Well, i have so enjoyed reading and watching all and everyone's examples of this tried and true fundamentally sound heater.
It has bothered me since almost the beginning of why the exhaust hasn't been put to work so that ALL elements are used to their maximum ability.
More than one narrator has touted that the exhaust is basically STEAM?
Would it not be a functional effort to use this STEAM up inside of a greenhouse / indoor greenspace ? Maybe run cotton strings or fishing lines ( so to keep mold from growing), run these lines from some upper gathering zone ( not the engineer-here), and by use of these "lines" flow the reconstituted moisture down into a collection tank which might direct feed some indoor plants?
I don't know what might be accomplished with this application. I am just beginning a design for a patio mass heater. Perhaps move into the garage. Medical challenges are foremost though, So, time is an issue on good days.
But, since i have been planting since i was a mere 18 months old and WE RECYCLE, i do enjoy ALL examples on this fine site and others.
If you get the exhaust cold enough where you can start collecting steam and the heavy steam/CO2 is flowing down vs up to the sky.
Then you are going to have reduce draft and a colder, smokier RMH.
Even in a properly functioning RMH, the exhaust will contain some carbon monoxide, VOC, and other nasties, that your family/pets should not be exposed to.
Even "safe" carbon dioxide will knock you out and kill you if the levels get high enough.