cold and it's perfectly comfortable.

I suppose the Hut is a holiday place and there's never a hurry to get up and out to work. Morning routine is pretty relaxed so no bother if the water takes a while to heat. If in a hurry the gas stove boils a kettle in 5 minutes. Might be best to stay low tech for now?

 

 

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