Well bit the bullet and fitted a derv heater to the van whoooo what a difference , the heat is amazing the only dislike is the ticking from the pump i put it in a box with foam but you can still here it am looking for a different one if i can find one, took me a week as i had to make the wiring loom longer I'm using the tank that came with the unit but i will be feeding it till the van tank will post some photos when i get the chance it cost £85 i think its money well spent ,I was looking a a unit that you can heat your water form it