This time of year I don’t usually get too muddy, but I brought some mud into my office last month so I could have a better and more efficient source of heat — finally! This little “heater hat” effectively turned my little iron box stove into a mini-masonry heater — with an oven! (note the wooden door on the right, just above the iron stove door). The wood that used to over-heat me, briefly, in the morning, now keeps me comfortably warm all day, and into the next morning (depending on how long I fire it and how cold it is). And, unlike most iron stoves, it doesn’t generate that fierce, drying attack-heat that people try to moderate, either by burning wet wood, or by damping down their fire so it heats minimally and smokes prodigiously.
The stove was an old cast-off that now provides clean heat from a clean fire. The surface temperatures of the heater portion are much lower than hot iron and (except for the tile, which gets hotter), very huggable. In addition, I lined the firebox with brick, which keeps the metal surfaces cooler and safer, but increases internal combustion temperatures for a cleaner burn. Once hot (which takes up to about 10 minutes), no visible smoke comes out of the chimney. I typically burn it for less than an hour and have heat all day (I live in western Oregon, so it’s not that cold). In my under-insulated cabin, the “hat” usually holds heat until the next morning. Oven temps vary depending on what and how I’m burning, but we’ve had several breakfasts out of it…).
The ornamental work illustrates the flame path: exhaust gases vent out the back of the stove (to the L. in the photo), then go up and around the oven (to the R.), then back up (on the L.), then in a zig-zag pattern through the narrower section on top, from L to R, then back again, and up. The core is built from a couple dozen or so firebrick — mostly splits — and some old bits and pieces of ceramic flue tile, all covered in mud.