this is a rough guide of how i have fitted a secondhand 24volt eberspacher night heater from a wagon to my 2005 fiat doblo mpv, i hope you find this guide useful but please note that my vehicle has undergone several previous internal modifications to the rear load area as i use it for work, so your vehicle will have a slightly different load area but you will get the idea!,

Eberspacher heaters are available in several models and heat outputs and voltages, i obtained a nice quality secondhand 24 volt D2 (2200Kw max ) airtronic diesel fired nightheater with 7 day programmable timer from the delights of ebay for a very reasonable figure, you will find these retail at about 1200.00 new but secondhand serviced units are available very cheaply on auction sites, i chose a 24volt version as they dont attract much attention from people and therefore they are substantially cheaper compared to the 12 volt item, for those of you who are not familiar these heaters are fitted to a variety of vehicles mostly wagon cabs, ambulances, and narrowboats etc etc