Easy way to start a cold RMH without smoking back

I have learned a lot about RMH on PERMIES.COM, built a couple of them myself and presently using an 16 cm system (yes, we live in a metric system here)  at my 300+ years old, stone country house, which I visit 3-4 times a month.

After the four years of operating my RMH, I still get amazed how efficient it is. I also love the smokeless chimney, which does not need the services of a chimney-sweep anymore!  

I have built brick and concrete bell-type heat storage mass. When starting the fire in a cold house with 5 deg C (41 deg F) inside, it takes over 2 hours before the exhaust pipe gets above the ambient room temperature, while the fire is burning at full blast! Btw, in the four years of operating my RMH, I have never experienced the exhaust pipe getting over 40 deg C (104 F).

Initially, I have experimented with various ways to preheat the chimney in order to overcome the cold plug and get the draft going. It was too much hassle for me, so I have installed an electric duct-fan in the chimney system, utilizing the airbrush principle, Now I just flip a switch and have an excellent draft from the very beginning. Very convenient, especially for someone, who needs several cold RMH starts every month.

Recently, I have discovered another easy way to have a sufficient draft in a cold RMH. I have installed an electric duct-fan to facilitate ventilation in the house by blowing fresh outside air in. This creates a positive pressure inside. (Basically the opposite way what the kitchen or bathroom fans do - sucking the stale air out of the house, while creating a negative pressure, messing up the chimney draft.)

I hope my experience will inspire fellow RMH users, especially in a cabin type of environment, where they need to start a cold RMH often.

Kare Macko

Nice additions.

I do not have a RMH type stove but often wondered if adding the controls from a pellet stove would aid in giving it more control that people are looking for?

They seem so simple to tear apart and then use the augers and blowers to really control the fire. Basically a PLC controlled RMH. I also think using the consistent sized fuel that pellets is, would help really make RMH work well for so many people. Instead of gathering or obtaining firewood, they could just get bags of pellets, but the higher burn temps would better use an already great home heating fuel source.

It seems like you are almost there with your additions. Good for you.

Pellet stoves are a different kind of animal. My friend had used one for three seasons in his very small house. He had some problems with the automatic controls and after the price of pellets went up, he switched to a simple wood burning stove. He has an orchard, which provides plenty of wood from pruning the trees. Now, after seeing my RMH, he wants to build one in his new house.  Simplicity and efficiency are the main advantages of Rocket Mass Heaters.