Post by hiddengarden on Jan 13, 2013 18:04:15 GMT -8
I just fnished builidng a RMH to burn pellets It is gravity fed and seems to burn with a low roar. The flames barey enters the riser by about 2 - 3 inches At one point it roared like a bear and the flame was about 18/ to 24 inches up the riser adn it was full and bright yellow. NOTE THERe IS NO BELL onit yet.
My question is can someone check my dimensions for improvement. MY goal I think is to get the ROAR and full flame.
The design is simlar to the Begelow farm pellet burner exept I used an 8 inch square riser.
Dimensions
air inlet all brick in the gorund width is 7 inches
height is about10
length is 4 bricks long or 32 at the third brick the height is reduced to 2 1/2 inches by 7 wide. this enters a veritcle chamber that is about 7 x7 wide adn rises up to the grid that holds the pellets at the entrance of the burn tunnel. think o fit as a capitol L laying on its back short end up ___|
Burn tunnel is 7 inches wide and 5 inches tall adn 14 inches long. The 14 inches bring me to the back of the riser.
shape looks like
\ \ | |
\ \ | ______| |
\ \ fire >>> |
_________ | \ __________|
| air >>> | |
|_________________|
.riser base is three course of brick and then an 8 x 8 stainless steel duct that is 48 inches high. It is surrouded by a 12 x 12 pipe with perlite in between.
I then attached an uninsulated pipe 8 x8 to the internal riser total hgight about 8 feet
Over the grate where the pellets burn I made a retrictor plate to close in much of the air fromthe top 1/2 inch gap. The plate is bent in the shape of the letter C to narrow the air gap on the top of the pellets on the burn plate.
The pellets are fed (temporaily) using a 3 inch round pipe. I plan on making a wider feed tube more in the 4 1/2 - 5 inch range
During the burn part of the grate collapsed into the ash pit (air inlet area) as I fed pellets the stove began to roar LOUD and the flame filled the risers for the first 2 feet. Prior to that there was a medium roar and the flames went about 2 - 3 inches into the riser.
the top of the riser was 750 F
Question\ suggestions? on any modifications on sizes?
The risers maybe to big? 8x8 versus 7x7 ?
I am thinking of putting ceramic tile in the burn tunnel. Idea is it may reflect more heat back into the burn area?
Also the entire burn tunnel and base of riser were only one red brick thick. top of burn tunnel bricks got warm not HOT base of riser bricks did not??
There is no P channel, though there is a slit to allow air to enter over top of pellets.
I have considered putting a secondary air pipe along bottom of burn tunnel with air exiting from slits at the end of pipe just before the riser.
Thanks
for eveyones input
Dave
My question is can someone check my dimensions for improvement. MY goal I think is to get the ROAR and full flame.
The design is simlar to the Begelow farm pellet burner exept I used an 8 inch square riser.
Dimensions
air inlet all brick in the gorund width is 7 inches
height is about10
length is 4 bricks long or 32 at the third brick the height is reduced to 2 1/2 inches by 7 wide. this enters a veritcle chamber that is about 7 x7 wide adn rises up to the grid that holds the pellets at the entrance of the burn tunnel. think o fit as a capitol L laying on its back short end up ___|
Burn tunnel is 7 inches wide and 5 inches tall adn 14 inches long. The 14 inches bring me to the back of the riser.
shape looks like
\ \ | |
\ \ | ______| |
\ \ fire >>> |
_________ | \ __________|
| air >>> | |
|_________________|
.riser base is three course of brick and then an 8 x 8 stainless steel duct that is 48 inches high. It is surrouded by a 12 x 12 pipe with perlite in between.
I then attached an uninsulated pipe 8 x8 to the internal riser total hgight about 8 feet
Over the grate where the pellets burn I made a retrictor plate to close in much of the air fromthe top 1/2 inch gap. The plate is bent in the shape of the letter C to narrow the air gap on the top of the pellets on the burn plate.
The pellets are fed (temporaily) using a 3 inch round pipe. I plan on making a wider feed tube more in the 4 1/2 - 5 inch range
During the burn part of the grate collapsed into the ash pit (air inlet area) as I fed pellets the stove began to roar LOUD and the flame filled the risers for the first 2 feet. Prior to that there was a medium roar and the flames went about 2 - 3 inches into the riser.
the top of the riser was 750 F
Question\ suggestions? on any modifications on sizes?
The risers maybe to big? 8x8 versus 7x7 ?
I am thinking of putting ceramic tile in the burn tunnel. Idea is it may reflect more heat back into the burn area?
Also the entire burn tunnel and base of riser were only one red brick thick. top of burn tunnel bricks got warm not HOT base of riser bricks did not??
There is no P channel, though there is a slit to allow air to enter over top of pellets.
I have considered putting a secondary air pipe along bottom of burn tunnel with air exiting from slits at the end of pipe just before the riser.
Thanks
for eveyones input
Dave