[Gleaming windows]

something like this

http://cgi.ebay.co.uk/12-VOLT-WATER-HEATER-IMMERSION-Element-solar-wind-12v-V_W0QQitemZ180296624112QQcmdZViewItemQQptZUK_Home_Garden_Hearing_Cooling_Air?hash=item29fa8427f0

I dont mean to be overly critical and maybe I have got this completely wrong, but that 12v heater aint gonna touch a 400 litre tank of water surely.

If it could heat a tank of water that size then why do we have the dogs danglies immersions in domestic tanks in our houses? Surely because you need something with some balls to heat water?

[Gleaming windows]

In fact according to the figures published on the ebay page its gonna take something like 4 days to heat a 400 litre tank buy 35 degrees using the 600W element.

[LBWCS]

if all you want is to stop your water freezing when it gets cold i cant see the problem with buying the element from ebay. Get another leisure battery and put it on for an hour before you start and keep it on for a while. Im going to try that

[Richard 01903]

Hi someone told me you could use a L 5 Shower Heater ,looks good on the web!!!!

[daz1977]

this is an arguement that can go on for years,  if it is just to stop the water freezing then them elements would be fine,  personally i would just fill up with hot water in the morning, as i fill up in the morning anyway now, 

it all depends if the water he wants is warm, or hot, depends on which way to go

something like this

http://cgi.ebay.co.uk/12-VOLT-WATER-HEATER-IMMERSION-Element-solar-wind-12v-V_W0QQitemZ180296624112QQcmdZViewItemQQptZUK_Home_Garden_Hearing_Cooling_Air?hash=item29fa8427f0

I dont mean to be overly critical and maybe I have got this completely wrong, but that 12v heater aint gonna touch a 400 litre tank of water surely.

If it could heat a tank of water that size then why do we have the dogs danglies immersions in domestic tanks in our houses? Surely because you need something with some balls to heat water?

they are that big, so that they heat a tank 20 - 30 mins, when needed

you could put an immersion tank (out of a house) in the back of your van, and rig up an immersion coil, to a plug and plug it in 30 mins before you leave in morning, that will give you hot water all day

could try an ele shower unit out of a camper van, that might work, heat the water as needed

[ccmids]

its a 500ltr tank in the back of my van.

[daz1977]

y do you want, is it just to stop it freezing or so you can use hot water on windows

[Sunshine/Cleaning]

If you plan on killing yourself then use 240v with water, just get some insurance first.
Secondly you will, unless you DI after the tank, need to get a special type of immersion as the regular ones will send the DI skyward, dont ask me why.
Anything running off 12v will need a battery the size of the van to generate enough power to raise the temp of the water.

If you go for gas heating check out the regs on carrying gas as they are quite prohibitive.

[ccmids]

has anyone ever added a water heater to the system they have, if so whats the best way for me,  would you buy one at £2000 and more or try diy .
if diy whats the best way , i've thought of heating the water buy re routing the hot water from the heater in my van which would go through a coil in the tank then heat water.
or fit 240 volt immersion to tank switch on for 1/2 hour and heat it that way.
the 12 volt immersion are no good like someone said it would take a long time to heat a 500 ltr tank.

[jonnyald]

has anyone ever added a water heater to the system they have, if so whats the best way for me,  would you buy one at £2000 and more or try diy .
if diy whats the best way , i've thought of heating the water buy re routing the hot water from the heater in my van which would go through a coil in the tank then heat water.
or fit 240 volt immersion to tank switch on for 1/2 hour and heat it that way.
the 12 volt immersion are no good like someone said it would take a long time to heat a 500 ltr tank.

that wouldnt work ,not enough heat . even if you drove the van 1ooo miles  it would have the same effect as dropping a single lighted  match into Lake Windermere

[ccmids]

if you type this in youtube       hot-backback  this bloke has done it on smaller scale.