That's right as Tim120 said. I am a "qualified" Alde "technician" as I have been on the engineers training course. I used to be a Gas Safe registered "engineer". It's all just lego with pipes, gas and water / coolant. Personally I wouldn't want the Alde sysem in my camper, too much extra weight with all the coolant and radiators, on top of the servicing and maintenance costs. Think of your home central heating system: all the bits that go wrong with it are there in the Alde system. To me it is just another showroom bling thing, quite unnecessary when there are existing perfectly good heating systems, although the current combi boilers are not as good as the old Truma / Carver gas convectors. My camper has a diesel heater which is not as good as the original Carver convector heater and if I go anywhere with an electric supply I just plug in a 500W greenhouse heater. I use the diesel heater if there is no electric, but of course you use it if they are charging for it.