Mark, I would reconsider diesel. I have had 3 of these little diesel furnaces, An Espar currently cooking me every cold night year round in my work truck, a Planar in a van build and a Chinese knock off yet to be installed but I've played with it on the bench. I bought it for a pick up wedge camper but not sure if I will bother installing or just sell.
The reason you might want to reconsider is that space saved (by the small footprint of the unit over ANY other heater), efficiency (the diesel heaters will run all night on 12 oz. of diesel) and safety (personally I just can't get my head around a gasoline fired heater while I sleep, regardless of how well made).
Carrying a one gallon can of diesel for your heater and only needing to fill it up every 3-4 days is manageable and the heater itself takes up a fraction of the space you need for a Propex (which I am familiar with and have installed) and it's assorted plumbing, tanks, etc. Yet another consideration is price of fuel. A gallon of diesel will cost you $3. I have no idea how the equivalent propane measures up but I know it's not that cheap.
Compare these two charts and look at how little fuel these use, .15 liters per hour on medium setting for the diesel, twice that for petrol. I used to fill up my 7 liter Planar tank about once every 5 nights because these units don't run constantly, they cycle.
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