Roy Johnson : Do you have Ianto Evans' great book 'Rocket Mass
Heaters' , if not go to www.rocketstoves.com - a download (as many copies as you want) $15.00u.s. or paperback $18.00u.s. . there is no other book with as much information in it. It is the book most commonly used at Rocket stove mass heater work shops !
With recent upgrades to the insulation inside the Heat Riser, the pyrolyzed
wood gases are truly consumed, and the oft stated goal of Hot exhaust and just water vapor and and Carbon Dioxide is possible and easily maintained.
How ever there are longevity issues with the new insulation and time is needed to determine if it will downgrade
enough to allow production of carbon monoxide .
Even with the presence of a CO detector I would not feel safe in an indoor environment where my rocket stove was discharging!
In an Enclosed greenhouse, with the Rocket stove discharging internally, and sealed up by frost or freezing rain the Rocket stove would slowly consume all the oxygen in the air, its last combustion products as it choked to death would certainly contain carbon monoxide, I for one would not want to take that chance.
A Rocket Stove just a few years old with cracks, internal plumbing partially plugged with wood ashes*, or just less than perfectly DRY Wood,** or the wind shifted to a new direction Can and Will smoke, and produce wood vinegar, methanol, tars and creosote, not a good diet for tender young seedling plants ! A reminder that when the plants are not actively making sugars they are then using those sugars for growth and survival, it is then that they open their stomas to take in Oxygen and would be bathed in toxins !
There are also issues related to the artificially high moisture content of the air and soil in a greenhouse, a certain # of air exchanges are needed to keep molds,mildews, and damps at bay not just for the plants also for the longevity of the wooden parts of the greenhouse !
What are the length and widths of your tank, Regular stove pipe can be found in 5 foot lengths, this would leave the sealing to water tightness to the area of the holes in most tank walls. With just a little pre-cooling you could even use galvanized stove pipe to promote longevity, or go deep with the heavy gage black
wood stove grade stove pipe - though I have not seen it in 5 foot lengths locally !
With the the water tank already at a maximum temperature of 80 F ***, you would have no trouble getting down to the point where you would be able to capture and use the latent heat of vaporization, and you would have the ability to trap most of your water vapor and sample exhaust gases so you would know exactly how clean your Rocket stove was exhausting ( don't throw away your Carbon Monoxide detector ) carbonated soda anyone !?!
This reads more negative than I intended, and is not intentional, I hope at the least I have given you something to think about ! Pyro-maticly yours Allen L.
* Frequent cleanings are important to keep the pipes open and check for the presence of any condensed water vapors. Trapped water, and the lye in wood ashes are a bad combination that i leave to your imagination !
** Wood stored inside the G.H. during the growing season will draw enough moisture out of the air to be problematic for good fires and nearly useless for starting Rocket Stove Fires
*** Though the tank should not be sealed it certainly should be covered !