Does anyone know how big the combustion fan is in a corn stove?

Obviously it is dependent on the size of the unit, but I am trying to
determine how big(CFM) the fan is.

I am considering building one myself, but am unsure as to what sort of
airflow they are creating. I would guess it is 40-50 cfm, but would
not be surprised to learn it is much higher.

Any ideas?

thanks

JW

jw wrote:

Does anyone know how big the combustion fan is in a corn stove?

Obviously it is dependent on the size of the unit, but I am trying to
determine how big(CFM) the fan is.

I am considering building one myself, but am unsure as to what sort of
airflow they are creating. I would guess it is 40-50 cfm, but would
not be surprised to learn it is much higher.

Any ideas?

thanks

JW

Diameter and pitch should do it
for volume

"jw" wrote in message
ups.com...
Does anyone know how big the combustion fan is in a corn stove?

Obviously it is dependent on the size of the unit, but I am trying to
determine how big(CFM) the fan is.

I am considering building one myself, but am unsure as to what sort of
airflow they are creating. I would guess it is 40-50 cfm, but would
not be surprised to learn it is much higher.

Any ideas?

thanks

JW



I've been playing around with the same thing. I know they are using a blower
to speed combustion, but I'm having trouble making it work.

I made a little burn box (2" diameter pipe, air supplied to the bottom) then
I applied air to from my air compressor. I adjusted the air flow with a ball
valve. Then, I attempted to light the corn with a propane torch. Regardless
of the volume of air, I couldn't get it to light. Then, I took a 6" pipe and
started a wood fire in it. Applied corn to the existing fire, and it burnt
quite nicely.

Let me know what you come up with.

???

diameter, pitch of what? Wouldn't speed be relative as well?

Diameter would be easy enough to measure, but how do you determine
pitch of a fan blade?

JW

Get a flat surface under the fan... ie piece of sheet metal etc. Measure the
angle of the blades from this flat surface = pitch

Another idea is to go to a shop that sells them and ask for the information
as if installing.


"jw" wrote in message
oups.com...
???

diameter, pitch of what? Wouldn't speed be relative as well?

Diameter would be easy enough to measure, but how do you determine
pitch of a fan blade?

JW

Greg Krynen wrote:
Get a flat surface under the fan... ie piece of sheet metal etc. Measure the
angle of the blades from this flat surface = pitch

This assumes that it is an axial fan. Also that it is possible to get
to this without dissassembling the unit.

What I have seen are generally squirrel cage fans.

JW

Another idea is to go to a shop that sells them and ask for the information
as if installing.


"jw" wrote in message
oups.com...
???

diameter, pitch of what? Wouldn't speed be relative as well?

Diameter would be easy enough to measure, but how do you determine
pitch of a fan blade?

JW

On 2 Nov 2005 14:21:15 -0800, "jw" wrote:

Does anyone know how big the combustion fan is in a corn stove?

Obviously it is dependent on the size of the unit, but I am trying to
determine how big(CFM) the fan is.

I am considering building one myself, but am unsure as to what sort of
airflow they are creating. I would guess it is 40-50 cfm, but would
not be surprised to learn it is much higher.

Any ideas?

thanks

JW

The combustion air flue blower even in a 100,000 BTU/hr furnace is not
very big. I'd guess that 50 cfm would be plenty for a corn stove,
probably would need to be throttled some.

Sounds good. I was planning on throttling it via a PWM and/or some
other driver circuitry. Damper doors would also work, but would be
harder to control automatically.

Eventually I plan to develop a controller for this so that it is
relatively automatic in regulating itself.

Does anyone have any idea where to source a small(2") auger to be used
for the feed auger?

JW

jw wrote:
Sounds good. I was planning on throttling it via a PWM and/or some
other driver circuitry. Damper doors would also work, but would be
harder to control automatically.

Eventually I plan to develop a controller for this so that it is
relatively automatic in regulating itself.

Does anyone have any idea where to source a small(2") auger to be used
for the feed auger?

JW


Look in the garden stuff section of a big-box store (like Homely
Despot). They sell small augers for planting seeds, intended to be
drill-powered. Cheap, even.

--
Fred R
________________
Drop TROU to email.

