Rocket mass heater materials

I am looking into building a rocket stove. 30 gallon drums seem to be more difficult to come by so I am looking into 55 Gallon. What would make a good size pipe for the inside of the combustion chamber?

So I am thinking of building a rocket heater room off of the house where the propane tank is. Installing the feed chamber on the outside of the room and the combustion chamber/mass on the inside. The idea here is that the built room with get hot, like sauna hot, and I can install a fan on the house to blow the hot air through the existing fire place to warm the house. Any thoughts?

Paul Abbott wrote:So I am thinking of building a rocket heater room off of the house where the propane tank is. Installing the feed chamber on the outside of the room and the combustion chamber/mass on the inside. The idea here is that the built room with get hot, like sauna hot, and I can install a fan on the house to blow the hot air through the existing fire place to warm the house. Any thoughts?

I don't know how well that would work. The most certain thing is that you loose the best part of the heating system. The mass. The best thing about the RMH is the mass. Having the mass as close to the centre of your living area as possible will work the best and give the safest most gentle heat. As soon as we go to heating air and using it as a transfer medium we want to start with warm air. A RMH does not warm air as well as other wood heaters. For most uses that is a plus. The surface of a RMH is kept at less than 200F normally closer to 100F so it can be sat on without burning either a person or the dust in the air. A RMH warms people by radiation and conduction, not by keeping the air warm (convection). Air has very little mass and so works best as a heat transfer medium when heated as much as possible. The inside of a furnace would be in the 700 to 1000F range (just a guess... anyone know? I do know that it is hot enough to burn dust though), but by the time the air gets to the vent I can hold my hand in front without harm.... such are the losses of a forced air system. I think if you built things that way... you would find the people in the "sauna" most of the time... as a side note... in days of old, people did tend to spend a lot of time in the sauna, even sleeping there.

Wow, it says this was my 800th post...

You make some good points. Perhaps a similar setup with no mass. I like the idea of forcing the air down causing a rapid release of the heat. Maybe I should just focus on that aspect of it.

Paul Abbott wrote:You make some good points. Perhaps a similar setup with no mass. I like the idea of forcing the air down causing a rapid release of the heat. Maybe I should just focus on that aspect of it.

It is certainly possible to build a rocket radiator. I would use a smaller CSA rocket like 6 inch not 8 so that I would not make too much heat to use as I produce it. In fact, without a mass bench, 4inch might work just fine. Check the thread below for an example:

https://permies.com/t/10367/alternative-energy/Cyclone-rocket