• Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education skip experiences global resources cider press projects digital market permies.com private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Anne Miller
  • Nicole Alderman
  • r ranson
  • Pearl Sutton
  • Mike Haasl
  • paul wheaton
  • Joylynn Hardesty
  • Dave Burton
  • Joseph Lofthouse
master gardeners:
  • jordan barton
  • Greg Martin
  • Carla Burke
  • Ash Jackson
  • Kate Downham

bench temps

Posts: 137
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
what is the hiest temp acheved by the bench materiel? i seen one video where it was stated to be, 140 after 12 hours down time! is that an average scenario? anyone lay thermometer on theirs at full heat?

thanks ron
Posts: 4154
Location: Northern New York Zone4-5 the OUTER 'RONDACs percip 36''
hugelkultur fungi books wofati solar woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Ronald Bush : Assuming a good clean and efficient burn we have flue gas temps starting out at ~1000~dF and we finnish with an Exhaust gas temp at the base of our
final vertical chimney around 150dF. The densest material will hold the most heat, that and the Total amount of the volume of theThermal mass will determine the Final
Number of B.T.U.s stored within the thermal mass, at first we get a lot of heat energy transferred with out much increase in temps, The densest material within the Mass
will 'Transfer' heat energy from the Hottest side to the cold or cooler side at about 1 inch an hr !

With the Rocket Mass Heater RMH sized correctly to the heating season needs, 3-5 hours of tending to -results in 20-25 hrs worth of heat energy stored within the Mass
The deeper down into the RMH we place the exhaust pipe the lower the final temperature at the Bench Surface will be !

Many successful RMH users use throw rugs, padded quilts, or other bedding type materials on top of their bench ( Futons come to mind ) for padding and for some
additional heat retention !

This is a build up to saying that it happens that you can suddenly Note that the freshly ironed laundry smell from your bedding is starting to have a scorched linen smell
it drives my wife crazy that she smells it before me, I get the third degree about' am I planning on starting a fire today?' leading up to the bench being cleared off till
after I have allowed the fire in the RMH to go out.

This is as close as I have ever come to monitoring the temperature of the RMH Thermal bench, Hope this helps ! For the Craft! Big AL

Posts: 3757
Location: latitude 47 N.W. montana zone 6A
cat pig rocket stoves
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi ronald; In my greenhouse I have bench temps at full burn as follows. My horizontal transition area is a small bell, I read temps of 200 + there , the start of my mass routinely gets to 130-140 , the far end of the mass gets to around 100 or so. This is a greenhouse so depending on outside temps after 12 hours, i have apx 120-150 at the bell and 90-100 at the start of the mass and 75-80 at the far end. If this were in an insulated house I would expect higher temps after only 12 hrs.
Rocket Mass Heater Manual
will be released to subscribers in: soon!
    Bookmark Topic Watch Topic
  • New Topic