On 3 Nov 2005 10:01:12 -0800, "jw" wrote:

Sounds good. I was planning on throttling it via a PWM and/or some
other driver circuitry. Damper doors would also work, but would be
harder to control automatically.

Eventually I plan to develop a controller for this so that it is
relatively automatic in regulating itself.

Does anyone have any idea where to source a small(2") auger to be used
for the feed auger?

Cannibalize a pellet stove? For that matter, anyone ever try burnin'
corn in a pellet stove? It's already got everything you'd need.

Snarl

On Thu, 03 Nov 2005 20:58:18 GMT, Fred R "spam
wrote:

jw wrote:
Sounds good. I was planning on throttling it via a PWM and/or some
other driver circuitry. Damper doors would also work, but would be
harder to control automatically.

Eventually I plan to develop a controller for this so that it is
relatively automatic in regulating itself.

Does anyone have any idea where to source a small(2") auger to be used
for the feed auger?

JW


Look in the garden stuff section of a big-box store (like Homely
Despot). They sell small augers for planting seeds, intended to be
drill-powered. Cheap, even.
4" is quite common in soils testing equipment.
Gerry :-)}
London, Canada

If I had a pellet stove to cannibalize this would all be a relatively
moot point.

Around here they are not available new(6-8 mo waiting list). Used they
are just as scarce(or expensive).

JW

My guess is that the blower is much smaller than 40 cfm. W.W. Grainger
sells a high efficentcy gas furnace that outputs 94,000 btu/ hour that
has a 2 inch diameter flue.

Dan

On 4 Nov 2005 07:34:07 -0800, "jw" wrote:

If I had a pellet stove to cannibalize this would all be a relatively
moot point.

Around here they are not available new(6-8 mo waiting list). Used they
are just as scarce(or expensive).

Where are you located?

Out here in th' PNW there's tons of 'em, cheap, if one looks around a
bit. There was one in Craigslist that sold for $50 a couple weeks
back. I've seen 'em free in there as well.

It took a good friend of mine 4 months to give one away. It worked
perfectly. Th' guy who took it removed th' auger and other bits to
build a Traeger style smoker bar-b-que.

Snarl

SE MN.

JW

On 2 Nov 2005 14:21:15 -0800, "jw"
wrote:

Does anyone know how big the combustion fan is in a corn stove?

Obviously it is dependent on the size of the unit, but I am trying to
determine how big(CFM) the fan is.

I am considering building one myself, but am unsure as to what sort of
airflow they are creating. I would guess it is 40-50 cfm, but would
not be surprised to learn it is much higher.

Any ideas?

thanks

Hi JW,

There are quite a few manuals available in pdf form that you
can download. This one is interesting, but I didn't see the
CFM value listed for the combustion fan. Lots of good
general info though:

http://www.eventempinc.com/stcroix/d...rd_service.pdf

Take a look at this google search:

http://www.google.com/search?num=25&... s&btnG=Search

I looked through a few manuals, but I didn't stubble across
any CFM values. Most of them seem to use variable speed
fans/controls for what it is worth...

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Does anyone know how big the combustion fan is in a corn stove?

Obviously it is dependent on the size of the unit, but I am trying to
determine how big(CFM) the fan is.

I am considering building one myself, but am unsure as to what sort of
airflow they are creating. I would guess it is 40-50 cfm, but would
not be surprised to learn it is much higher.

Any ideas?

thanks

JW

I can't give you a good answer, however, my son is currently
in the process of replacing the fan/motor in his pellet stove.
The fan is a disk of approximately 6" diameter, with radial vanes on
it, however, the vanes are only about 1/2 to 3/4 "wide" with a little
lip on the outside edge to kind of catch and hold the air that it
throws. There must be about 14 or 16 vanes. The motor is marked at
3100 rpm. However, there *is* a damper of sorts to control the amount
of air that flows. The fan in on the "output" side of the fire, and
draws air into the stove through about a 1-1/2" tube, then up through
the fire, then into the fan chamber and finally blows the exhaust out
the vent pipe. I believe it is set up this way to keep a negative
pressure on the door gasket, etc. The damper is on the input side to
the firebox and can throttle down the amount of air needed to make the
fire burn well. Hope this helps.
Ken.