Looking for mobile home rocket stove ideas

I'm not looking for a hyper efficient system. Just something that can help take the edge off the colder nights. The park I live in doesn't allow wood stoves but pellet stoves are fine. I want to be as safe and smart about it as possible. I intend on buying a 30 to 55g sized barrel. I have a few questions tho concerning the build. I currently have a pellet stove stove pipe system going through the wall. 3in pipe I believe. Does the exhaust pipe out have to be the same size as the pipe going in? The barrel I intend to stack brick around the inside walls. Does the exhaust going out of the stove need to be higher then the feed tube? I kinda want to build a 3in system for now and over the summer work on making a larger and more efficient system. Right now I dont need pretty, just functional. Any thoughts and ideas and plans are welcome. I eventually want to build my own heat riser with local clay as well. Sorry, 500 questions come to mind. I just want a design that works and go from there.

Hi Jason!   Warm welcome to the rocket scientist corner of the internet.
For starters, an excellent resource for answering a lot of your questions can be found in the Rocket Mass Heater Builders Guide by Erica and Ernie Wisner. Loaded with pictures, tips and advice from those that have built a lot of stoves and share what they have learned.

Jason LaPort wrote:Does the exhaust pipe out have to be the same size as the pipe going in?

Yes. To keep it simple, all cross sectional area from feed to exhaust needs to be the same except for the manifold area which is the transition from the barrel to the mass.

Does the exhaust going out of the stove need to be higher then the feed tube?

Usually it ends up being lower but then it goes (relatively) straight up and generally a few feet above the roof peak.

I kinda want to build a 3in system for now and over the summer work on making a larger and more efficient system.

It has been suggested many times and by many people that the smaller you go in size (than a 6" system), the harder it is to make the stove run properly and cleanly.

Poke around the Rocket Mass Heater forum and look at some of the builds that others have done. Lots and lots of information that can keep you busy for a while.
Good luck with your build and do post pictures when you begin so we can see what you have and help you out easier.

I'm not real educated on rocket mass heaters
but the mass part of the name means there is alot of weight involved.

How would that work with something like a mobile home?

With being a mobile home I'm a little less concerned about thermal mass. I do intend on adding some brick to the barrel to hold some heat. Otherwise I would have posted this question in the mass heater forums instead.

Right now the exit pipe is only 2ft from the floor. If I decided to use all stove pipe for the burn tunnel how long should I expect the pipe to last before it needs to be replaced?

If you have your stove pipe insulated, I would say it would last about a month at proper rocket stove temperatures before it burnt right through if not sooner. Just a guess though.