Rocket Mass Heater - Making Heat!

We had a successful firing of the rocket mass heater!  We kept a fire going for over six hours Sunday evening, and didn't fill the house with smoke a single time.  Whew... What. A. Relief.  Not that I was that worried that we built a giant mud pile in the house for no reason.  We weren't ready to give up on the rocket mass heater, but we had such a smoky experience the last time we fired it that we were hesitant to try it again until we understood what was going wrong.  But this time, we got it so hot that the dragon had steam coming from his nostrils - and the house was warm enough for a t-shirt, on a night when the temperature dropped the single digits, even.  I kept trying to take a picture of the dragon's steam, but it doesn't show up very well.  Maybe if you use your imagination you can see the cloud of steam coming from it's nose and hear the gentle roar of the fire.  Imagine warmth on your face and body while you stand near the hot barrel.  

It wasn't until our potter friend, Joe, explained the Venturi effect to Brandon over lunch recently, that we formulated a plan of action.  Joe suggested that the thin metal pipe that exits the house and carries the slightly warm exhaust up and away, was so thin that the cool from outside was invading our pipe and we were loosing pressure.  Joe explained that when a kiln looses the Venturi effect, it's like someone inside the kiln blows out the fire.  That's exactly what it was like in our rocket mass heater!  Joe suggested a gas pilot light in the exhaust pipe, like they use in kilns.  We did some research on pilot lights, and Brandon even took apart an old gas stove that came with the house, but we could never get comfortable with putting gas into our exhaust system.  Instead, we wrapped the exterior pipe with hot water heater insulation and a put a heat lamp inside the cap of of the clean out.  It worked beautifully.  I have hopes that once the cob bench is dry and warm that we won't need the heat lamp, especially now that the pipe is insulated.  

But for now, I'm happy to have a fire, even if the heat lamp wasn't something we planned for.  The cob bench is still drying, and the surface is cracking like we predicted.  I spent a few minutes playing in the mud and patching the cracks.  Once it's bone dry, we hope to treat the surface with something less crumbly.  

It's so cold outside!  There's nothing like frozen mud and sprinkles of snow to make me appreciate a burning log in the dining room. 

The baby chicks in the brooder have a heat lamp of their own, and an enclosed brooder box tucked into the barn.  But the big chickens and the guineas don't get any heat.  Since this was the first single digit temperatures of the winter, Brandon and I stapled a tarp to the chicken coop, so they would be protected from the wind on three sides.  

The guineas had their first day of freedom on the farm yesterday.  They started out their adventure with the chickens, but it wasn't long before I saw them exploring the yard on their own.  Thankfully they didn't take off for parts unknown.  At dusk, I was happy to see them near the chicken coop trying to find their way back inside.  It took them over an hour to finally figure out how to go in the door.  They walked in circles around the coop, went under it, jumped on the side, tried flying through the walls, and finally figured out the door.  I tried no to watch since it was making me crazy.  Just go in!

My toes are warm!

Brandon seemed to be enjoying himself as he split firewood in the back yard.  Puck thought it was great fun too.  I have some thoughts about a back rest for the rocket mass heater, and some cushions.  In the mean time, a cardboard box and some afghans come in handy.  So far, only the area near the barrel is warm to the touch.  

Just ten minutes on top of the barrel, and a plate of nachos and cheese with a foil cover becomes crispy, crunchy, cheesy "rocket nachos".  

Happy dragons have steamy noses.