What are the dimensions of your lean to? How many cords are stacked in it? I’m heating a 40X60 pole building, my old 2 story farm house and the domestic hot water for both with a Central Boiler 6048. I use @ 13 cords a year burning 27/7 365.
32 x 8, stacked 7.5 feet high, so I reckon around 15 cords I heat a 5000 sf log home with radiant floor heat and domestic hot water but only burn 10/1-4/30 approximately. and burn whatever wood I get for free, so species varies (I avoid only pine). So in an average winter I’d burn two of those wagons to start in shoulder season, about 1.6 cords and about 13 from lean to, 14.6 total for year