Post 9
I thought I would write a review of my experience with the rocket mass heater in the Red Cabin. Before staying here I had never used a rocket mass heater, and had done minimal research, so this will be a newbie perspective.
The first couple nights were hard. I kept getting smoke back, I had the wood at an angle, and I only had one or two pieces in there at a time, because otherwise it would go out. I have since learned to prime the chamber until I can feel the air sucking into the feed tube. Also, it has worked best for me if there are several pieces of wood in feed tube, but maintaining decent amount of space between the pieces so that the fire can flow. Thinking about
flow while working with this heater has been helpful
Another thing that was not immediately obvious to me was how the RMH feeds itself, sorta. The wood is only really burning at the bottom of the chamber so as it burns through, gravity breaks the wood, and unburnt wood gets into fire. Sometimes though if the fire is going out, the sticks need a little poke to break and feed more fresh wood into the flames.
The heater does a decent job of heating up the cabin if it is running hot for at least 90 mins. That mass at the red cabin has a wooden bench, which has never felt warm to the touch after lighting and running the fire, which kinda makes sense since wood doesn't hold heat well. I have also felt the pebbles in the mass which get up to about room temperature. In the morning it can be colder than my preference, but it is still warmer in the cabin than outside.
I have lit some of the other RMHs here that have wider feed tubes, and they are easier to use. I haven't gotten as much smoking with those and you can load larger pieces. Since the red cabin has the mini RMH we are splitting our wood very narrow, and have to get up to feed it relatively frequently. Some days, it lights really easily, other days, I try for what feels like an hour, only to be in a cold space with a smoke headache. Overall, the RMH is really cool, and it is very efficient with the wood, but the mini is hard to use, and I think there could be better material for the bench so it would actually warm.
The following video is my attempt to capture the heater, the flames did not come out very distinctly, but hopfully gives and idea. If you all would be interested I can make a more extensive video about this heater